diff options
Diffstat (limited to 'src/compiler/scala/tools/nsc/backend')
65 files changed, 7596 insertions, 17316 deletions
diff --git a/src/compiler/scala/tools/nsc/backend/JavaPlatform.scala b/src/compiler/scala/tools/nsc/backend/JavaPlatform.scala index 6bd123c51f..dc63b335cc 100644 --- a/src/compiler/scala/tools/nsc/backend/JavaPlatform.scala +++ b/src/compiler/scala/tools/nsc/backend/JavaPlatform.scala @@ -7,11 +7,9 @@ package scala.tools.nsc package backend import io.AbstractFile -import scala.tools.nsc.classpath.FlatClassPath -import scala.tools.nsc.settings.ClassPathRepresentationType -import scala.tools.nsc.util.{ ClassPath, DeltaClassPath, MergedClassPath } -import scala.tools.util.FlatClassPathResolver +import scala.tools.nsc.classpath.AggregateClassPath import scala.tools.util.PathResolver +import scala.tools.nsc.util.ClassPath trait JavaPlatform extends Platform { val global: Global @@ -19,34 +17,25 @@ trait JavaPlatform extends Platform { import global._ import definitions._ - private[nsc] var currentClassPath: Option[MergedClassPath[AbstractFile]] = None - - def classPath: ClassPath[AbstractFile] = { - assert(settings.YclasspathImpl.value == ClassPathRepresentationType.Recursive, - "To use recursive classpath representation you must enable it with -YclasspathImpl:recursive compiler option.") + private[nsc] var currentClassPath: Option[ClassPath] = None + private[nsc] def classPath: ClassPath = { if (currentClassPath.isEmpty) currentClassPath = Some(new PathResolver(settings).result) currentClassPath.get } - private[nsc] lazy val flatClassPath: FlatClassPath = { - assert(settings.YclasspathImpl.value == ClassPathRepresentationType.Flat, - "To use flat classpath representation you must enable it with -YclasspathImpl:flat compiler option.") - - new FlatClassPathResolver(settings).result - } - /** Update classpath with a substituted subentry */ - def updateClassPath(subst: Map[ClassPath[AbstractFile], ClassPath[AbstractFile]]) = - currentClassPath = Some(new DeltaClassPath(currentClassPath.get, subst)) + def updateClassPath(subst: Map[ClassPath, ClassPath]): Unit = global.classPath match { + case AggregateClassPath(entries) => + currentClassPath = Some(AggregateClassPath(entries map (e => subst.getOrElse(e, e)))) - private def classEmitPhase = - if (settings.isBCodeActive) genBCode - else genASM + case cp: ClassPath => + currentClassPath = Some(subst.getOrElse(cp, cp)) + } def platformPhases = List( - flatten, // get rid of inner classes - classEmitPhase // generate .class files + flatten, // get rid of inner classes + genBCode // generate .class files ) lazy val externalEquals = getDecl(BoxesRunTimeClass, nme.equals_) diff --git a/src/compiler/scala/tools/nsc/backend/Platform.scala b/src/compiler/scala/tools/nsc/backend/Platform.scala index c3bc213be1..e464768bb3 100644 --- a/src/compiler/scala/tools/nsc/backend/Platform.scala +++ b/src/compiler/scala/tools/nsc/backend/Platform.scala @@ -6,9 +6,8 @@ package scala.tools.nsc package backend -import util.ClassPath import io.AbstractFile -import scala.tools.nsc.classpath.FlatClassPath +import scala.tools.nsc.util.ClassPath /** The platform dependent pieces of Global. */ @@ -16,14 +15,11 @@ trait Platform { val symbolTable: symtab.SymbolTable import symbolTable._ - /** The old, recursive implementation of compiler classpath. */ - def classPath: ClassPath[AbstractFile] - /** The new implementation of compiler classpath. */ - private[nsc] def flatClassPath: FlatClassPath + private[nsc] def classPath: ClassPath /** Update classpath with a substitution that maps entries to entries */ - def updateClassPath(subst: Map[ClassPath[AbstractFile], ClassPath[AbstractFile]]) + def updateClassPath(subst: Map[ClassPath, ClassPath]) /** Any platform-specific phases. */ def platformPhases: List[SubComponent] diff --git a/src/compiler/scala/tools/nsc/backend/ScalaPrimitives.scala b/src/compiler/scala/tools/nsc/backend/ScalaPrimitives.scala index b8ddb65de9..c18f220d95 100644 --- a/src/compiler/scala/tools/nsc/backend/ScalaPrimitives.scala +++ b/src/compiler/scala/tools/nsc/backend/ScalaPrimitives.scala @@ -7,7 +7,7 @@ package scala package tools.nsc package backend -import scala.collection.{ mutable, immutable } +import scala.collection.mutable /** Scala primitive operations are represented as methods in `Any` and * `AnyVal` subclasses. Here we demultiplex them by providing a mapping @@ -31,7 +31,6 @@ abstract class ScalaPrimitives { import global._ import definitions._ - import global.icodes._ // Arithmetic unary operations final val POS = 1 // +x @@ -62,8 +61,8 @@ abstract class ScalaPrimitives { final val NE = 43 // x != y final val LT = 44 // x < y final val LE = 45 // x <= y - final val GE = 46 // x > y - final val GT = 47 // x >= y + final val GT = 46 // x > y + final val GE = 47 // x >= y // Boolean unary operations final val ZNOT = 50 // !x @@ -447,9 +446,10 @@ abstract class ScalaPrimitives { inform(s"Unknown primitive method $cls.$method") else alts foreach (s => addPrimitive(s, - s.info.paramTypes match { - case tp :: _ if code == ADD && tp =:= StringTpe => CONCAT - case _ => code + if (code != ADD) code + else exitingTyper(s.info).paramTypes match { + case tp :: _ if tp =:= StringTpe => CONCAT + case _ => code } ) ) @@ -457,18 +457,6 @@ abstract class ScalaPrimitives { def isCoercion(code: Int): Boolean = (code >= B2B) && (code <= D2D) - final val typeOfArrayOp: Map[Int, TypeKind] = Map( - (List(ZARRAY_LENGTH, ZARRAY_GET, ZARRAY_SET) map (_ -> BOOL)) ++ - (List(BARRAY_LENGTH, BARRAY_GET, BARRAY_SET) map (_ -> BYTE)) ++ - (List(SARRAY_LENGTH, SARRAY_GET, SARRAY_SET) map (_ -> SHORT)) ++ - (List(CARRAY_LENGTH, CARRAY_GET, CARRAY_SET) map (_ -> CHAR)) ++ - (List(IARRAY_LENGTH, IARRAY_GET, IARRAY_SET) map (_ -> INT)) ++ - (List(LARRAY_LENGTH, LARRAY_GET, LARRAY_SET) map (_ -> LONG)) ++ - (List(FARRAY_LENGTH, FARRAY_GET, FARRAY_SET) map (_ -> FLOAT)) ++ - (List(DARRAY_LENGTH, DARRAY_GET, DARRAY_SET) map (_ -> DOUBLE)) ++ - (List(OARRAY_LENGTH, OARRAY_GET, OARRAY_SET) map (_ -> REFERENCE(AnyRefClass))) : _* - ) - /** Check whether the given operation code is an array operation. */ def isArrayOp(code: Int): Boolean = isArrayNew(code) | isArrayLength(code) | isArrayGet(code) | isArraySet(code) @@ -535,24 +523,11 @@ abstract class ScalaPrimitives { case _ => false } - /** If code is a coercion primitive, the result type */ - def generatedKind(code: Int): TypeKind = code match { - case B2B | C2B | S2B | I2B | L2B | F2B | D2B => BYTE - case B2C | C2C | S2C | I2C | L2C | F2C | D2C => CHAR - case B2S | C2S | S2S | I2S | L2S | F2S | D2S => SHORT - case B2I | C2I | S2I | I2I | L2I | F2I | D2I => INT - case B2L | C2L | S2L | I2L | L2L | F2L | D2L => LONG - case B2F | C2F | S2F | I2F | L2F | F2F | D2F => FLOAT - case B2D | C2D | S2D | I2D | L2D | F2D | D2D => DOUBLE - } - def isPrimitive(sym: Symbol): Boolean = primitives contains sym /** Return the code for the given symbol. */ - def getPrimitive(sym: Symbol): Int = { - assert(isPrimitive(sym), "Unknown primitive " + sym) - primitives(sym) - } + def getPrimitive(sym: Symbol): Int = + primitives.getOrElse(sym, throw new AssertionError(s"Unknown primitive $sym")) /** * Return the primitive code of the given operation. If the @@ -565,6 +540,7 @@ abstract class ScalaPrimitives { */ def getPrimitive(fun: Symbol, tpe: Type): Int = { import definitions._ + import genBCode.bTypes._ val code = getPrimitive(fun) def elementType = enteringTyper { @@ -577,7 +553,7 @@ abstract class ScalaPrimitives { code match { case APPLY => - toTypeKind(elementType) match { + typeToBType(elementType) match { case BOOL => ZARRAY_GET case BYTE => BARRAY_GET case SHORT => SARRAY_GET @@ -586,13 +562,13 @@ abstract class ScalaPrimitives { case LONG => LARRAY_GET case FLOAT => FARRAY_GET case DOUBLE => DARRAY_GET - case REFERENCE(_) | ARRAY(_) => OARRAY_GET + case _: ClassBType | _: ArrayBType => OARRAY_GET case _ => abort("Unexpected array element type: " + elementType) } case UPDATE => - toTypeKind(elementType) match { + typeToBType(elementType) match { case BOOL => ZARRAY_SET case BYTE => BARRAY_SET case SHORT => SARRAY_SET @@ -601,13 +577,13 @@ abstract class ScalaPrimitives { case LONG => LARRAY_SET case FLOAT => FARRAY_SET case DOUBLE => DARRAY_SET - case REFERENCE(_) | ARRAY(_) => OARRAY_SET + case _: ClassBType | _: ArrayBType => OARRAY_SET case _ => abort("Unexpected array element type: " + elementType) } case LENGTH => - toTypeKind(elementType) match { + typeToBType(elementType) match { case BOOL => ZARRAY_LENGTH case BYTE => BARRAY_LENGTH case SHORT => SARRAY_LENGTH @@ -616,7 +592,7 @@ abstract class ScalaPrimitives { case LONG => LARRAY_LENGTH case FLOAT => FARRAY_LENGTH case DOUBLE => DARRAY_LENGTH - case REFERENCE(_) | ARRAY(_) => OARRAY_LENGTH + case _: ClassBType | _: ArrayBType => OARRAY_LENGTH case _ => abort("Unexpected array element type: " + elementType) } diff --git a/src/compiler/scala/tools/nsc/backend/WorklistAlgorithm.scala b/src/compiler/scala/tools/nsc/backend/WorklistAlgorithm.scala deleted file mode 100644 index 45ca39fee4..0000000000 --- a/src/compiler/scala/tools/nsc/backend/WorklistAlgorithm.scala +++ /dev/null @@ -1,51 +0,0 @@ -/* NSC -- new Scala compiler - * Copyright 2005-2013 LAMP/EPFL - * @author Martin Odersky - */ - -package scala.tools.nsc -package backend - -import scala.collection.mutable - -/** - * Simple implementation of a worklist algorithm. A processing - * function is applied repeatedly to the first element in the - * worklist, as long as the stack is not empty. - * - * The client class should mix-in this class and initialize the worklist - * field and define the `processElement` method. Then call the `run` method - * providing a function that initializes the worklist. - * - * @author Martin Odersky - * @version 1.0 - * @see [[scala.tools.nsc.backend.icode.Linearizers]] - */ -trait WorklistAlgorithm { - type Elem - type WList = mutable.Stack[Elem] - - val worklist: WList - - /** - * Run the iterative algorithm until the worklist remains empty. - * The initializer is run once before the loop starts and should - * initialize the worklist. - */ - def run(initWorklist: => Unit) = { - initWorklist - - while (worklist.nonEmpty) - processElement(dequeue) - } - - /** - * Process the current element from the worklist. - */ - def processElement(e: Elem): Unit - - /** - * Remove and return the first element to be processed from the worklist. - */ - def dequeue: Elem -} diff --git a/src/compiler/scala/tools/nsc/backend/icode/BasicBlocks.scala b/src/compiler/scala/tools/nsc/backend/icode/BasicBlocks.scala deleted file mode 100644 index ad1975ef23..0000000000 --- a/src/compiler/scala/tools/nsc/backend/icode/BasicBlocks.scala +++ /dev/null @@ -1,553 +0,0 @@ -/* NSC -- new Scala compiler - * Copyright 2005-2013 LAMP/EPFL - * @author Martin Odersky - */ - -package scala.tools.nsc -package backend -package icode - -import scala.collection.{ mutable, immutable } -import mutable.ListBuffer -import backend.icode.analysis.ProgramPoint -import scala.language.postfixOps - -trait BasicBlocks { - self: ICodes => - - import opcodes._ - import global._ - - /** Override Array creation for efficiency (to not go through reflection). */ - private implicit val instructionTag: scala.reflect.ClassTag[Instruction] = new scala.reflect.ClassTag[Instruction] { - def runtimeClass: java.lang.Class[Instruction] = classOf[Instruction] - final override def newArray(len: Int): Array[Instruction] = new Array[Instruction](len) - } - - object NoBasicBlock extends BasicBlock(-1, null) - - /** This class represents a basic block. Each - * basic block contains a list of instructions that are - * either executed all, or none. No jumps - * to/from the "middle" of the basic block are allowed (modulo exceptions). - */ - class BasicBlock(val label: Int, val method: IMethod) extends ProgramPoint[BasicBlock] { - outer => - - import BBFlags._ - - def code = if (method eq null) NoCode else method.code - - private final class SuccessorList() { - private var successors: List[BasicBlock] = Nil - /** This method is very hot! Handle with care. */ - private def updateConserve() { - var lb: ListBuffer[BasicBlock] = null - var matches = 0 - var remaining = successors - val direct = directSuccessors - var scratchHandlers: List[ExceptionHandler] = method.exh - var scratchBlocks: List[BasicBlock] = direct - - def addBlock(bb: BasicBlock) { - if (matches < 0) - lb += bb - else if (remaining.isEmpty || bb != remaining.head) { - lb = ListBuffer[BasicBlock]() ++= (successors take matches) += bb - matches = -1 - } - else { - matches += 1 - remaining = remaining.tail - } - } - - while (scratchBlocks ne Nil) { - addBlock(scratchBlocks.head) - scratchBlocks = scratchBlocks.tail - } - /* Return a list of successors for 'b' that come from exception handlers - * covering b's (non-exceptional) successors. These exception handlers - * might not cover 'b' itself. This situation corresponds to an - * exception being thrown as the first thing of one of b's successors. - */ - while (scratchHandlers ne Nil) { - val handler = scratchHandlers.head - if (handler covers outer) - addBlock(handler.startBlock) - - scratchBlocks = direct - while (scratchBlocks ne Nil) { - if (handler covers scratchBlocks.head) - addBlock(handler.startBlock) - scratchBlocks = scratchBlocks.tail - } - scratchHandlers = scratchHandlers.tail - } - // Blocks did not align: create a new list. - if (matches < 0) - successors = lb.toList - // Blocks aligned, but more blocks remain. Take a prefix of the list. - else if (remaining.nonEmpty) - successors = successors take matches - // Otherwise the list is unchanged, leave it alone. - } - - /** This is called millions of times: it is performance sensitive. */ - def updateSuccs() { - if (isEmpty) { - if (successors.nonEmpty) - successors = Nil - } - else updateConserve() - } - def toList = successors - } - - /** Flags of this basic block. */ - private[this] var flags: Int = 0 - - /** Does this block have the given flag? */ - def hasFlag(flag: Int): Boolean = (flags & flag) != 0 - - /** Set the given flag. */ - private def setFlag(flag: Int): Unit = flags |= flag - private def resetFlag(flag: Int) { - flags &= ~flag - } - - /** Is this block closed? */ - def closed: Boolean = hasFlag(CLOSED) - def closed_=(b: Boolean) = if (b) setFlag(CLOSED) else resetFlag(CLOSED) - - /** When set, the `emit` methods will be ignored. */ - def ignore: Boolean = hasFlag(IGNORING) - def ignore_=(b: Boolean) = if (b) setFlag(IGNORING) else resetFlag(IGNORING) - - /** Is this block the head of a while? */ - def loopHeader = hasFlag(LOOP_HEADER) - def loopHeader_=(b: Boolean) = - if (b) setFlag(LOOP_HEADER) else resetFlag(LOOP_HEADER) - - /** Is this block the start block of an exception handler? */ - def exceptionHandlerStart = hasFlag(EX_HEADER) - def exceptionHandlerStart_=(b: Boolean) = - if (b) setFlag(EX_HEADER) else resetFlag(EX_HEADER) - - /** Has this basic block been modified since the last call to 'successors'? */ - def touched = hasFlag(DIRTYSUCCS) - def touched_=(b: Boolean) = if (b) { - setFlag(DIRTYSUCCS | DIRTYPREDS) - } else { - resetFlag(DIRTYSUCCS | DIRTYPREDS) - } - - // basic blocks start in a dirty state - setFlag(DIRTYSUCCS | DIRTYPREDS) - - /** Cached predecessors. */ - var preds: List[BasicBlock] = Nil - - /** Local variables that are in scope at entry of this basic block. Used - * for debugging information. - */ - val varsInScope: mutable.Set[Local] = new mutable.LinkedHashSet() - - /** ICode instructions, used as temporary storage while emitting code. - * Once closed is called, only the `instrs` array should be used. - */ - private var instructionList: List[Instruction] = Nil - private var instrs: Array[Instruction] = _ - - def take(n: Int): Seq[Instruction] = - if (closed) instrs take n else instructionList takeRight n reverse - - def toList: List[Instruction] = - if (closed) instrs.toList else instructionList.reverse - - /** Return an iterator over the instructions in this basic block. */ - def iterator: Iterator[Instruction] = - if (closed) instrs.iterator else instructionList.reverseIterator - - /** return the underlying array of instructions */ - def getArray: Array[Instruction] = { - assert(closed, this) - instrs - } - - def fromList(is: List[Instruction]) { - code.touched = true - instrs = is.toArray - closed = true - } - - /** Return the index of inst. Uses reference equality. - * Returns -1 if not found. - */ - def indexOf(inst: Instruction): Int = { - assert(closed, this) - instrs indexWhere (_ eq inst) - } - - /** Apply a function to all the instructions of the block. */ - final def foreach[U](f: Instruction => U) = { - if (!closed) dumpMethodAndAbort(method, this) - else instrs foreach f - - // !!! If I replace "instrs foreach f" with the following: - // var i = 0 - // val len = instrs.length - // while (i < len) { - // f(instrs(i)) - // i += 1 - // } - // - // Then when compiling under -optimise, quick.plugins fails as follows: - // - // quick.plugins: - // [mkdir] Created dir: /scratch/trunk6/build/quick/classes/continuations-plugin - // [scalacfork] Compiling 5 files to /scratch/trunk6/build/quick/classes/continuations-plugin - // [scalacfork] error: java.lang.VerifyError: (class: scala/tools/nsc/typechecker/Implicits$ImplicitSearch, method: typedImplicit0 signature: (Lscala/tools/nsc/typechecker/Implicits$ImplicitInfo;Z)Lscala/tools/nsc/typechecker/Implicits$SearchResult;) Incompatible object argument for function call - // [scalacfork] at scala.tools.nsc.typechecker.Implicits$class.inferImplicit(Implicits.scala:67) - // [scalacfork] at scala.tools.nsc.Global$$anon$1.inferImplicit(Global.scala:419) - // [scalacfork] at scala.tools.nsc.typechecker.Typers$Typer.wrapImplicit$1(Typers.scala:170) - // [scalacfork] at scala.tools.nsc.typechecker.Typers$Typer.inferView(Typers.scala:174) - // [scalacfork] at scala.tools.nsc.typechecker.Typers$Typer.adapt(Typers.scala:963) - // [scalacfork] at scala.tools.nsc.typechecker.Typers$Typer.typed(Typers.scala:4378) - // - // This is bad and should be understood/eliminated. - } - - /** The number of instructions in this basic block so far. */ - def length = if (closed) instrs.length else instructionList.length - def size = length - - /** Return the n-th instruction. */ - def apply(n: Int): Instruction = - if (closed) instrs(n) else instructionList.reverse(n) - - ///////////////////// Substitutions /////////////////////// - - /** - * Replace the instruction at the given position. Used by labels when they are anchored. - * The replacing instruction is given the nsc.util.Position of the instruction it replaces. - */ - def replaceInstruction(pos: Int, instr: Instruction): Boolean = { - assert(closed, "Instructions can be replaced only after the basic block is closed") - instr.setPos(instrs(pos).pos) - instrs(pos) = instr - code.touched = true - true - } - - /** - * Replace the given instruction with the new one. - * Returns `true` if it actually changed something. - * The replacing instruction is given the nsc.util.Position of the instruction it replaces. - */ - def replaceInstruction(oldInstr: Instruction, newInstr: Instruction): Boolean = { - assert(closed, "Instructions can be replaced only after the basic block is closed") - - indexOf(oldInstr) match { - case -1 => false - case idx => - newInstr setPos oldInstr.pos - instrs(idx) = newInstr - code.touched = true - true - } - } - - /** Replaces `oldInstr` with `is`. It does not update - * the position field in the newly inserted instructions, so it behaves - * differently than the one-instruction versions of this function. - */ - def replaceInstruction(oldInstr: Instruction, is: List[Instruction]): Boolean = { - assert(closed, "Instructions can be replaced only after the basic block is closed") - - indexOf(oldInstr) match { - case -1 => false - case idx => - instrs = instrs.patch(idx, is, 1) - code.touched = true - true - } - } - - /** Removes instructions found at the given positions. - */ - def removeInstructionsAt(positions: Int*) { - assert(closed, this) - instrs = instrs.indices.toArray filterNot positions.toSet map instrs - code.touched = true - } - - /** Remove the last instruction of this basic block. It is - * fast for an open block, but slower when the block is closed. - */ - def removeLastInstruction() { - if (closed) - removeInstructionsAt(length) - else { - instructionList = instructionList.tail - code.touched = true - } - } - - /** Replaces all instructions found in the map. - */ - def subst(map: Map[Instruction, Instruction]): Unit = - if (!closed) - instructionList = instructionList map (x => map.getOrElse(x, x)) - else - instrs.iterator.zipWithIndex foreach { - case (oldInstr, i) => - if (map contains oldInstr) { - // SI-6288 clone important here because `replaceInstruction` assigns - // a position to `newInstr`. Without this, a single instruction can - // be added twice, and the position last position assigned clobbers - // all previous positions in other usages. - val newInstr = map(oldInstr).clone() - code.touched |= replaceInstruction(i, newInstr) - } - } - - ////////////////////// Emit ////////////////////// - - - /** Add a new instruction at the end of the block, - * using the same source position as the last emitted instruction - */ - def emit(instr: Instruction) { - val pos = if (instructionList.isEmpty) NoPosition else instructionList.head.pos - emit(instr, pos) - } - - /** Emitting does not set touched to true. During code generation this is a hotspot and - * setting the flag for each emit is a waste. Caching should happen only after a block - * is closed, which sets the DIRTYSUCCS flag. - */ - def emit(instr: Instruction, pos: Position) { - assert(!closed || ignore, this) - - if (ignore) { - if (settings.debug) { - /* Trying to pin down what it's likely to see after a block has been - * put into ignore mode so we hear about it if there's a problem. - */ - instr match { - case JUMP(_) | RETURN(_) | THROW(_) | SCOPE_EXIT(_) => // ok - case STORE_LOCAL(local) if nme.isExceptionResultName(local.sym.name) => // ok - case x => log("Ignoring instruction, possibly at our peril, at " + pos + ": " + x) - } - } - } - else { - instr.setPos(pos) - instructionList ::= instr - } - } - - def emit(is: Seq[Instruction]) { - is foreach (i => emit(i, i.pos)) - } - - /** The semantics of this are a little odd but it's designed to work - * seamlessly with the existing code. It emits each supplied instruction, - * then closes the block. The odd part is that if the instruction has - * pos == NoPosition, it calls the 1-arg emit, but otherwise it calls - * the 2-arg emit. This way I could retain existing behavior exactly by - * calling setPos on any instruction using the two arg version which - * I wanted to include in a call to emitOnly. - */ - def emitOnly(is: Instruction*) { - is foreach (i => if (i.pos == NoPosition) emit(i) else emit(i, i.pos)) - this.close() - } - - /** do nothing if block is already closed */ - def closeWith(instr: Instruction) { - if (!closed) { - emit(instr) - close() - } - } - - def closeWith(instr: Instruction, pos: Position) { - if (!closed) { - emit(instr, pos) - close() - } - } - - /** Close the block */ - def close() { - assert(!closed || ignore, this) - if (ignore && closed) { // redundant `ignore &&` for clarity -- we should never be in state `!ignore && closed` - // not doing anything to this block is important... - // because the else branch reverses innocent blocks, which is wrong when they're in ignore mode (and closed) - // reversing the instructions when (closed && ignore) wreaks havoc for nested label jumps (see comments in genLoad) - } else { - closed = true - setFlag(DIRTYSUCCS) - instructionList = instructionList.reverse - instrs = instructionList.toArray - if (instructionList.isEmpty) { - debuglog(s"Removing empty block $this") - code removeBlock this - } - } - } - - /** - * if cond is true, closes this block, entersIgnoreMode, and removes the block from - * its list of blocks. Used to allow a block to be started and then cancelled when it - * is discovered to be unreachable. - */ - def killIf(cond: Boolean) { - if (!settings.YdisableUnreachablePrevention && cond) { - debuglog(s"Killing block $this") - assert(instructionList.isEmpty, s"Killing a non empty block $this") - // only checked under debug because fetching predecessor list is moderately expensive - if (settings.debug) - assert(predecessors.isEmpty, s"Killing block $this which is referred to from ${predecessors.mkString}") - - close() - enterIgnoreMode() - } - } - - /** - * Same as killIf but with the logic of the condition reversed - */ - def killUnless(cond: Boolean) { - this killIf !cond - } - - def open() { - assert(closed, this) - closed = false - ignore = false - touched = true - instructionList = instructionList.reverse // prepare for appending to the head - } - - def clear() { - instructionList = Nil - instrs = null - preds = Nil - } - - final def isEmpty = instructionList.isEmpty - final def nonEmpty = !isEmpty - - /** Enter ignore mode: new 'emit'ted instructions will not be - * added to this basic block. It makes the generation of THROW - * and RETURNs easier. - */ - def enterIgnoreMode() = { - ignore = true - } - - /** Return the last instruction of this basic block. */ - def lastInstruction = - if (closed) instrs(instrs.length - 1) - else instructionList.head - - def exceptionSuccessors: List[BasicBlock] = - exceptionSuccessorsForBlock(this) - - def exceptionSuccessorsForBlock(block: BasicBlock): List[BasicBlock] = - method.exh collect { case x if x covers block => x.startBlock } - - /** Cached value of successors. Must be recomputed whenever a block in the current method is changed. */ - private val succs = new SuccessorList - - def successors: List[BasicBlock] = { - if (touched) { - succs.updateSuccs() - resetFlag(DIRTYSUCCS) - } - succs.toList - } - - def directSuccessors: List[BasicBlock] = - if (isEmpty) Nil else lastInstruction match { - case JUMP(whereto) => whereto :: Nil - case CJUMP(succ, fail, _, _) => fail :: succ :: Nil - case CZJUMP(succ, fail, _, _) => fail :: succ :: Nil - case SWITCH(_, labels) => labels - case RETURN(_) => Nil - case THROW(_) => Nil - case _ => - if (closed) - devWarning(s"$lastInstruction/${lastInstruction.getClass.getName} is not a control flow instruction") - - Nil - } - - /** Returns the predecessors of this block. */ - def predecessors: List[BasicBlock] = { - if (hasFlag(DIRTYPREDS)) { - resetFlag(DIRTYPREDS) - preds = code.blocks.iterator filter (_.successors contains this) toList - } - preds - } - - override def equals(other: Any): Boolean = other match { - case that: BasicBlock => (that.label == label) && (that.code == code) - case _ => false - } - - override def hashCode = label * 41 + code.hashCode - - private def succString = if (successors.isEmpty) "[S: N/A]" else successors.distinct.mkString("[S: ", ", ", "]") - private def predString = if (predecessors.isEmpty) "[P: N/A]" else predecessors.distinct.mkString("[P: ", ", ", "]") - - override def toString(): String = "" + label - - def blockContents = { - def posStr(p: Position) = if (p.isDefined) p.line.toString else "<??>" - val xs = this.toList map (instr => posStr(instr.pos) + "\t" + instr) - xs.mkString(fullString + " {\n ", "\n ", "\n}") - } - def predContents = predecessors.map(_.blockContents).mkString(predecessors.size + " preds:\n", "\n", "\n") - def succContents = successors.map(_.blockContents).mkString(successors.size + " succs:\n", "\n", "\n") - - def fullString: String = List("Block", label, succString, predString, flagsString) mkString " " - def flagsString: String = BBFlags.flagsToString(flags) - } -} - -object BBFlags { - /** This block is a loop header (was translated from a while). */ - final val LOOP_HEADER = (1 << 0) - - /** Ignoring mode: emit instructions are dropped. */ - final val IGNORING = (1 << 1) - - /** This block is the header of an exception handler. */ - final val EX_HEADER = (1 << 2) - - /** This block is closed. No new instructions can be added. */ - final val CLOSED = (1 << 3) - - /** Code has been changed, recompute successors. */ - final val DIRTYSUCCS = (1 << 4) - - /** Code has been changed, recompute predecessors. */ - final val DIRTYPREDS = (1 << 5) - - val flagMap = Map[Int, String]( - LOOP_HEADER -> "loopheader", - IGNORING -> "ignore", - EX_HEADER -> "exheader", - CLOSED -> "closed", - DIRTYSUCCS -> "dirtysuccs", - DIRTYPREDS -> "dirtypreds" - ) - def flagsToString(flags: Int) = { - flagMap collect { case (bit, name) if (bit & flags) != 0 => "<" + name + ">" } mkString " " - } -} diff --git a/src/compiler/scala/tools/nsc/backend/icode/CheckerException.scala b/src/compiler/scala/tools/nsc/backend/icode/CheckerException.scala deleted file mode 100644 index 8bcdb6dbd2..0000000000 --- a/src/compiler/scala/tools/nsc/backend/icode/CheckerException.scala +++ /dev/null @@ -1,10 +0,0 @@ -/* NSC -- new Scala compiler - * Copyright 2005-2013 LAMP/EPFL - * @author Martin Odersky - */ - -package scala.tools.nsc -package backend -package icode - -class CheckerException(s: String) extends Exception(s) diff --git a/src/compiler/scala/tools/nsc/backend/icode/ExceptionHandlers.scala b/src/compiler/scala/tools/nsc/backend/icode/ExceptionHandlers.scala deleted file mode 100644 index 7243264773..0000000000 --- a/src/compiler/scala/tools/nsc/backend/icode/ExceptionHandlers.scala +++ /dev/null @@ -1,71 +0,0 @@ -/* NSC -- new scala compiler - * Copyright 2005-2013 LAMP/EPFL - * @author Martin Odersky - */ - -package scala.tools.nsc -package backend -package icode - -import scala.collection.immutable - -/** - * Exception handlers are pieces of code that `handle` exceptions on - * the covered basic blocks. Since Scala's exception handling uses - * pattern matching instead of just class names to identify handlers, - * all our handlers will catch `Throwable` and rely on proper ordering - * in the generated code to preserve nesting. - */ -trait ExceptionHandlers { - self: ICodes => - - import global._ - import definitions.{ ThrowableClass } - - class ExceptionHandler(val method: IMethod, val label: TermName, val cls: Symbol, val pos: Position) { - def loadExceptionClass = if (cls == NoSymbol) ThrowableClass else cls - private var _startBlock: BasicBlock = _ - var finalizer: Finalizer = _ - - def setStartBlock(b: BasicBlock) = { - _startBlock = b - b.exceptionHandlerStart = true - } - def startBlock = _startBlock - - /** The list of blocks that are covered by this exception handler */ - var covered: immutable.Set[BasicBlock] = immutable.HashSet.empty[BasicBlock] - - def addCoveredBlock(b: BasicBlock): this.type = { - covered = covered + b - this - } - - /** Is `b` covered by this exception handler? */ - def covers(b: BasicBlock): Boolean = covered(b) - - /** The body of this exception handler. May contain 'dead' blocks (which will not - * make it into generated code because linearizers may not include them) */ - var blocks: List[BasicBlock] = Nil - - def addBlock(b: BasicBlock): Unit = blocks = b :: blocks - - override def toString() = "exh_" + label + "(" + cls.simpleName + ")" - - /** A standard copy constructor */ - def this(other: ExceptionHandler) = { - this(other.method, other.label, other.cls, other.pos) - - covered = other.covered - setStartBlock(other.startBlock) - finalizer = other.finalizer - } - - def dup: ExceptionHandler = new ExceptionHandler(this) - } - - class Finalizer(method: IMethod, label: TermName, pos: Position) extends ExceptionHandler(method, label, NoSymbol, pos) { - override def toString() = "finalizer_" + label - override def dup: Finalizer = new Finalizer(method, label, pos) - } -} diff --git a/src/compiler/scala/tools/nsc/backend/icode/GenICode.scala b/src/compiler/scala/tools/nsc/backend/icode/GenICode.scala deleted file mode 100644 index b6f9bcc9ab..0000000000 --- a/src/compiler/scala/tools/nsc/backend/icode/GenICode.scala +++ /dev/null @@ -1,2239 +0,0 @@ -/* NSC -- new Scala compiler - * Copyright 2005-2013 LAMP/EPFL - * @author Martin Odersky - */ - - -package scala -package tools.nsc -package backend -package icode - -import scala.collection.{ mutable, immutable } -import scala.collection.mutable.{ ListBuffer, Buffer } -import scala.tools.nsc.symtab._ -import scala.annotation.switch - -/** - * @author Iulian Dragos - * @version 1.0 - */ -abstract class GenICode extends SubComponent { - import global._ - import icodes._ - import icodes.opcodes._ - import definitions._ - import scalaPrimitives.{ - isArrayOp, isComparisonOp, isLogicalOp, - isUniversalEqualityOp, isReferenceEqualityOp - } - import platform.isMaybeBoxed - - private val bCodeICodeCommon: jvm.BCodeICodeCommon[global.type] = new jvm.BCodeICodeCommon(global) - import bCodeICodeCommon._ - - val phaseName = "icode" - - override def newPhase(prev: Phase) = new ICodePhase(prev) - - @inline private def debugassert(cond: => Boolean, msg: => Any) { - if (settings.debug) - assert(cond, msg) - } - - class ICodePhase(prev: Phase) extends StdPhase(prev) { - - override def description = "Generate ICode from the AST" - - var unit: CompilationUnit = NoCompilationUnit - - override def run() { - if (!settings.isBCodeActive) { - scalaPrimitives.init() - classes.clear() - } - super.run() - } - - override def apply(unit: CompilationUnit): Unit = { - if (settings.isBCodeActive) { return } - this.unit = unit - unit.icode.clear() - informProgress("Generating icode for " + unit) - gen(unit.body) - this.unit = NoCompilationUnit - } - - def gen(tree: Tree): Context = gen(tree, new Context()) - - def gen(trees: List[Tree], ctx: Context): Context = { - var ctx1 = ctx - for (t <- trees) ctx1 = gen(t, ctx1) - ctx1 - } - - /** If the selector type has a member with the right name, - * it is the host class; otherwise the symbol's owner. - */ - def findHostClass(selector: Type, sym: Symbol) = selector member sym.name match { - case NoSymbol => debuglog(s"Rejecting $selector as host class for $sym") ; sym.owner - case _ => selector.typeSymbol - } - - /////////////////// Code generation /////////////////////// - - def gen(tree: Tree, ctx: Context): Context = tree match { - case EmptyTree => ctx - - case PackageDef(pid, stats) => - gen(stats, ctx setPackage pid.name) - - case ClassDef(mods, name, _, impl) => - debuglog("Generating class: " + tree.symbol.fullName) - val outerClass = ctx.clazz - ctx setClass (new IClass(tree.symbol) setCompilationUnit unit) - addClassFields(ctx, tree.symbol) - classes += (tree.symbol -> ctx.clazz) - unit.icode += ctx.clazz - gen(impl, ctx) - ctx.clazz.methods = ctx.clazz.methods.reverse // preserve textual order - ctx.clazz.fields = ctx.clazz.fields.reverse // preserve textual order - ctx setClass outerClass - - // !! modules should be eliminated by refcheck... or not? - case ModuleDef(mods, name, impl) => - abort("Modules should not reach backend! " + tree) - - case ValDef(mods, name, tpt, rhs) => - ctx // we use the symbol to add fields - - case DefDef(mods, name, tparams, vparamss, tpt, rhs) => - debuglog("Entering method " + name) - val m = new IMethod(tree.symbol) - m.sourceFile = unit.source - m.returnType = if (tree.symbol.isConstructor) UNIT - else toTypeKind(tree.symbol.info.resultType) - ctx.clazz.addMethod(m) - - var ctx1 = ctx.enterMethod(m, tree.asInstanceOf[DefDef]) - addMethodParams(ctx1, vparamss) - m.native = m.symbol.hasAnnotation(definitions.NativeAttr) - - if (!m.isAbstractMethod && !m.native) { - ctx1 = genLoad(rhs, ctx1, m.returnType) - - // reverse the order of the local variables, to match the source-order - m.locals = m.locals.reverse - - rhs match { - case Block(_, Return(_)) => () - case Return(_) => () - case EmptyTree => - globalError("Concrete method has no definition: " + tree + ( - if (settings.debug) "(found: " + m.symbol.owner.info.decls.toList.mkString(", ") + ")" - else "") - ) - case _ => if (ctx1.bb.isEmpty) - ctx1.bb.closeWith(RETURN(m.returnType), rhs.pos) - else - ctx1.bb.closeWith(RETURN(m.returnType)) - } - if (!ctx1.bb.closed) ctx1.bb.close() - prune(ctx1.method) - } else - ctx1.method.setCode(NoCode) - ctx1 - - case Template(_, _, body) => - gen(body, ctx) - - case _ => - abort("Illegal tree in gen: " + tree) - } - - private def genStat(trees: List[Tree], ctx: Context): Context = - trees.foldLeft(ctx)((currentCtx, t) => genStat(t, currentCtx)) - - /** - * Generate code for the given tree. The trees should contain statements - * and not produce any value. Use genLoad for expressions which leave - * a value on top of the stack. - * - * @return a new context. This is necessary for control flow instructions - * which may change the current basic block. - */ - private def genStat(tree: Tree, ctx: Context): Context = tree match { - case Assign(lhs @ Select(_, _), rhs) => - val isStatic = lhs.symbol.isStaticMember - var ctx1 = if (isStatic) ctx else genLoadQualifier(lhs, ctx) - - ctx1 = genLoad(rhs, ctx1, toTypeKind(lhs.symbol.info)) - ctx1.bb.emit(STORE_FIELD(lhs.symbol, isStatic), tree.pos) - ctx1 - - case Assign(lhs, rhs) => - val ctx1 = genLoad(rhs, ctx, toTypeKind(lhs.symbol.info)) - val Some(l) = ctx.method.lookupLocal(lhs.symbol) - ctx1.bb.emit(STORE_LOCAL(l), tree.pos) - ctx1 - - case _ => - genLoad(tree, ctx, UNIT) - } - - private def genThrow(expr: Tree, ctx: Context): (Context, TypeKind) = { - require(expr.tpe <:< ThrowableTpe, expr.tpe) - - val thrownKind = toTypeKind(expr.tpe) - val ctx1 = genLoad(expr, ctx, thrownKind) - ctx1.bb.emit(THROW(expr.tpe.typeSymbol), expr.pos) - ctx1.bb.enterIgnoreMode() - - (ctx1, NothingReference) - } - - /** - * Generate code for primitive arithmetic operations. - * Returns (Context, Generated Type) - */ - private def genArithmeticOp(tree: Tree, ctx: Context, code: Int): (Context, TypeKind) = { - val Apply(fun @ Select(larg, _), args) = tree - var ctx1 = ctx - var resKind = toTypeKind(larg.tpe) - - debugassert(args.length <= 1, - "Too many arguments for primitive function: " + fun.symbol) - debugassert(resKind.isNumericType | resKind == BOOL, - resKind.toString() + " is not a numeric or boolean type " + - "[operation: " + fun.symbol + "]") - - args match { - // unary operation - case Nil => - ctx1 = genLoad(larg, ctx1, resKind) - code match { - case scalaPrimitives.POS => - () // nothing - case scalaPrimitives.NEG => - ctx1.bb.emit(CALL_PRIMITIVE(Negation(resKind)), larg.pos) - case scalaPrimitives.NOT => - ctx1.bb.emit(CALL_PRIMITIVE(Arithmetic(NOT, resKind)), larg.pos) - case _ => - abort("Unknown unary operation: " + fun.symbol.fullName + - " code: " + code) - } - - // binary operation - case rarg :: Nil => - resKind = getMaxType(larg.tpe :: rarg.tpe :: Nil) - if (scalaPrimitives.isShiftOp(code) || scalaPrimitives.isBitwiseOp(code)) - assert(resKind.isIntegralType | resKind == BOOL, - resKind.toString() + " incompatible with arithmetic modulo operation: " + ctx1) - - ctx1 = genLoad(larg, ctx1, resKind) - ctx1 = genLoad(rarg, - ctx1, // check .NET size of shift arguments! - if (scalaPrimitives.isShiftOp(code)) INT else resKind) - - val primitiveOp = code match { - case scalaPrimitives.ADD => Arithmetic(ADD, resKind) - case scalaPrimitives.SUB => Arithmetic(SUB, resKind) - case scalaPrimitives.MUL => Arithmetic(MUL, resKind) - case scalaPrimitives.DIV => Arithmetic(DIV, resKind) - case scalaPrimitives.MOD => Arithmetic(REM, resKind) - case scalaPrimitives.OR => Logical(OR, resKind) - case scalaPrimitives.XOR => Logical(XOR, resKind) - case scalaPrimitives.AND => Logical(AND, resKind) - case scalaPrimitives.LSL => Shift(LSL, resKind) - case scalaPrimitives.LSR => Shift(LSR, resKind) - case scalaPrimitives.ASR => Shift(ASR, resKind) - case _ => abort("Unknown primitive: " + fun.symbol + "[" + code + "]") - } - ctx1.bb.emit(CALL_PRIMITIVE(primitiveOp), tree.pos) - - case _ => - abort("Too many arguments for primitive function: " + tree) - } - (ctx1, resKind) - } - - /** Generate primitive array operations. - */ - private def genArrayOp(tree: Tree, ctx: Context, code: Int, expectedType: TypeKind): (Context, TypeKind) = { - import scalaPrimitives._ - val Apply(Select(arrayObj, _), args) = tree - val k = toTypeKind(arrayObj.tpe) - val ARRAY(elem) = k - var ctx1 = genLoad(arrayObj, ctx, k) - val elementType = typeOfArrayOp.getOrElse(code, abort("Unknown operation on arrays: " + tree + " code: " + code)) - - var generatedType = expectedType - - if (scalaPrimitives.isArrayGet(code)) { - // load argument on stack - debugassert(args.length == 1, - "Too many arguments for array get operation: " + tree) - ctx1 = genLoad(args.head, ctx1, INT) - generatedType = elem - ctx1.bb.emit(LOAD_ARRAY_ITEM(elementType), tree.pos) - // it's tempting to just drop array loads of type Null instead - // of adapting them but array accesses can cause - // ArrayIndexOutOfBounds so we can't. Besides, Array[Null] - // probably isn't common enough to figure out an optimization - adaptNullRef(generatedType, expectedType, ctx1, tree.pos) - } - else if (scalaPrimitives.isArraySet(code)) { - debugassert(args.length == 2, - "Too many arguments for array set operation: " + tree) - ctx1 = genLoad(args.head, ctx1, INT) - ctx1 = genLoad(args.tail.head, ctx1, toTypeKind(args.tail.head.tpe)) - // the following line should really be here, but because of bugs in erasure - // we pretend we generate whatever type is expected from us. - //generatedType = UNIT - - ctx1.bb.emit(STORE_ARRAY_ITEM(elementType), tree.pos) - } - else { - generatedType = INT - ctx1.bb.emit(CALL_PRIMITIVE(ArrayLength(elementType)), tree.pos) - } - - (ctx1, generatedType) - } - private def genSynchronized(tree: Apply, ctx: Context, expectedType: TypeKind): (Context, TypeKind) = { - val Apply(fun, args) = tree - val monitor = ctx.makeLocal(tree.pos, ObjectTpe, "monitor") - var monitorResult: Local = null - val argTpe = args.head.tpe - val hasResult = expectedType != UNIT - if (hasResult) - monitorResult = ctx.makeLocal(tree.pos, argTpe, "monitorResult") - - var ctx1 = genLoadQualifier(fun, ctx) - ctx1.bb.emit(Seq( - DUP(ObjectReference), - STORE_LOCAL(monitor), - MONITOR_ENTER() setPos tree.pos - )) - ctx1.enterSynchronized(monitor) - debuglog("synchronized block start") - - ctx1 = ctx1.Try( - bodyCtx => { - val ctx2 = genLoad(args.head, bodyCtx, expectedType /* toTypeKind(tree.tpe.resultType) */) - if (hasResult) - ctx2.bb.emit(STORE_LOCAL(monitorResult)) - ctx2.bb.emit(Seq( - LOAD_LOCAL(monitor), - MONITOR_EXIT() setPos tree.pos - )) - ctx2 - }, List( - // tree.tpe / fun.tpe is object, which is no longer true after this transformation - (ThrowableClass, expectedType, exhCtx => { - exhCtx.bb.emit(Seq( - LOAD_LOCAL(monitor), - MONITOR_EXIT() setPos tree.pos, - THROW(ThrowableClass) - )) - exhCtx.bb.enterIgnoreMode() - exhCtx - })), EmptyTree, tree) - - debuglog("synchronized block end with block %s closed=%s".format(ctx1.bb, ctx1.bb.closed)) - ctx1.exitSynchronized(monitor) - if (hasResult) - ctx1.bb.emit(LOAD_LOCAL(monitorResult)) - (ctx1, expectedType) - } - - private def genLoadIf(tree: If, ctx: Context, expectedType: TypeKind): (Context, TypeKind) = { - val If(cond, thenp, elsep) = tree - - var thenCtx = ctx.newBlock() - var elseCtx = ctx.newBlock() - val contCtx = ctx.newBlock() - - genCond(cond, ctx, thenCtx, elseCtx) - - val ifKind = toTypeKind(tree.tpe) - val thenKind = toTypeKind(thenp.tpe) - val elseKind = if (elsep == EmptyTree) UNIT else toTypeKind(elsep.tpe) - - // we need to drop unneeded results, if one branch gives - // unit and the other gives something on the stack, because - // the type of 'if' is scala.Any, and its erasure would be Object. - // But unboxed units are not Objects... - def hasUnitBranch = thenKind == UNIT || elseKind == UNIT - val resKind = if (hasUnitBranch) UNIT else ifKind - - if (hasUnitBranch) - debuglog("Will drop result from an if branch") - - thenCtx = genLoad(thenp, thenCtx, resKind) - elseCtx = genLoad(elsep, elseCtx, resKind) - - debugassert(!hasUnitBranch || expectedType == UNIT, - "I produce UNIT in a context where " + expectedType + " is expected!") - - // alternatives may be already closed by a tail-recursive jump - val contReachable = !(thenCtx.bb.ignore && elseCtx.bb.ignore) - thenCtx.bb.closeWith(JUMP(contCtx.bb)) - elseCtx.bb.closeWith( - if (elsep == EmptyTree) JUMP(contCtx.bb) - else JUMP(contCtx.bb) setPos tree.pos - ) - - contCtx.bb killUnless contReachable - (contCtx, resKind) - } - private def genLoadTry(tree: Try, ctx: Context, setGeneratedType: TypeKind => Unit): Context = { - val Try(block, catches, finalizer) = tree - val kind = toTypeKind(tree.tpe) - - val caseHandlers = - for (CaseDef(pat, _, body) <- catches.reverse) yield { - def genWildcardHandler(sym: Symbol): (Symbol, TypeKind, Context => Context) = - (sym, kind, ctx => { - ctx.bb.emit(DROP(REFERENCE(sym))) // drop the loaded exception - genLoad(body, ctx, kind) - }) - - pat match { - case Typed(Ident(nme.WILDCARD), tpt) => genWildcardHandler(tpt.tpe.typeSymbol) - case Ident(nme.WILDCARD) => genWildcardHandler(ThrowableClass) - case Bind(_, _) => - val exception = ctx.method addLocal new Local(pat.symbol, toTypeKind(pat.symbol.tpe), false) // the exception will be loaded and stored into this local - - (pat.symbol.tpe.typeSymbol, kind, { - ctx: Context => - ctx.bb.emit(STORE_LOCAL(exception), pat.pos) - genLoad(body, ctx, kind) - }) - } - } - - ctx.Try( - bodyCtx => { - setGeneratedType(kind) - genLoad(block, bodyCtx, kind) - }, - caseHandlers, - finalizer, - tree) - } - - private def genPrimitiveOp(tree: Apply, ctx: Context, expectedType: TypeKind): (Context, TypeKind) = { - val sym = tree.symbol - val Apply(fun @ Select(receiver, _), _) = tree - val code = scalaPrimitives.getPrimitive(sym, receiver.tpe) - - if (scalaPrimitives.isArithmeticOp(code)) - genArithmeticOp(tree, ctx, code) - else if (code == scalaPrimitives.CONCAT) - (genStringConcat(tree, ctx), StringReference) - else if (code == scalaPrimitives.HASH) - (genScalaHash(receiver, ctx), INT) - else if (isArrayOp(code)) - genArrayOp(tree, ctx, code, expectedType) - else if (isLogicalOp(code) || isComparisonOp(code)) { - val trueCtx, falseCtx, afterCtx = ctx.newBlock() - - genCond(tree, ctx, trueCtx, falseCtx) - trueCtx.bb.emitOnly( - CONSTANT(Constant(true)) setPos tree.pos, - JUMP(afterCtx.bb) - ) - falseCtx.bb.emitOnly( - CONSTANT(Constant(false)) setPos tree.pos, - JUMP(afterCtx.bb) - ) - (afterCtx, BOOL) - } - else if (code == scalaPrimitives.SYNCHRONIZED) - genSynchronized(tree, ctx, expectedType) - else if (scalaPrimitives.isCoercion(code)) { - val ctx1 = genLoad(receiver, ctx, toTypeKind(receiver.tpe)) - genCoercion(tree, ctx1, code) - (ctx1, scalaPrimitives.generatedKind(code)) - } - else abort( - "Primitive operation not handled yet: " + sym.fullName + "(" + - fun.symbol.simpleName + ") " + " at: " + (tree.pos) - ) - } - - /** - * Generate code for trees that produce values on the stack - * - * @param tree The tree to be translated - * @param ctx The current context - * @param expectedType The type of the value to be generated on top of the - * stack. - * @return The new context. The only thing that may change is the current - * basic block (as the labels map is mutable). - */ - private def genLoad(tree: Tree, ctx: Context, expectedType: TypeKind): Context = { - var generatedType = expectedType - debuglog("at line: " + (if (tree.pos.isDefined) tree.pos.line else tree.pos)) - - val resCtx: Context = tree match { - case LabelDef(name, params, rhs) => - def genLoadLabelDef = { - val ctx1 = ctx.newBlock() // note: we cannot kill ctx1 if ctx is in ignore mode because - // label defs can be the target of jumps from other locations. - // that means label defs can lead to unreachable code without - // proper reachability analysis - - if (nme.isLoopHeaderLabel(name)) - ctx1.bb.loopHeader = true - - ctx1.labels.get(tree.symbol) match { - case Some(label) => - debuglog("Found existing label for " + tree.symbol.fullLocationString) - label.anchor(ctx1.bb) - label.patch(ctx.method.code) - - case None => - val pair = (tree.symbol -> (new Label(tree.symbol) anchor ctx1.bb setParams (params map (_.symbol)))) - debuglog("Adding label " + tree.symbol.fullLocationString + " in genLoad.") - ctx1.labels += pair - ctx.method.addLocals(params map (p => new Local(p.symbol, toTypeKind(p.symbol.info), false))) - } - - ctx.bb.closeWith(JUMP(ctx1.bb), tree.pos) - genLoad(rhs, ctx1, expectedType /*toTypeKind(tree.symbol.info.resultType)*/) - } - genLoadLabelDef - - case ValDef(_, name, _, rhs) => - def genLoadValDef = - if (name == nme.THIS) { - debuglog("skipping trivial assign to _$this: " + tree) - ctx - } else { - val sym = tree.symbol - val local = ctx.method.addLocal(new Local(sym, toTypeKind(sym.info), false)) - - if (rhs == EmptyTree) { - debuglog("Uninitialized variable " + tree + " at: " + (tree.pos)) - ctx.bb.emit(getZeroOf(local.kind)) - } - - var ctx1 = ctx - if (rhs != EmptyTree) - ctx1 = genLoad(rhs, ctx, local.kind) - - ctx1.bb.emit(STORE_LOCAL(local), tree.pos) - ctx1.scope.add(local) - ctx1.bb.emit(SCOPE_ENTER(local)) - generatedType = UNIT - ctx1 - } - genLoadValDef - - case t @ If(cond, thenp, elsep) => - val (newCtx, resKind) = genLoadIf(t, ctx, expectedType) - generatedType = resKind - newCtx - - case Return(expr) => - def genLoadReturn = { - val returnedKind = toTypeKind(expr.tpe) - debuglog("Return(" + expr + ") with returnedKind = " + returnedKind) - - var ctx1 = genLoad(expr, ctx, returnedKind) - lazy val tmp = ctx1.makeLocal(tree.pos, expr.tpe, "tmp") - val saved = savingCleanups(ctx1) { - var savedFinalizer = false - ctx1.cleanups foreach { - case MonitorRelease(m) => - debuglog("removing " + m + " from cleanups: " + ctx1.cleanups) - ctx1.bb.emit(Seq(LOAD_LOCAL(m), MONITOR_EXIT())) - ctx1.exitSynchronized(m) - - case Finalizer(f, finalizerCtx) => - debuglog("removing " + f + " from cleanups: " + ctx1.cleanups) - if (returnedKind != UNIT && mayCleanStack(f)) { - log("Emitting STORE_LOCAL for " + tmp + " to save finalizer.") - ctx1.bb.emit(STORE_LOCAL(tmp)) - savedFinalizer = true - } - - // duplicate finalizer (takes care of anchored labels) - val f1 = duplicateFinalizer(Set.empty ++ ctx1.labels.keySet, ctx1, f) - - // we have to run this without the same finalizer in - // the list, otherwise infinite recursion happens for - // finalizers that contain 'return' - val fctx = finalizerCtx.newBlock() - fctx.bb killIf ctx1.bb.ignore - ctx1.bb.closeWith(JUMP(fctx.bb)) - ctx1 = genLoad(f1, fctx, UNIT) - } - savedFinalizer - } - - if (saved) { - log("Emitting LOAD_LOCAL for " + tmp + " after saving finalizer.") - ctx1.bb.emit(LOAD_LOCAL(tmp)) - } - adapt(returnedKind, ctx1.method.returnType, ctx1, tree.pos) - ctx1.bb.emit(RETURN(ctx.method.returnType), tree.pos) - ctx1.bb.enterIgnoreMode() - generatedType = expectedType - ctx1 - } - genLoadReturn - - case t @ Try(_, _, _) => - genLoadTry(t, ctx, generatedType = _) - - case Throw(expr) => - val (ctx1, expectedType) = genThrow(expr, ctx) - generatedType = expectedType - ctx1 - - case New(tpt) => - abort("Unexpected New(" + tpt.summaryString + "/" + tpt + ") received in icode.\n" + - " Call was genLoad" + ((tree, ctx, expectedType))) - - case Apply(TypeApply(fun, targs), _) => - def genLoadApply1 = { - val sym = fun.symbol - val cast = sym match { - case Object_isInstanceOf => false - case Object_asInstanceOf => true - case _ => abort("Unexpected type application " + fun + "[sym: " + sym.fullName + "]" + " in: " + tree) - } - - val Select(obj, _) = fun - val l = toTypeKind(obj.tpe) - val r = toTypeKind(targs.head.tpe) - val ctx1 = genLoadQualifier(fun, ctx) - - if (l.isValueType && r.isValueType) - genConversion(l, r, ctx1, cast) - else if (l.isValueType) { - ctx1.bb.emit(DROP(l), fun.pos) - if (cast) { - ctx1.bb.emit(Seq( - NEW(REFERENCE(definitions.ClassCastExceptionClass)), - DUP(ObjectReference), - THROW(definitions.ClassCastExceptionClass) - )) - } else - ctx1.bb.emit(CONSTANT(Constant(false))) - } else if (r.isValueType && cast) { - /* Erasure should have added an unboxing operation to prevent that. */ - abort("should have been unboxed by erasure: " + tree) - } else if (r.isValueType) { - ctx.bb.emit(IS_INSTANCE(REFERENCE(definitions.boxedClass(r.toType.typeSymbol)))) - } else { - genCast(l, r, ctx1, cast) - } - generatedType = if (cast) r else BOOL - ctx1 - } - genLoadApply1 - - // 'super' call: Note: since constructors are supposed to - // return an instance of what they construct, we have to take - // special care. On JVM they are 'void', and Scala forbids (syntactically) - // to call super constructors explicitly and/or use their 'returned' value. - // therefore, we can ignore this fact, and generate code that leaves nothing - // on the stack (contrary to what the type in the AST says). - case Apply(fun @ Select(Super(_, mix), _), args) => - def genLoadApply2 = { - debuglog("Call to super: " + tree) - val invokeStyle = SuperCall(mix) - // if (fun.symbol.isConstructor) Static(true) else SuperCall(mix); - - ctx.bb.emit(THIS(ctx.clazz.symbol), tree.pos) - val ctx1 = genLoadArguments(args, fun.symbol.info.paramTypes, ctx) - - ctx1.bb.emit(CALL_METHOD(fun.symbol, invokeStyle), tree.pos) - generatedType = - if (fun.symbol.isConstructor) UNIT - else toTypeKind(fun.symbol.info.resultType) - ctx1 - } - genLoadApply2 - - // 'new' constructor call: Note: since constructors are - // thought to return an instance of what they construct, - // we have to 'simulate' it by DUPlicating the freshly created - // instance (on JVM, <init> methods return VOID). - case Apply(fun @ Select(New(tpt), nme.CONSTRUCTOR), args) => - def genLoadApply3 = { - val ctor = fun.symbol - debugassert(ctor.isClassConstructor, - "'new' call to non-constructor: " + ctor.name) - - generatedType = toTypeKind(tpt.tpe) - debugassert(generatedType.isReferenceType || generatedType.isArrayType, - "Non reference type cannot be instantiated: " + generatedType) - - generatedType match { - case arr @ ARRAY(elem) => - val ctx1 = genLoadArguments(args, ctor.info.paramTypes, ctx) - val dims = arr.dimensions - var elemKind = arr.elementKind - if (args.length > dims) - reporter.error(tree.pos, "too many arguments for array constructor: found " + args.length + - " but array has only " + dims + " dimension(s)") - if (args.length != dims) - for (i <- args.length until dims) elemKind = ARRAY(elemKind) - ctx1.bb.emit(CREATE_ARRAY(elemKind, args.length), tree.pos) - ctx1 - - case rt @ REFERENCE(cls) => - debugassert(ctor.owner == cls, - "Symbol " + ctor.owner.fullName + " is different than " + tpt) - - val nw = NEW(rt) - ctx.bb.emit(nw, tree.pos) - ctx.bb.emit(DUP(generatedType)) - val ctx1 = genLoadArguments(args, ctor.info.paramTypes, ctx) - - val init = CALL_METHOD(ctor, Static(onInstance = true)) - nw.init = init - ctx1.bb.emit(init, tree.pos) - ctx1 - case _ => - abort("Cannot instantiate " + tpt + " of kind: " + generatedType) - } - } - genLoadApply3 - - case Apply(fun @ _, List(expr)) if currentRun.runDefinitions.isBox(fun.symbol) => - def genLoadApply4 = { - debuglog("BOX : " + fun.symbol.fullName) - val ctx1 = genLoad(expr, ctx, toTypeKind(expr.tpe)) - val nativeKind = toTypeKind(expr.tpe) - if (settings.Xdce) { - // we store this boxed value to a local, even if not really needed. - // boxing optimization might use it, and dead code elimination will - // take care of unnecessary stores - val loc1 = ctx.makeLocal(tree.pos, expr.tpe, "boxed") - ctx1.bb.emit(STORE_LOCAL(loc1)) - ctx1.bb.emit(LOAD_LOCAL(loc1)) - } - ctx1.bb.emit(BOX(nativeKind), expr.pos) - generatedType = toTypeKind(fun.symbol.tpe.resultType) - ctx1 - } - genLoadApply4 - - case Apply(fun @ _, List(expr)) if (currentRun.runDefinitions.isUnbox(fun.symbol)) => - debuglog("UNBOX : " + fun.symbol.fullName) - val ctx1 = genLoad(expr, ctx, toTypeKind(expr.tpe)) - val boxType = toTypeKind(fun.symbol.owner.linkedClassOfClass.tpe) - generatedType = boxType - ctx1.bb.emit(UNBOX(boxType), expr.pos) - ctx1 - - case app @ Apply(fun, args) => - def genLoadApply6 = { - val sym = fun.symbol - - if (sym.isLabel) { // jump to a label - val label = ctx.labels.getOrElse(sym, { - // it is a forward jump, scan for labels - resolveForwardLabel(ctx.defdef, ctx, sym) - ctx.labels.get(sym) match { - case Some(l) => - debuglog("Forward jump for " + sym.fullLocationString + ": scan found label " + l) - l - case _ => - abort("Unknown label target: " + sym + " at: " + (fun.pos) + ": ctx: " + ctx) - } - }) - // note: when one of the args to genLoadLabelArguments is a jump to a label, - // it will call back into genLoad and arrive at this case, which will then set ctx1.bb.ignore to true, - // this is okay, since we're jumping unconditionally, so the loads and jumps emitted by the outer - // call to genLoad (by calling genLoadLabelArguments and emitOnly) can safely be ignored, - // however, as emitOnly will close the block, which reverses its instructions (when it's still open), - // we better not reverse when the block has already been closed but is in ignore mode - // (if it's not in ignore mode, double-closing is an error) - val ctx1 = genLoadLabelArguments(args, label, ctx) - ctx1.bb.emitOnly(if (label.anchored) JUMP(label.block) else PJUMP(label)) - ctx1.bb.enterIgnoreMode() - ctx1 - } else if (isPrimitive(sym)) { // primitive method call - val (newCtx, resKind) = genPrimitiveOp(app, ctx, expectedType) - generatedType = resKind - newCtx - } else { // normal method call - debuglog("Gen CALL_METHOD with sym: " + sym + " isStaticSymbol: " + sym.isStaticMember) - val invokeStyle = - if (sym.isStaticMember) - Static(onInstance = false) - else if (sym.isPrivate || sym.isClassConstructor) - Static(onInstance = true) - else - Dynamic - - var ctx1 = if (invokeStyle.hasInstance) genLoadQualifier(fun, ctx) else ctx - ctx1 = genLoadArguments(args, sym.info.paramTypes, ctx1) - val cm = CALL_METHOD(sym, invokeStyle) - - /* In a couple cases, squirrel away a little extra information in the - * CALL_METHOD for use by GenASM. - */ - fun match { - case Select(qual, _) => - val qualSym = findHostClass(qual.tpe, sym) - if (qualSym == ArrayClass) { - val kind = toTypeKind(qual.tpe) - cm setTargetTypeKind kind - log(s"Stored target type kind for {$sym.fullName} as $kind") - } - else { - cm setHostClass qualSym - if (qual.tpe.typeSymbol != qualSym) - log(s"Precisified host class for $sym from ${qual.tpe.typeSymbol.fullName} to ${qualSym.fullName}") - } - case _ => - } - ctx1.bb.emit(cm, tree.pos) - ctx1.method.updateRecursive(sym) - generatedType = - if (sym.isClassConstructor) UNIT - else toTypeKind(sym.info.resultType) - // deal with methods that return Null - adaptNullRef(generatedType, expectedType, ctx1, tree.pos) - ctx1 - } - } - genLoadApply6 - - case ApplyDynamic(qual, args) => - // TODO - this is where we'd catch dynamic applies for invokedynamic. - sys.error("No invokedynamic support yet.") - // val ctx1 = genLoad(qual, ctx, ObjectReference) - // genLoadArguments(args, tree.symbol.info.paramTypes, ctx1) - // ctx1.bb.emit(CALL_METHOD(tree.symbol, InvokeDynamic), tree.pos) - // ctx1 - - case This(qual) => - def genLoadThis = { - assert(tree.symbol == ctx.clazz.symbol || tree.symbol.isModuleClass, - "Trying to access the this of another class: " + - "tree.symbol = " + tree.symbol + ", ctx.clazz.symbol = " + ctx.clazz.symbol + " compilation unit:"+unit) - if (tree.symbol.isModuleClass && tree.symbol != ctx.clazz.symbol) { - genLoadModule(ctx, tree) - generatedType = REFERENCE(tree.symbol) - } else { - ctx.bb.emit(THIS(ctx.clazz.symbol), tree.pos) - generatedType = REFERENCE( - if (tree.symbol == ArrayClass) ObjectClass else ctx.clazz.symbol - ) - } - ctx - } - genLoadThis - - case Select(Ident(nme.EMPTY_PACKAGE_NAME), module) => - debugassert(tree.symbol.isModule, - "Selection of non-module from empty package: " + tree + - " sym: " + tree.symbol + " at: " + (tree.pos) - ) - genLoadModule(ctx, tree) - - case Select(qualifier, selector) => - def genLoadSelect = { - val sym = tree.symbol - generatedType = toTypeKind(sym.info) - val hostClass = findHostClass(qualifier.tpe, sym) - debuglog(s"Host class of $sym with qual $qualifier (${qualifier.tpe}) is $hostClass") - val qualSafeToElide = treeInfo isQualifierSafeToElide qualifier - - def genLoadQualUnlessElidable: Context = - if (qualSafeToElide) ctx else genLoadQualifier(tree, ctx) - - if (sym.isModule) { - genLoadModule(genLoadQualUnlessElidable, tree) - } else { - val isStatic = sym.isStaticMember - val ctx1 = if (isStatic) genLoadQualUnlessElidable - else genLoadQualifier(tree, ctx) - ctx1.bb.emit(LOAD_FIELD(sym, isStatic) setHostClass hostClass, tree.pos) - // it's tempting to drop field accesses of type Null instead of adapting them, - // but field access can cause static class init so we can't. Besides, fields - // of type Null probably aren't common enough to figure out an optimization - adaptNullRef(generatedType, expectedType, ctx1, tree.pos) - ctx1 - } - } - genLoadSelect - - case Ident(name) => - def genLoadIdent = { - val sym = tree.symbol - if (!sym.hasPackageFlag) { - if (sym.isModule) { - genLoadModule(ctx, tree) - generatedType = toTypeKind(sym.info) - } else { - ctx.method.lookupLocal(sym) match { - case Some(l) => - ctx.bb.emit(LOAD_LOCAL(l), tree.pos) - generatedType = l.kind - case None => - val saved = settings.uniqid - settings.uniqid.value = true - try { - val methodCode = unit.body.collect { case dd: DefDef - if dd.symbol == ctx.method.symbol => showCode(dd); - }.headOption.getOrElse("<unknown>") - abort(s"symbol $sym does not exist in ${ctx.method}, which contains locals ${ctx.method.locals.mkString(",")}. \nMethod code: $methodCode") - } - finally settings.uniqid.value = saved - } - } - } - ctx - } - genLoadIdent - - case Literal(value) => - def genLoadLiteral = { - if (value.tag != UnitTag) (value.tag, expectedType) match { - case (IntTag, LONG) => - ctx.bb.emit(CONSTANT(Constant(value.longValue)), tree.pos) - generatedType = LONG - case (FloatTag, DOUBLE) => - ctx.bb.emit(CONSTANT(Constant(value.doubleValue)), tree.pos) - generatedType = DOUBLE - case (NullTag, _) => - ctx.bb.emit(CONSTANT(value), tree.pos) - generatedType = NullReference - case _ => - ctx.bb.emit(CONSTANT(value), tree.pos) - generatedType = toTypeKind(tree.tpe) - } - ctx - } - genLoadLiteral - - case Block(stats, expr) => - ctx.enterScope() - var ctx1 = genStat(stats, ctx) - ctx1 = genLoad(expr, ctx1, expectedType) - ctx1.exitScope() - ctx1 - - case Typed(Super(_, _), _) => - genLoad(This(ctx.clazz.symbol), ctx, expectedType) - - case Typed(expr, _) => - genLoad(expr, ctx, expectedType) - - case Assign(_, _) => - generatedType = UNIT - genStat(tree, ctx) - - case ArrayValue(tpt @ TypeTree(), _elems) => - def genLoadArrayValue = { - var ctx1 = ctx - val elmKind = toTypeKind(tpt.tpe) - generatedType = ARRAY(elmKind) - val elems = _elems.toIndexedSeq - - ctx1.bb.emit(CONSTANT(new Constant(elems.length)), tree.pos) - ctx1.bb.emit(CREATE_ARRAY(elmKind, 1)) - // inline array literals - var i = 0 - while (i < elems.length) { - ctx1.bb.emit(DUP(generatedType), tree.pos) - ctx1.bb.emit(CONSTANT(new Constant(i))) - ctx1 = genLoad(elems(i), ctx1, elmKind) - ctx1.bb.emit(STORE_ARRAY_ITEM(elmKind)) - i = i + 1 - } - ctx1 - } - genLoadArrayValue - - case Match(selector, cases) => - def genLoadMatch = { - debuglog("Generating SWITCH statement.") - val ctx1 = genLoad(selector, ctx, INT) // TODO: Java 7 allows strings in switches (so, don't assume INT and don't convert the literals using intValue) - val afterCtx = ctx1.newBlock() - afterCtx.bb killIf ctx1.bb.ignore - var afterCtxReachable = false - var caseCtx: Context = null - generatedType = toTypeKind(tree.tpe) - - var targets: List[BasicBlock] = Nil - var tags: List[Int] = Nil - var default: BasicBlock = afterCtx.bb - - for (caze @ CaseDef(pat, guard, body) <- cases) { - assert(guard == EmptyTree, guard) - val tmpCtx = ctx1.newBlock() - tmpCtx.bb killIf ctx1.bb.ignore - pat match { - case Literal(value) => - tags = value.intValue :: tags - targets = tmpCtx.bb :: targets - case Ident(nme.WILDCARD) => - default = tmpCtx.bb - case Alternative(alts) => - alts foreach { - case Literal(value) => - tags = value.intValue :: tags - targets = tmpCtx.bb :: targets - case _ => - abort("Invalid case in alternative in switch-like pattern match: " + - tree + " at: " + tree.pos) - } - case _ => - abort("Invalid case statement in switch-like pattern match: " + - tree + " at: " + (tree.pos)) - } - - caseCtx = genLoad(body, tmpCtx, generatedType) - afterCtxReachable ||= !caseCtx.bb.ignore - // close the block unless it's already been closed by the body, which closes the block if it ends in a jump (which is emitted to have alternatives share their body) - caseCtx.bb.closeWith(JUMP(afterCtx.bb) setPos caze.pos) - } - afterCtxReachable ||= (default == afterCtx) - ctx1.bb.emitOnly( - SWITCH(tags.reverse map (x => List(x)), (default :: targets).reverse) setPos tree.pos - ) - afterCtx.bb killUnless afterCtxReachable - afterCtx - } - genLoadMatch - - case EmptyTree => - if (expectedType != UNIT) - ctx.bb.emit(getZeroOf(expectedType)) - ctx - - case _ => - abort("Unexpected tree in genLoad: " + tree + "/" + tree.getClass + " at: " + tree.pos) - } - - // emit conversion - if (generatedType != expectedType) { - tree match { - case Literal(Constant(null)) if generatedType == NullReference && expectedType != UNIT => - // literal null on the stack (as opposed to a boxed null, see SI-8233), - // we can bypass `adapt` which would otherwise emit a redundant [DROP, CONSTANT(null)] - // except one case: when expected type is UNIT (unboxed) where we need to emit just a DROP - case _ => - adapt(generatedType, expectedType, resCtx, tree.pos) - } - } - - resCtx - } - - /** - * If we have a method call, field load, or array element load of type Null then - * we need to convince the JVM that we have a null value because in Scala - * land Null is a subtype of all ref types, but in JVM land scala.runtime.Null$ - * is not. Note we don't have to adapt loads of locals because the JVM type - * system for locals does have a null type which it tracks internally. As - * long as we adapt these other things, the JVM will know that a Scala local of - * type Null is holding a null. - */ - private def adaptNullRef(from: TypeKind, to: TypeKind, ctx: Context, pos: Position) { - debuglog(s"GenICode#adaptNullRef($from, $to, $ctx, $pos)") - - // Don't need to adapt null to unit because we'll just drop it anyway. Don't - // need to adapt to Object or AnyRef because the JVM is happy with - // upcasting Null to them. - // We do have to adapt from NullReference to NullReference because we could be storing - // this value into a local of type Null and we want the JVM to see that it's - // a null value so we don't have to also adapt local loads. - if (from == NullReference && to != UNIT && to != ObjectReference && to != AnyRefReference) { - assert(to.isRefOrArrayType, s"Attempt to adapt a null to a non reference type $to.") - // adapt by dropping what we've got and pushing a null which - // will convince the JVM we really do have null - ctx.bb.emit(DROP(from), pos) - ctx.bb.emit(CONSTANT(Constant(null)), pos) - } - } - - private def adapt(from: TypeKind, to: TypeKind, ctx: Context, pos: Position) { - // An awful lot of bugs explode here - let's leave ourselves more clues. - // A typical example is an overloaded type assigned after typer. - debuglog(s"GenICode#adapt($from, $to, $ctx, $pos)") - - def coerce(from: TypeKind, to: TypeKind) = ctx.bb.emit(CALL_PRIMITIVE(Conversion(from, to)), pos) - - (from, to) match { - // The JVM doesn't have a Nothing equivalent, so it doesn't know that a method of type Nothing can't actually return. So for instance, with - // def f: String = ??? - // we need - // 0: getstatic #25; //Field scala/Predef$.MODULE$:Lscala/Predef$; - // 3: invokevirtual #29; //Method scala/Predef$.$qmark$qmark$qmark:()Lscala/runtime/Nothing$; - // 6: athrow - // So this case tacks on the ahtrow which makes the JVM happy because class Nothing is declared as a subclass of Throwable - case (NothingReference, _) => - ctx.bb.emit(THROW(ThrowableClass)) - ctx.bb.enterIgnoreMode() - case (NullReference, REFERENCE(_)) => - // SI-8223 we can't assume that the stack contains a `null`, it might contain a Null$ - ctx.bb.emit(Seq(DROP(from), CONSTANT(Constant(null)))) - case _ if from isAssignabledTo to => - () - case (_, UNIT) => - ctx.bb.emit(DROP(from), pos) - // otherwise we'd better be doing a primitive -> primitive coercion or there's a problem - case _ if !from.isRefOrArrayType && !to.isRefOrArrayType => - coerce(from, to) - case _ => - assert(false, s"Can't convert from $from to $to in unit ${unit.source} at $pos") - } - } - - /** Load the qualifier of `tree` on top of the stack. */ - private def genLoadQualifier(tree: Tree, ctx: Context): Context = - tree match { - case Select(qualifier, _) => - genLoad(qualifier, ctx, toTypeKind(qualifier.tpe)) - case _ => - abort("Unknown qualifier " + tree) - } - - /** - * Generate code that loads args into label parameters. - */ - private def genLoadLabelArguments(args: List[Tree], label: Label, ctx: Context): Context = { - debugassert( - args.length == label.params.length, - "Wrong number of arguments in call to label " + label.symbol - ) - var ctx1 = ctx - - def isTrivial(kv: (Tree, Symbol)) = kv match { - case (This(_), p) if p.name == nme.THIS => true - case (arg @ Ident(_), p) if arg.symbol == p => true - case _ => false - } - - val stores = args zip label.params filterNot isTrivial map { - case (arg, param) => - val local = ctx.method.lookupLocal(param).get - ctx1 = genLoad(arg, ctx1, local.kind) - - val store = - if (param.name == nme.THIS) STORE_THIS(toTypeKind(ctx1.clazz.symbol.tpe)) - else STORE_LOCAL(local) - - store setPos arg.pos - } - - // store arguments in reverse order on the stack - ctx1.bb.emit(stores.reverse) - ctx1 - } - - private def genLoadArguments(args: List[Tree], tpes: List[Type], ctx: Context): Context = - (args zip tpes).foldLeft(ctx) { - case (res, (arg, tpe)) => - genLoad(arg, res, toTypeKind(tpe)) - } - - private def genLoadModule(ctx: Context, tree: Tree): Context = { - // Working around SI-5604. Rather than failing the compile when we see - // a package here, check if there's a package object. - val sym = ( - if (!tree.symbol.isPackageClass) tree.symbol - else tree.symbol.info.member(nme.PACKAGE) match { - case NoSymbol => abort("Cannot use package as value: " + tree) - case s => - devWarning(s"Found ${tree.symbol} where a package object is required. Converting to ${s.moduleClass}") - s.moduleClass - } - ) - debuglog("LOAD_MODULE from %s: %s".format(tree.shortClass, sym)) - ctx.bb.emit(LOAD_MODULE(sym), tree.pos) - ctx - } - - def genConversion(from: TypeKind, to: TypeKind, ctx: Context, cast: Boolean) = { - if (cast) - ctx.bb.emit(CALL_PRIMITIVE(Conversion(from, to))) - else { - ctx.bb.emit(DROP(from)) - ctx.bb.emit(CONSTANT(Constant(from == to))) - } - } - - def genCast(from: TypeKind, to: TypeKind, ctx: Context, cast: Boolean) = - ctx.bb.emit(if (cast) CHECK_CAST(to) else IS_INSTANCE(to)) - - def getZeroOf(k: TypeKind): Instruction = k match { - case UNIT => CONSTANT(Constant(())) - case BOOL => CONSTANT(Constant(false)) - case BYTE => CONSTANT(Constant(0: Byte)) - case SHORT => CONSTANT(Constant(0: Short)) - case CHAR => CONSTANT(Constant(0: Char)) - case INT => CONSTANT(Constant(0: Int)) - case LONG => CONSTANT(Constant(0: Long)) - case FLOAT => CONSTANT(Constant(0.0f)) - case DOUBLE => CONSTANT(Constant(0.0d)) - case REFERENCE(cls) => CONSTANT(Constant(null: Any)) - case ARRAY(elem) => CONSTANT(Constant(null: Any)) - case BOXED(_) => CONSTANT(Constant(null: Any)) - case ConcatClass => abort("no zero of ConcatClass") - } - - - /** Is the given symbol a primitive operation? */ - def isPrimitive(fun: Symbol): Boolean = scalaPrimitives.isPrimitive(fun) - - /** Generate coercion denoted by "code" - */ - def genCoercion(tree: Tree, ctx: Context, code: Int) = { - import scalaPrimitives._ - (code: @switch) match { - case B2B => () - case B2C => ctx.bb.emit(CALL_PRIMITIVE(Conversion(BYTE, CHAR)), tree.pos) - case B2S => ctx.bb.emit(CALL_PRIMITIVE(Conversion(BYTE, SHORT)), tree.pos) - case B2I => ctx.bb.emit(CALL_PRIMITIVE(Conversion(BYTE, INT)), tree.pos) - case B2L => ctx.bb.emit(CALL_PRIMITIVE(Conversion(BYTE, LONG)), tree.pos) - case B2F => ctx.bb.emit(CALL_PRIMITIVE(Conversion(BYTE, FLOAT)), tree.pos) - case B2D => ctx.bb.emit(CALL_PRIMITIVE(Conversion(BYTE, DOUBLE)), tree.pos) - - case S2B => ctx.bb.emit(CALL_PRIMITIVE(Conversion(SHORT, BYTE)), tree.pos) - case S2S => () - case S2C => ctx.bb.emit(CALL_PRIMITIVE(Conversion(SHORT, CHAR)), tree.pos) - case S2I => ctx.bb.emit(CALL_PRIMITIVE(Conversion(SHORT, INT)), tree.pos) - case S2L => ctx.bb.emit(CALL_PRIMITIVE(Conversion(SHORT, LONG)), tree.pos) - case S2F => ctx.bb.emit(CALL_PRIMITIVE(Conversion(SHORT, FLOAT)), tree.pos) - case S2D => ctx.bb.emit(CALL_PRIMITIVE(Conversion(SHORT, DOUBLE)), tree.pos) - - case C2B => ctx.bb.emit(CALL_PRIMITIVE(Conversion(CHAR, BYTE)), tree.pos) - case C2S => ctx.bb.emit(CALL_PRIMITIVE(Conversion(CHAR, SHORT)), tree.pos) - case C2C => () - case C2I => ctx.bb.emit(CALL_PRIMITIVE(Conversion(CHAR, INT)), tree.pos) - case C2L => ctx.bb.emit(CALL_PRIMITIVE(Conversion(CHAR, LONG)), tree.pos) - case C2F => ctx.bb.emit(CALL_PRIMITIVE(Conversion(CHAR, FLOAT)), tree.pos) - case C2D => ctx.bb.emit(CALL_PRIMITIVE(Conversion(CHAR, DOUBLE)), tree.pos) - - case I2B => ctx.bb.emit(CALL_PRIMITIVE(Conversion(INT, BYTE)), tree.pos) - case I2S => ctx.bb.emit(CALL_PRIMITIVE(Conversion(INT, SHORT)), tree.pos) - case I2C => ctx.bb.emit(CALL_PRIMITIVE(Conversion(INT, CHAR)), tree.pos) - case I2I => () - case I2L => ctx.bb.emit(CALL_PRIMITIVE(Conversion(INT, LONG)), tree.pos) - case I2F => ctx.bb.emit(CALL_PRIMITIVE(Conversion(INT, FLOAT)), tree.pos) - case I2D => ctx.bb.emit(CALL_PRIMITIVE(Conversion(INT, DOUBLE)), tree.pos) - - case L2B => ctx.bb.emit(CALL_PRIMITIVE(Conversion(LONG, BYTE)), tree.pos) - case L2S => ctx.bb.emit(CALL_PRIMITIVE(Conversion(LONG, SHORT)), tree.pos) - case L2C => ctx.bb.emit(CALL_PRIMITIVE(Conversion(LONG, CHAR)), tree.pos) - case L2I => ctx.bb.emit(CALL_PRIMITIVE(Conversion(LONG, INT)), tree.pos) - case L2L => () - case L2F => ctx.bb.emit(CALL_PRIMITIVE(Conversion(LONG, FLOAT)), tree.pos) - case L2D => ctx.bb.emit(CALL_PRIMITIVE(Conversion(LONG, DOUBLE)), tree.pos) - - case F2B => ctx.bb.emit(CALL_PRIMITIVE(Conversion(FLOAT, BYTE)), tree.pos) - case F2S => ctx.bb.emit(CALL_PRIMITIVE(Conversion(FLOAT, SHORT)), tree.pos) - case F2C => ctx.bb.emit(CALL_PRIMITIVE(Conversion(FLOAT, CHAR)), tree.pos) - case F2I => ctx.bb.emit(CALL_PRIMITIVE(Conversion(FLOAT, INT)), tree.pos) - case F2L => ctx.bb.emit(CALL_PRIMITIVE(Conversion(FLOAT, LONG)), tree.pos) - case F2F => () - case F2D => ctx.bb.emit(CALL_PRIMITIVE(Conversion(FLOAT, DOUBLE)), tree.pos) - - case D2B => ctx.bb.emit(CALL_PRIMITIVE(Conversion(DOUBLE, BYTE)), tree.pos) - case D2S => ctx.bb.emit(CALL_PRIMITIVE(Conversion(DOUBLE, SHORT)), tree.pos) - case D2C => ctx.bb.emit(CALL_PRIMITIVE(Conversion(DOUBLE, CHAR)), tree.pos) - case D2I => ctx.bb.emit(CALL_PRIMITIVE(Conversion(DOUBLE, INT)), tree.pos) - case D2L => ctx.bb.emit(CALL_PRIMITIVE(Conversion(DOUBLE, LONG)), tree.pos) - case D2F => ctx.bb.emit(CALL_PRIMITIVE(Conversion(DOUBLE, FLOAT)), tree.pos) - case D2D => () - - case _ => abort("Unknown coercion primitive: " + code) - } - } - - /** The Object => String overload. - */ - private lazy val String_valueOf: Symbol = getMember(StringModule, nme.valueOf) filter (sym => - sym.info.paramTypes match { - case List(pt) => pt.typeSymbol == ObjectClass - case _ => false - } - ) - - // I wrote it this way before I realized all the primitive types are - // boxed at this point, so I'd have to unbox them. Keeping it around in - // case we want to get more precise. - // - // private def valueOfForType(tp: Type): Symbol = { - // val xs = getMember(StringModule, nme.valueOf) filter (sym => - // // We always exclude the Array[Char] overload because java throws an NPE if - // // you pass it a null. It will instead find the Object one, which doesn't. - // sym.info.paramTypes match { - // case List(pt) => pt.typeSymbol != ArrayClass && (tp <:< pt) - // case _ => false - // } - // ) - // xs.alternatives match { - // case List(sym) => sym - // case _ => NoSymbol - // } - // } - - /** Generate string concatenation. - */ - def genStringConcat(tree: Tree, ctx: Context): Context = { - liftStringConcat(tree) match { - // Optimization for expressions of the form "" + x. We can avoid the StringBuilder. - case List(Literal(Constant("")), arg) => - debuglog("Rewriting \"\" + x as String.valueOf(x) for: " + arg) - val ctx1 = genLoad(arg, ctx, ObjectReference) - ctx1.bb.emit(CALL_METHOD(String_valueOf, Static(onInstance = false)), arg.pos) - ctx1 - case concatenations => - debuglog("Lifted string concatenations for " + tree + "\n to: " + concatenations) - var ctx1 = ctx - ctx1.bb.emit(CALL_PRIMITIVE(StartConcat), tree.pos) - for (elem <- concatenations) { - val kind = toTypeKind(elem.tpe) - ctx1 = genLoad(elem, ctx1, kind) - ctx1.bb.emit(CALL_PRIMITIVE(StringConcat(kind)), elem.pos) - } - ctx1.bb.emit(CALL_PRIMITIVE(EndConcat), tree.pos) - ctx1 - } - } - - /** Generate the scala ## method. - */ - def genScalaHash(tree: Tree, ctx: Context): Context = { - val hashMethod = { - ctx.bb.emit(LOAD_MODULE(ScalaRunTimeModule)) - getMember(ScalaRunTimeModule, nme.hash_) - } - - val ctx1 = genLoad(tree, ctx, ObjectReference) - ctx1.bb.emit(CALL_METHOD(hashMethod, Static(onInstance = false))) - ctx1 - } - - /** - * Returns a list of trees that each should be concatenated, from - * left to right. It turns a chained call like "a".+("b").+("c") into - * a list of arguments. - */ - def liftStringConcat(tree: Tree): List[Tree] = tree match { - case Apply(fun @ Select(larg, method), rarg) => - if (isPrimitive(fun.symbol) && - scalaPrimitives.getPrimitive(fun.symbol) == scalaPrimitives.CONCAT) - liftStringConcat(larg) ::: rarg - else - List(tree) - case _ => - List(tree) - } - - /** - * Find the label denoted by `lsym` and enter it in context `ctx`. - * - * We only enter one symbol at a time, even though we might traverse the same - * tree more than once per method. That's because we cannot enter labels that - * might be duplicated (for instance, inside finally blocks). - * - * TODO: restrict the scanning to smaller subtrees than the whole method. - * It is sufficient to scan the trees of the innermost enclosing block. - */ - private def resolveForwardLabel(tree: Tree, ctx: Context, lsym: Symbol): Unit = tree foreachPartial { - case t @ LabelDef(_, params, rhs) if t.symbol == lsym => - ctx.labels.getOrElseUpdate(t.symbol, { - val locals = params map (p => new Local(p.symbol, toTypeKind(p.symbol.info), false)) - ctx.method addLocals locals - - new Label(t.symbol) setParams (params map (_.symbol)) - }) - rhs - } - - /** - * Generate code for conditional expressions. The two basic blocks - * represent the continuation in case of success/failure of the - * test. - */ - private def genCond(tree: Tree, - ctx: Context, - thenCtx: Context, - elseCtx: Context): Boolean = - { - /** - * Generate the de-sugared comparison mechanism that will underly an '==' - * - * @param l left-hand side of the '==' - * @param r right-hand side of the '==' - * @param code the comparison operator to use - * @return true if either branch can continue normally to a follow on block, false otherwise - */ - def genComparisonOp(l: Tree, r: Tree, code: Int): Boolean = { - val op: TestOp = code match { - case scalaPrimitives.LT => LT - case scalaPrimitives.LE => LE - case scalaPrimitives.GT => GT - case scalaPrimitives.GE => GE - case scalaPrimitives.ID | scalaPrimitives.EQ => EQ - case scalaPrimitives.NI | scalaPrimitives.NE => NE - - case _ => abort("Unknown comparison primitive: " + code) - } - - // special-case reference (in)equality test for null (null eq x, x eq null) - lazy val nonNullSide = ifOneIsNull(l, r) - if (isReferenceEqualityOp(code) && nonNullSide != null) { - val ctx1 = genLoad(nonNullSide, ctx, ObjectReference) - val branchesReachable = !ctx1.bb.ignore - ctx1.bb.emitOnly( - CZJUMP(thenCtx.bb, elseCtx.bb, op, ObjectReference) - ) - branchesReachable - } - else { - val kind = getMaxType(l.tpe :: r.tpe :: Nil) - var ctx1 = genLoad(l, ctx, kind) - ctx1 = genLoad(r, ctx1, kind) - val branchesReachable = !ctx1.bb.ignore - - ctx1.bb.emitOnly( - CJUMP(thenCtx.bb, elseCtx.bb, op, kind) setPos r.pos - ) - branchesReachable - } - } - - debuglog("Entering genCond with tree: " + tree) - - // the default emission - def default(): Boolean = { - val ctx1 = genLoad(tree, ctx, BOOL) - val branchesReachable = !ctx1.bb.ignore - ctx1.bb.closeWith(CZJUMP(thenCtx.bb, elseCtx.bb, NE, BOOL) setPos tree.pos) - branchesReachable - } - - tree match { - // The comparison symbol is in ScalaPrimitives's "primitives" map - case Apply(fun, args) if isPrimitive(fun.symbol) => - import scalaPrimitives.{ ZNOT, ZAND, ZOR, EQ, getPrimitive } - - // lhs and rhs of test - lazy val Select(lhs, _) = fun - lazy val rhs = args.head - - def genZandOrZor(and: Boolean): Boolean = { - val ctxInterm = ctx.newBlock() - - val lhsBranchesReachable = if (and) genCond(lhs, ctx, ctxInterm, elseCtx) - else genCond(lhs, ctx, thenCtx, ctxInterm) - // If lhs is known to throw, we can kill the just created ctxInterm. - ctxInterm.bb killUnless lhsBranchesReachable - - val rhsBranchesReachable = genCond(rhs, ctxInterm, thenCtx, elseCtx) - - // Reachable means "it does not always throw", i.e. "it might not throw". - // In an expression (a && b) or (a || b), the b branch might not be evaluated. - // Such an expression is therefore known to throw only if both expressions throw. Or, - // successors are reachable if either of the two is reachable (SI-8625). - lhsBranchesReachable || rhsBranchesReachable - } - def genRefEq(isEq: Boolean) = { - val f = genEqEqPrimitive(lhs, rhs, ctx) _ - if (isEq) f(thenCtx, elseCtx) - else f(elseCtx, thenCtx) - } - - getPrimitive(fun.symbol) match { - case ZNOT => genCond(lhs, ctx, elseCtx, thenCtx) - case ZAND => genZandOrZor(and = true) - case ZOR => genZandOrZor(and = false) - case code => - // x == y where LHS is reference type - if (isUniversalEqualityOp(code) && toTypeKind(lhs.tpe).isReferenceType) { - if (code == EQ) genRefEq(isEq = true) - else genRefEq(isEq = false) - } - else if (isComparisonOp(code)) - genComparisonOp(lhs, rhs, code) - else - default() - } - - case _ => default() - } - } - - /** - * Generate the "==" code for object references. It is equivalent of - * if (l eq null) r eq null else l.equals(r); - * - * @param l left-hand side of the '==' - * @param r right-hand side of the '==' - * @param ctx current context - * @param thenCtx target context if the comparison yields true - * @param elseCtx target context if the comparison yields false - * @return true if either branch can continue normally to a follow on block, false otherwise - */ - def genEqEqPrimitive(l: Tree, r: Tree, ctx: Context)(thenCtx: Context, elseCtx: Context): Boolean = { - def getTempLocal = ctx.method.lookupLocal(nme.EQEQ_LOCAL_VAR) getOrElse { - ctx.makeLocal(l.pos, AnyRefTpe, nme.EQEQ_LOCAL_VAR.toString) - } - - /* True if the equality comparison is between values that require the use of the rich equality - * comparator (scala.runtime.Comparator.equals). This is the case when either side of the - * comparison might have a run-time type subtype of java.lang.Number or java.lang.Character. - * When it is statically known that both sides are equal and subtypes of Number of Character, - * not using the rich equality is possible (their own equals method will do ok.)*/ - def mustUseAnyComparator: Boolean = { - def areSameFinals = l.tpe.isFinalType && r.tpe.isFinalType && (l.tpe =:= r.tpe) - !areSameFinals && isMaybeBoxed(l.tpe.typeSymbol) && isMaybeBoxed(r.tpe.typeSymbol) - } - - if (mustUseAnyComparator) { - // when -optimise is on we call the @inline-version of equals, found in ScalaRunTime - val equalsMethod: Symbol = { - if (!settings.optimise) { - if (l.tpe <:< BoxedNumberClass.tpe) { - if (r.tpe <:< BoxedNumberClass.tpe) platform.externalEqualsNumNum - else if (r.tpe <:< BoxedCharacterClass.tpe) platform.externalEqualsNumObject // will be externalEqualsNumChar in 2.12, SI-9030 - else platform.externalEqualsNumObject - } else platform.externalEquals - } else { - ctx.bb.emit(LOAD_MODULE(ScalaRunTimeModule)) - getMember(ScalaRunTimeModule, nme.inlinedEquals) - } - } - - val ctx1 = genLoad(l, ctx, ObjectReference) - val ctx2 = genLoad(r, ctx1, ObjectReference) - val branchesReachable = !ctx2.bb.ignore - ctx2.bb.emitOnly( - CALL_METHOD(equalsMethod, if (settings.optimise) Dynamic else Static(onInstance = false)), - CZJUMP(thenCtx.bb, elseCtx.bb, NE, BOOL) - ) - branchesReachable - } - else { - if (isNull(l)) { - // null == expr -> expr eq null - val ctx1 = genLoad(r, ctx, ObjectReference) - val branchesReachable = !ctx1.bb.ignore - ctx1.bb emitOnly CZJUMP(thenCtx.bb, elseCtx.bb, EQ, ObjectReference) - branchesReachable - } else if (isNull(r)) { - // expr == null -> expr eq null - val ctx1 = genLoad(l, ctx, ObjectReference) - val branchesReachable = !ctx1.bb.ignore - ctx1.bb emitOnly CZJUMP(thenCtx.bb, elseCtx.bb, EQ, ObjectReference) - branchesReachable - } else if (isNonNullExpr(l)) { - // Avoid null check if L is statically non-null. - // - // "" == expr -> "".equals(expr) - // Nil == expr -> Nil.equals(expr) - // - // Common enough (through pattern matching) to treat this specially here rather than - // hoping that -Yconst-opt is enabled. The impossible branches for null checks lead - // to spurious "branch not covered" warnings in Jacoco code coverage. - var ctx1 = genLoad(l, ctx, ObjectReference) - val branchesReachable = !ctx1.bb.ignore - ctx1 = genLoad(r, ctx1, ObjectReference) - ctx1.bb emitOnly( - CALL_METHOD(Object_equals, Dynamic), - CZJUMP(thenCtx.bb, elseCtx.bb, NE, BOOL) - ) - branchesReachable - } else { - val eqEqTempLocal = getTempLocal - var ctx1 = genLoad(l, ctx, ObjectReference) - val branchesReachable = !ctx1.bb.ignore - lazy val nonNullCtx = { - val block = ctx1.newBlock() - block.bb killUnless branchesReachable - block - } - - // l == r -> if (l eq null) r eq null else l.equals(r) - ctx1 = genLoad(r, ctx1, ObjectReference) - val nullCtx = ctx1.newBlock() - nullCtx.bb killUnless branchesReachable - - ctx1.bb.emitOnly( - STORE_LOCAL(eqEqTempLocal) setPos l.pos, - DUP(ObjectReference), - CZJUMP(nullCtx.bb, nonNullCtx.bb, EQ, ObjectReference) - ) - nullCtx.bb.emitOnly( - DROP(ObjectReference) setPos l.pos, // type of AnyRef - LOAD_LOCAL(eqEqTempLocal), - CZJUMP(thenCtx.bb, elseCtx.bb, EQ, ObjectReference) - ) - nonNullCtx.bb.emitOnly( - LOAD_LOCAL(eqEqTempLocal) setPos l.pos, - CALL_METHOD(Object_equals, Dynamic), - CZJUMP(thenCtx.bb, elseCtx.bb, NE, BOOL) - ) - branchesReachable - } - } - } - - /** - * Add all fields of the given class symbol to the current ICode - * class. - */ - private def addClassFields(ctx: Context, cls: Symbol) { - debugassert(ctx.clazz.symbol eq cls, - "Classes are not the same: " + ctx.clazz.symbol + ", " + cls) - - /* Non-method term members are fields, except for module members. Module - * members can only happen on .NET (no flatten) for inner traits. There, - * a module symbol is generated (transformInfo in mixin) which is used - * as owner for the members of the implementation class (so that the - * backend emits them as static). - * No code is needed for this module symbol. - */ - for (f <- cls.info.decls ; if !f.isMethod && f.isTerm && !f.isModule) - ctx.clazz addField new IField(f) - } - - /** - * Add parameters to the current ICode method. It is assumed the methods - * have been uncurried, so the list of lists contains just one list. - */ - private def addMethodParams(ctx: Context, vparamss: List[List[ValDef]]) { - vparamss match { - case Nil => () - - case vparams :: Nil => - for (p <- vparams) { - val lv = new Local(p.symbol, toTypeKind(p.symbol.info), true) - ctx.method.addParam(lv) - ctx.scope.add(lv) - ctx.bb.varsInScope += lv - } - ctx.method.params = ctx.method.params.reverse - - case _ => - abort("Malformed parameter list: " + vparamss) - } - } - - /** Does this tree have a try-catch block? */ - def mayCleanStack(tree: Tree): Boolean = tree exists { - case Try(_, _, _) => true - case _ => false - } - - /** - * If the block consists of a single unconditional jump, prune - * it by replacing the instructions in the predecessor to jump - * directly to the JUMP target of the block. - */ - def prune(method: IMethod) = { - var changed = false - var n = 0 - - def prune0(block: BasicBlock): Unit = { - val optCont = block.lastInstruction match { - case JUMP(b) if (b != block) => Some(b) - case _ => None - } - if (block.size == 1 && optCont.isDefined) { - val Some(cont) = optCont - val pred = block.predecessors - debuglog("Preds: " + pred + " of " + block + " (" + optCont + ")") - pred foreach { p => - changed = true - p.lastInstruction match { - case CJUMP(succ, fail, cond, kind) if (succ == block || fail == block) => - debuglog("Pruning empty if branch.") - p.replaceInstruction(p.lastInstruction, - if (block == succ) - if (block == fail) - CJUMP(cont, cont, cond, kind) - else - CJUMP(cont, fail, cond, kind) - else if (block == fail) - CJUMP(succ, cont, cond, kind) - else - abort("Could not find block in preds: " + method + " " + block + " " + pred + " " + p)) - - case CZJUMP(succ, fail, cond, kind) if (succ == block || fail == block) => - debuglog("Pruning empty ifz branch.") - p.replaceInstruction(p.lastInstruction, - if (block == succ) - if (block == fail) - CZJUMP(cont, cont, cond, kind) - else - CZJUMP(cont, fail, cond, kind) - else if (block == fail) - CZJUMP(succ, cont, cond, kind) - else - abort("Could not find block in preds")) - - case JUMP(b) if (b == block) => - debuglog("Pruning empty JMP branch.") - val replaced = p.replaceInstruction(p.lastInstruction, JUMP(cont)) - debugassert(replaced, "Didn't find p.lastInstruction") - - case SWITCH(tags, labels) if (labels contains block) => - debuglog("Pruning empty SWITCH branch.") - p.replaceInstruction(p.lastInstruction, - SWITCH(tags, labels map (l => if (l == block) cont else l))) - - // the last instr of the predecessor `p` is not a jump to the block `block`. - // this happens when `block` is part of an exception handler covering `b`. - case _ => () - } - } - if (changed) { - debuglog("Removing block: " + block) - method.code.removeBlock(block) - for (e <- method.exh) { - e.covered = e.covered filter (_ != block) - e.blocks = e.blocks filter (_ != block) - if (e.startBlock eq block) - e setStartBlock cont - } - } - } - } - - do { - changed = false - n += 1 - method.blocks foreach prune0 - } while (changed) - - debuglog("Prune fixpoint reached in " + n + " iterations.") - } - - def getMaxType(ts: List[Type]): TypeKind = - ts map toTypeKind reduceLeft (_ maxType _) - - /** Tree transformer that duplicates code and at the same time creates - * fresh symbols for existing labels. Since labels may be used before - * they are defined (forward jumps), all labels found are mapped to fresh - * symbols. References to the same label (use or definition) will remain - * consistent after this transformation (both the use and the definition of - * some label l will be mapped to the same label l'). - * - * Note: If the tree fragment passed to the duplicator contains unbound - * label names, the bind to the outer labeldef will be lost! That's because - * a use of an unbound label l will be transformed to l', and the corresponding - * label def, being outside the scope of this transformation, will not be updated. - * - * All LabelDefs are entered into the context label map, since it makes no sense - * to delay it any more: they will be used at some point. - */ - class DuplicateLabels(boundLabels: Set[Symbol]) extends Transformer { - val labels = perRunCaches.newMap[Symbol, Symbol]() - var method: Symbol = _ - var ctx: Context = _ - - def apply(ctx: Context, t: Tree) = { - this.method = ctx.method.symbol - this.ctx = ctx - transform(t) - } - - override def transform(t: Tree): Tree = { - val sym = t.symbol - def getLabel(pos: Position, name: Name) = - labels.getOrElseUpdate(sym, - method.newLabel(unit.freshTermName(name.toString), sym.pos) setInfo sym.tpe - ) - - t match { - case t @ Apply(_, args) if sym.isLabel && !boundLabels(sym) => - val newSym = getLabel(sym.pos, sym.name) - Apply(global.gen.mkAttributedRef(newSym), transformTrees(args)) setPos t.pos setType t.tpe - - case t @ LabelDef(name, params, rhs) => - val newSym = getLabel(t.pos, name) - val tree = treeCopy.LabelDef(t, newSym.name, params, transform(rhs)) - tree.symbol = newSym - - val pair = (newSym -> (new Label(newSym) setParams (params map (_.symbol)))) - log("Added " + pair + " to labels.") - ctx.labels += pair - ctx.method.addLocals(params map (p => new Local(p.symbol, toTypeKind(p.symbol.info), false))) - - tree - - case _ => super.transform(t) - } - } - } - - /////////////////////// Context //////////////////////////////// - - sealed abstract class Cleanup(val value: AnyRef) { - def contains(x: AnyRef) = value == x - } - case class MonitorRelease(m: Local) extends Cleanup(m) { } - case class Finalizer(f: Tree, ctx: Context) extends Cleanup (f) { } - - def duplicateFinalizer(boundLabels: Set[Symbol], targetCtx: Context, finalizer: Tree) = { - (new DuplicateLabels(boundLabels))(targetCtx, finalizer) - } - - def savingCleanups[T](ctx: Context)(body: => T): T = { - val saved = ctx.cleanups - try body - finally ctx.cleanups = saved - } - - /** - * The Context class keeps information relative to the current state - * in code generation - */ - class Context { - /** The current package. */ - var packg: Name = _ - - /** The current class. */ - var clazz: IClass = _ - - /** The current method. */ - var method: IMethod = _ - - /** The current basic block. */ - var bb: BasicBlock = _ - - /** Map from label symbols to label objects. */ - var labels = perRunCaches.newMap[Symbol, Label]() - - /** Current method definition. */ - var defdef: DefDef = _ - - /** current exception handlers */ - var handlers: List[ExceptionHandler] = Nil - - /** The current monitors or finalizers, to be cleaned up upon `return`. */ - var cleanups: List[Cleanup] = Nil - - /** The exception handlers we are currently generating code for */ - var currentExceptionHandlers: List[ExceptionHandler] = Nil - - /** The current local variable scope. */ - var scope: Scope = EmptyScope - - var handlerCount = 0 - - override def toString = - s"package $packg { class $clazz { def $method { bb=$bb } } }" - - def loadException(ctx: Context, exh: ExceptionHandler, pos: Position) = { - debuglog("Emitting LOAD_EXCEPTION for class: " + exh.loadExceptionClass) - ctx.bb.emit(LOAD_EXCEPTION(exh.loadExceptionClass) setPos pos, pos) - } - - def this(other: Context) = { - this() - this.packg = other.packg - this.clazz = other.clazz - this.method = other.method - this.bb = other.bb - this.labels = other.labels - this.defdef = other.defdef - this.handlers = other.handlers - this.handlerCount = other.handlerCount - this.cleanups = other.cleanups - this.currentExceptionHandlers = other.currentExceptionHandlers - this.scope = other.scope - } - - def setPackage(p: Name): this.type = { - this.packg = p - this - } - - def setClass(c: IClass): this.type = { - this.clazz = c - this - } - - def setMethod(m: IMethod): this.type = { - this.method = m - this - } - - def setBasicBlock(b: BasicBlock): this.type = { - this.bb = b - this - } - - def enterSynchronized(monitor: Local): this.type = { - cleanups = MonitorRelease(monitor) :: cleanups - this - } - - def exitSynchronized(monitor: Local): this.type = { - assert(cleanups.head contains monitor, - "Bad nesting of cleanup operations: " + cleanups + " trying to exit from monitor: " + monitor) - cleanups = cleanups.tail - this - } - - def addFinalizer(f: Tree, ctx: Context): this.type = { - cleanups = Finalizer(f, ctx) :: cleanups - this - } - - /** Prepare a new context upon entry into a method. - */ - def enterMethod(m: IMethod, d: DefDef): Context = { - val ctx1 = new Context(this) setMethod(m) - ctx1.labels = mutable.HashMap() - ctx1.method.code = new Code(m) - ctx1.bb = ctx1.method.startBlock - ctx1.defdef = d - ctx1.scope = EmptyScope - ctx1.enterScope() - ctx1 - } - - /** Return a new context for a new basic block. */ - def newBlock(): Context = { - val block = method.code.newBlock() - handlers foreach (_ addCoveredBlock block) - currentExceptionHandlers foreach (_ addBlock block) - block.varsInScope.clear() - block.varsInScope ++= scope.varsInScope - new Context(this) setBasicBlock block - } - - def enterScope() { - scope = new Scope(scope) - } - - def exitScope() { - if (bb.nonEmpty) { - scope.locals foreach { lv => bb.emit(SCOPE_EXIT(lv)) } - } - scope = scope.outer - } - - /** Create a new exception handler and adds it in the list - * of current exception handlers. All new blocks will be - * 'covered' by this exception handler (in addition to the - * previously active handlers). - */ - private def newExceptionHandler(cls: Symbol, pos: Position): ExceptionHandler = { - handlerCount += 1 - val exh = new ExceptionHandler(method, newTermNameCached("" + handlerCount), cls, pos) - method.addHandler(exh) - handlers = exh :: handlers - debuglog("added handler: " + exh) - - exh - } - - /** Add an active exception handler in this context. It will cover all new basic blocks - * created from now on. */ - private def addActiveHandler(exh: ExceptionHandler) { - handlerCount += 1 - handlers = exh :: handlers - debuglog("added handler: " + exh) - } - - /** Return a new context for generating code for the given - * exception handler. - */ - private def enterExceptionHandler(exh: ExceptionHandler): Context = { - currentExceptionHandlers ::= exh - val ctx = newBlock() - exh.setStartBlock(ctx.bb) - ctx - } - - def endHandler() { - currentExceptionHandlers = currentExceptionHandlers.tail - } - - /** Clone the current context */ - def dup: Context = new Context(this) - - /** Make a fresh local variable. It ensures the 'name' is unique. */ - def makeLocal(pos: Position, tpe: Type, name: String): Local = { - val sym = method.symbol.newVariable(unit.freshTermName(name), pos, Flags.SYNTHETIC) setInfo tpe - this.method.addLocal(new Local(sym, toTypeKind(tpe), false)) - } - - - /** - * Generate exception handlers for the body. Body is evaluated - * with a context where all the handlers are active. Handlers are - * evaluated in the 'outer' context. - * - * It returns the resulting context, with the same active handlers as - * before the call. Use it like: - * - * ` ctx.Try( ctx => { - * ctx.bb.emit(...) // protected block - * }, (ThrowableClass, - * ctx => { - * ctx.bb.emit(...); // exception handler - * }), (AnotherExceptionClass, - * ctx => {... - * } ))` - * - * The resulting structure will look something like - * - * outer: - * // this 'useless' jump will be removed later, - * // for now it separates the try body's blocks from previous - * // code since the try body needs its own exception handlers - * JUMP body - * - * body: - * [ try body ] - * JUMP normalExit - * - * catch[i]: - * [ handler[i] body ] - * JUMP normalExit - * - * catchAll: - * STORE exception - * [ finally body ] - * THROW exception - * - * normalExit: - * [ finally body ] - * - * each catch[i] will cover body. catchAll will cover both body and each catch[i] - * Additional finally copies are created on the emission of every RETURN in the try body and exception handlers. - * - * This could result in unreachable code which has to be cleaned up later, e.g. if the try and all the exception - * handlers always end in RETURN then there will be no "normal" flow out of the try/catch/finally. - * Later reachability analysis will remove unreachable code. - */ - def Try(body: Context => Context, - handlers: List[(Symbol, TypeKind, Context => Context)], - finalizer: Tree, - tree: Tree) = { - - val outerCtx = this.dup // context for generating exception handlers, covered by the catch-all finalizer - val finalizerCtx = this.dup // context for generating finalizer handler - val normalExitCtx = outerCtx.newBlock() // context where flow will go on a "normal" (non-return, non-throw) exit from a try or catch handler - var normalExitReachable = false - var tmp: Local = null - val kind = toTypeKind(tree.tpe) - val guardResult = kind != UNIT && mayCleanStack(finalizer) - // we need to save bound labels before any code generation is performed on - // the current context (otherwise, any new labels in the finalizer that need to - // be duplicated would be incorrectly considered bound -- see #2850). - val boundLabels: Set[Symbol] = Set.empty ++ labels.keySet - - if (guardResult) { - tmp = this.makeLocal(tree.pos, tree.tpe, "tmp") - } - - def emitFinalizer(ctx: Context): Context = if (!finalizer.isEmpty) { - val ctx1 = finalizerCtx.dup.newBlock() - ctx1.bb killIf ctx.bb.ignore - ctx.bb.closeWith(JUMP(ctx1.bb)) - - if (guardResult) { - ctx1.bb.emit(STORE_LOCAL(tmp)) - val ctx2 = genLoad(duplicateFinalizer(boundLabels, ctx1, finalizer), ctx1, UNIT) - ctx2.bb.emit(LOAD_LOCAL(tmp)) - ctx2 - } else - genLoad(duplicateFinalizer(boundLabels, ctx1, finalizer), ctx1, UNIT) - } else ctx - - - // Generate the catch-all exception handler that deals with uncaught exceptions coming - // from the try or exception handlers. It catches the exception, runs the finally code, then rethrows - // the exception - if (settings.YdisableUnreachablePrevention || !outerCtx.bb.ignore) { - if (finalizer != EmptyTree) { - val exh = outerCtx.newExceptionHandler(NoSymbol, finalizer.pos) // finalizer covers exception handlers - this.addActiveHandler(exh) // .. and body as well - val exhStartCtx = finalizerCtx.enterExceptionHandler(exh) - exhStartCtx.bb killIf outerCtx.bb.ignore - val exception = exhStartCtx.makeLocal(finalizer.pos, ThrowableTpe, "exc") - loadException(exhStartCtx, exh, finalizer.pos) - exhStartCtx.bb.emit(STORE_LOCAL(exception)) - val exhEndCtx = genLoad(finalizer, exhStartCtx, UNIT) - exhEndCtx.bb.emit(LOAD_LOCAL(exception)) - exhEndCtx.bb.closeWith(THROW(ThrowableClass)) - exhEndCtx.bb.enterIgnoreMode() - finalizerCtx.endHandler() - } - - // Generate each exception handler - for ((sym, kind, handler) <- handlers) { - val exh = this.newExceptionHandler(sym, tree.pos) - val exhStartCtx = outerCtx.enterExceptionHandler(exh) - exhStartCtx.bb killIf outerCtx.bb.ignore - exhStartCtx.addFinalizer(finalizer, finalizerCtx) - loadException(exhStartCtx, exh, tree.pos) - val exhEndCtx = handler(exhStartCtx) - normalExitReachable ||= !exhEndCtx.bb.ignore - exhEndCtx.bb.closeWith(JUMP(normalExitCtx.bb)) - outerCtx.endHandler() - } - } - - val bodyCtx = this.newBlock() - bodyCtx.bb killIf outerCtx.bb.ignore - if (finalizer != EmptyTree) - bodyCtx.addFinalizer(finalizer, finalizerCtx) - - val bodyEndCtx = body(bodyCtx) - - outerCtx.bb.closeWith(JUMP(bodyCtx.bb)) - - normalExitReachable ||= !bodyEndCtx.bb.ignore - normalExitCtx.bb killUnless normalExitReachable - bodyEndCtx.bb.closeWith(JUMP(normalExitCtx.bb)) - - emitFinalizer(normalExitCtx) - } - } - } - - /** - * Represent a label in the current method code. In order - * to support forward jumps, labels can be created without - * having a designated target block. They can later be attached - * by calling `anchor`. - */ - class Label(val symbol: Symbol) { - var anchored = false - var block: BasicBlock = _ - var params: List[Symbol] = _ - - private var toPatch: List[Instruction] = Nil - - /** Fix this label to the given basic block. */ - def anchor(b: BasicBlock): Label = { - assert(!anchored, "Cannot anchor an already anchored label!") - anchored = true - this.block = b - this - } - - def setParams(p: List[Symbol]): Label = { - assert(params eq null, "Cannot set label parameters twice!") - params = p - this - } - - /** Add an instruction that refers to this label. */ - def addCallingInstruction(i: Instruction) = - toPatch = i :: toPatch - - /** - * Patch the code by replacing pseudo call instructions with - * jumps to the given basic block. - */ - def patch(code: Code) { - val map = mapFrom(toPatch)(patch) - code.blocks foreach (_ subst map) - } - - /** - * Return the patched instruction. If the given instruction - * jumps to this label, replace it with the basic block. Otherwise, - * return the same instruction. Conditional jumps have more than one - * label, so they are replaced only if all labels are anchored. - */ - def patch(instr: Instruction): Instruction = { - assert(anchored, "Cannot patch until this label is anchored: " + this) - - instr match { - case PJUMP(self) - if (self == this) => JUMP(block) - - case PCJUMP(self, failure, cond, kind) - if (self == this && failure.anchored) => - CJUMP(block, failure.block, cond, kind) - - case PCJUMP(success, self, cond, kind) - if (self == this && success.anchored) => - CJUMP(success.block, block, cond, kind) - - case PCZJUMP(self, failure, cond, kind) - if (self == this && failure.anchored) => - CZJUMP(block, failure.block, cond, kind) - - case PCZJUMP(success, self, cond, kind) - if (self == this && success.anchored) => - CZJUMP(success.block, block, cond, kind) - - case _ => instr - } - } - - override def toString() = symbol.toString() - } - - ///////////////// Fake instructions ////////////////////////// - - /** - * Pseudo jump: it takes a Label instead of a basic block. - * It is used temporarily during code generation. It is replaced - * by a real JUMP instruction when all labels are resolved. - */ - abstract class PseudoJUMP(label: Label) extends Instruction { - override def toString = s"PJUMP(${label.symbol})" - override def consumed = 0 - override def produced = 0 - - // register with the given label - if (!label.anchored) - label.addCallingInstruction(this) - } - - case class PJUMP(whereto: Label) extends PseudoJUMP(whereto) - - case class PCJUMP(success: Label, failure: Label, cond: TestOp, kind: TypeKind) - extends PseudoJUMP(success) { - override def toString(): String = - "PCJUMP (" + kind + ") " + success.symbol.simpleName + - " : " + failure.symbol.simpleName - - if (!failure.anchored) - failure.addCallingInstruction(this) - } - - case class PCZJUMP(success: Label, failure: Label, cond: TestOp, kind: TypeKind) - extends PseudoJUMP(success) { - override def toString(): String = - "PCZJUMP (" + kind + ") " + success.symbol.simpleName + - " : " + failure.symbol.simpleName - - if (!failure.anchored) - failure.addCallingInstruction(this) - } - - /** Local variable scopes. Keep track of line numbers for debugging info. */ - class Scope(val outer: Scope) { - val locals: ListBuffer[Local] = new ListBuffer - - def add(l: Local) = locals += l - - /** Return all locals that are in scope. */ - def varsInScope: Buffer[Local] = outer.varsInScope.clone() ++= locals - - override def toString() = locals.mkString(outer.toString + "[", ", ", "]") - } - - object EmptyScope extends Scope(null) { - override def toString() = "[]" - override def varsInScope: Buffer[Local] = new ListBuffer - } -} diff --git a/src/compiler/scala/tools/nsc/backend/icode/ICodeCheckers.scala b/src/compiler/scala/tools/nsc/backend/icode/ICodeCheckers.scala deleted file mode 100644 index 0f17b5d694..0000000000 --- a/src/compiler/scala/tools/nsc/backend/icode/ICodeCheckers.scala +++ /dev/null @@ -1,711 +0,0 @@ -/* NSC -- new Scala compiler - * Copyright 2005-2013 LAMP/EPFL - * @author Martin Odersky - */ - -package scala.tools.nsc -package backend -package icode - -import scala.collection.mutable -import scala.collection.mutable.ListBuffer - -abstract class ICodeCheckers { - val global: Global - import global._ - - /** <p> - * This class performs a set of checks similar to what the bytecode - * verifier does. For each basic block, it checks that: - * </p> - * <ul> - * <li> - * for primitive operations: the type and number of operands match - * the type of the operation - * </li> - * <li> - * for method calls: the method exists in the type of the receiver - * and the number and type of arguments match the declared type of - * the method. - * </li> - * <li> - * for object creation: the constructor can be called. - * </li> - * <li> - * for load/stores: the field/local/param exists and the type - * of the value matches that of the target. - * </li> - * </ul> - * <p> - * For a control flow graph it checks that type stacks at entry to - * each basic block 'agree': - * </p> - * <ul> - * <li>they have the same length</li> - * <li>there exists a lub for all types at the same position in stacks.</li> - * </ul> - * - * @author Iulian Dragos - * @version 1.0, 06/09/2005 - * - * @todo Better checks for `MONITOR_ENTER/EXIT` - * Better checks for local var initializations - * - * @todo Iulian says: I think there's some outdated logic in the checker. - * The issue with exception handlers being special for least upper - * bounds pointed out some refactoring in the lattice class. Maybe - * a worthwhile refactoring would be to make the checker use the - * DataFlowAnalysis class, and use the lattice trait. In the - * implementation of LUB, there's a flag telling if one of the - * successors is 'exceptional'. The inliner is using this mechanism. - */ - class ICodeChecker { - import icodes._ - import opcodes._ - - var clasz: IClass = _ - var method: IMethod = _ - var code: Code = _ - - val in: mutable.Map[BasicBlock, TypeStack] = perRunCaches.newMap() - val out: mutable.Map[BasicBlock, TypeStack] = perRunCaches.newMap() - val emptyStack = new TypeStack() { - override def toString = "<empty>" - } - - /** The presence of emptyStack means that path has not yet been checked - * (and may not be empty). - */ - def notChecked(ts: TypeStack) = ts eq emptyStack - def initMaps(bs: Seq[BasicBlock]): Unit = { - in.clear() - out.clear() - bs foreach { b => - in(b) = emptyStack - out(b) = emptyStack - } - } - - /** A wrapper to route log messages to debug output also. - */ - def logChecker(msg: String) = { - log(msg) - checkerDebug(msg) - } - - def checkICodes(): Unit = { - if (settings.verbose) - println("[[consistency check at the beginning of phase " + globalPhase.name + "]]") - classes.values foreach check - } - - private def posStr(p: Position) = - if (p.isDefined) p.line.toString else "<??>" - - private def indent(s: String, prefix: String): String = { - val lines = s split "\\n" - lines map (prefix + _) mkString "\n" - } - - /** Only called when m1 < m2, so already known that (m1 ne m2). - */ - private def isConflict(m1: IMember, m2: IMember, canOverload: Boolean) = ( - (m1.symbol.name == m2.symbol.name) && - (!canOverload || (m1.symbol.tpe =:= m2.symbol.tpe)) - ) - - def check(cls: IClass) { - logChecker("\n<<-- Checking class " + cls + " -->>") - clasz = cls - - for (f1 <- cls.fields ; f2 <- cls.fields ; if f1 < f2) - if (isConflict(f1, f2, canOverload = false)) - icodeError("Repetitive field name: " + f1.symbol.fullName) - - for (m1 <- cls.methods ; m2 <- cls.methods ; if m1 < m2) - if (isConflict(m1, m2, canOverload = true)) - icodeError("Repetitive method: " + m1.symbol.fullName) - - clasz.methods foreach check - } - - def check(m: IMethod) { - logChecker("\n<< Checking method " + m.symbol.name + " >>") - method = m - if (!m.isAbstractMethod) - check(m.code) - } - - def check(c: Code) { - val worklist = new ListBuffer[BasicBlock] - def append(elems: List[BasicBlock]) = - worklist ++= (elems filterNot (worklist contains _)) - - code = c - worklist += c.startBlock - initMaps(c.blocks) - - while (worklist.nonEmpty) { - val block = worklist remove 0 - val output = check(block, in(block)) - if (output != out(block) || notChecked(out(block))) { - if (block.successors.nonEmpty) - logChecker("** Output change for %s: %s -> %s".format(block, out(block), output)) - - out(block) = output - append(block.successors) - block.successors foreach meet - } - } - } - - /** - * Apply the meet operator of the stack lattice on bl's predecessors. - * :-). Compute the input to bl by checking that all stacks have the - * same length, and taking the lub of types at the same positions. - */ - def meet(bl: BasicBlock) { - val preds = bl.predecessors - - def hasNothingType(s: TypeStack) = s.nonEmpty && (s.head == NothingReference) - - /* XXX workaround #1: one stack empty, the other has BoxedUnit. - * One example where this arises is: - * - * def f(b: Boolean): Unit = synchronized { if (b) () } - */ - def allUnits(s: TypeStack) = s.types forall (_ == BoxedUnitReference) - - def ifAthenB[T](f: T => Boolean): PartialFunction[(T, T), T] = { - case (x1, x2) if f(x1) => x2 - case (x1, x2) if f(x2) => x1 - } - - /* XXX workaround #2: different stacks heading into an exception - * handler which will clear them anyway. Examples where it arises: - * - * var bippy: Int = synchronized { if (b) 5 else 10 } - */ - def isHandlerBlock() = bl.exceptionHandlerStart - - def meet2(s1: TypeStack, s2: TypeStack): TypeStack = { - def workaround(msg: String) = { - checkerDebug(msg + ": " + method + " at block " + bl) - checkerDebug(" s1: " + s1) - checkerDebug(" s2: " + s2) - new TypeStack() - } - def incompatibleString = ( - "Incompatible stacks: " + s1 + " and " + s2 + " in " + method + " at entry to block " + bl.label + ":\n" + - indent(bl.predContents, "// ") + - indent(bl.succContents, "// ") + - indent(bl.blockContents, "// ") - ) - - val f: ((TypeStack, TypeStack)) => TypeStack = { - ifAthenB(notChecked) orElse ifAthenB(hasNothingType) orElse { - case (s1: TypeStack, s2: TypeStack) => - if (s1.length != s2.length) { - if (allUnits(s1) && allUnits(s2)) - workaround("Ignoring mismatched boxed units") - else if (isHandlerBlock()) - workaround("Ignoring mismatched stacks entering exception handler") - else - throw new CheckerException(incompatibleString) - } - else { - val newStack: TypeStack = try { - new TypeStack((s1.types, s2.types).zipped map lub) - } catch { - case t: Exception => - checkerDebug(t.toString + ": " + s1.types.toString + " vs " + s2.types.toString) - new TypeStack(s1.types) - } - if (newStack.isEmpty || s1.types == s2.types) () // not interesting to report - else checkerDebug("Checker created new stack:\n (%s, %s) => %s".format(s1, s2, newStack)) - - newStack - } - } - } - - f((s1, s2)) - } - - if (preds.nonEmpty) { - in(bl) = (preds map out.apply) reduceLeft meet2 - log("Input changed for block: " + bl +" to: " + in(bl)) - } - } - - private var instruction: Instruction = null - private var basicBlock: BasicBlock = null - private var stringConcatDepth = 0 - private def stringConcatIndent() = " " * stringConcatDepth - private def currentInstrString: String = { - val (indent, str) = this.instruction match { - case CALL_PRIMITIVE(StartConcat) => - val x = stringConcatIndent() - stringConcatDepth += 1 - (x, "concat(") - case CALL_PRIMITIVE(EndConcat) => - if (stringConcatDepth > 0) { - stringConcatDepth -= 1 - (stringConcatIndent(), ") // end concat") - } - else ("", "") - case _ => - (stringConcatIndent(), this.instruction match { - case CALL_PRIMITIVE(StringConcat(el)) => "..." - case null => "null" - case cm @ CALL_METHOD(_, _) => if (clasz.symbol == cm.hostClass) cm.toShortString else cm.toString - case x => x.toString - }) - } - indent + str - } - /** A couple closure creators to reduce noise in the output: when multiple - * items are pushed or popped, this lets us print something short and sensible - * for those beyond the first. - */ - def mkInstrPrinter(f: Int => String): () => String = { - var counter = -1 - val indent = stringConcatIndent() - () => { - counter += 1 - if (counter == 0) currentInstrString - else indent + f(counter) - } - } - def defaultInstrPrinter: () => String = mkInstrPrinter(_ => "\"\"\"") - - /** - * Check the basic block to be type correct and return the - * produced type stack. - */ - def check(b: BasicBlock, initial: TypeStack): TypeStack = { - this.basicBlock = b - - logChecker({ - val prefix = "** Checking " + b.fullString - - if (initial.isEmpty) prefix - else prefix + " with initial stack " + initial.types.mkString("[", ", ", "]") - }) - - val stack = new TypeStack(initial) - def checkStack(len: Int) { - if (stack.length < len) - ICodeChecker.this.icodeError("Expected at least " + len + " elements on the stack", stack) - } - - def sizeString(push: Boolean) = { - val arrow = if (push) "-> " else "<- " - val sp = " " * stack.length - - sp + stack.length + arrow - } - def printStackString(isPush: Boolean, value: TypeKind, instrString: String) = { - val pushString = if (isPush) "+" else "-" - val posString = posStr(this.instruction.pos) - - checkerDebug("%-70s %-4s %s %s".format(sizeString(isPush) + value, posString, pushString, instrString)) - } - def _popStack: TypeKind = { - if (stack.isEmpty) { - icodeError("Popped empty stack in " + b.fullString + ", throwing a Unit") - return UNIT - } - stack.pop - } - def popStackN(num: Int, instrFn: () => String = defaultInstrPrinter) = { - List.range(0, num) map { _ => - val res = _popStack - printStackString(isPush = false, res, instrFn()) - res - } - } - def pushStackN(xs: Seq[TypeKind], instrFn: () => String) = { - xs foreach { x => - stack push x - printStackString(isPush = true, x, instrFn()) - } - } - - def popStack = { checkStack(1) ; (popStackN(1): @unchecked) match { case List(x) => x } } - def popStack2 = { checkStack(2) ; (popStackN(2): @unchecked) match { case List(x, y) => (x, y) } } - def popStack3 = { checkStack(3) ; (popStackN(3): @unchecked) match { case List(x, y, z) => (x, y, z) } } - - /* Called by faux instruction LOAD_EXCEPTION to wipe out the stack. */ - def clearStack() = { - if (stack.nonEmpty) - logChecker("Wiping out the " + stack.length + " element stack for exception handler: " + stack) - - 1 to stack.length foreach (_ => popStack) - } - - def pushStack(xs: TypeKind*): Unit = { - pushStackN(xs filterNot (_ == UNIT), defaultInstrPrinter) - } - - def typeError(k1: TypeKind, k2: TypeKind) { - icodeError("\n expected: " + k1 + "\n found: " + k2) - } - def isSubtype(k1: TypeKind, k2: TypeKind) = (k1 isAssignabledTo k2) || { - import platform.isMaybeBoxed - - (k1, k2) match { - case (REFERENCE(_), REFERENCE(_)) if k1.isInterfaceType || k2.isInterfaceType => - logChecker("Considering %s <:< %s because at least one is an interface".format(k1, k2)) - true - case (REFERENCE(cls1), REFERENCE(cls2)) if isMaybeBoxed(cls1) || isMaybeBoxed(cls2) => - logChecker("Considering %s <:< %s because at least one might be a boxed primitive".format(cls1, cls2)) - true - case _ => - false - } - } - - def subtypeTest(k1: TypeKind, k2: TypeKind): Unit = - if (isSubtype(k1, k2)) () - else typeError(k2, k1) - - for (instr <- b) { - this.instruction = instr - - def checkLocal(local: Local) { - if ((method lookupLocal local.sym.name).isEmpty) - icodeError(s" $local is not defined in method $method") - } - def checkField(obj: TypeKind, field: Symbol): Unit = obj match { - case REFERENCE(sym) => - if (sym.info.member(field.name) == NoSymbol) - icodeError(" " + field + " is not defined in class " + clasz) - case _ => - icodeError(" expected reference type, but " + obj + " found") - } - - /* Checks that tpe is a subtype of one of the allowed types */ - def checkType(tpe: TypeKind, allowed: TypeKind*) = ( - if (allowed exists (k => isSubtype(tpe, k))) () - else icodeError(tpe + " is not one of: " + allowed.mkString("{ ", ", ", " }")) - ) - def checkNumeric(tpe: TypeKind) = - checkType(tpe, BYTE, CHAR, SHORT, INT, LONG, FLOAT, DOUBLE) - - /* Checks that the 2 topmost elements on stack are of the kind TypeKind. */ - def checkBinop(kind: TypeKind) { - val (a, b) = popStack2 - checkType(a, kind) - checkType(b, kind) - } - - /* Check that arguments on the stack match method params. */ - def checkMethodArgs(method: Symbol) { - val params = method.info.paramTypes - checkStack(params.length) - ( - popStackN(params.length, mkInstrPrinter(num => "<arg" + num + ">")), - params.reverse map toTypeKind).zipped foreach ((x, y) => checkType(x, y) - ) - } - - /* Checks that the object passed as receiver has a method - * `method` and that it is callable from the current method. - */ - def checkMethod(receiver: TypeKind, method: Symbol) = - receiver match { - case REFERENCE(sym) => - checkBool(sym.info.member(method.name) != NoSymbol, - "Method " + method + " does not exist in " + sym.fullName) - if (method.isPrivate) - checkBool(method.owner == clasz.symbol, - "Cannot call private method of " + method.owner.fullName - + " from " + clasz.symbol.fullName) - else if (method.isProtected) { - val isProtectedOK = ( - (clasz.symbol isSubClass method.owner) || - (clasz.symbol.typeOfThis.typeSymbol isSubClass method.owner) // see pos/bug780.scala - ) - - checkBool(isProtectedOK, - "Cannot call protected method of " + method.owner.fullName - + " from " + clasz.symbol.fullName) - } - - case ARRAY(_) => - checkBool(receiver.toType.member(method.name) != NoSymbol, - "Method " + method + " does not exist in " + receiver) - - case t => - icodeError("Not a reference type: " + t) - } - - def checkBool(cond: Boolean, msg: String) = - if (!cond) icodeError(msg) - - if (settings.debug) { - log("PC: " + instr) - log("stack: " + stack) - log("================") - } - instr match { - case THIS(clasz) => - pushStack(toTypeKind(clasz.tpe)) - - case CONSTANT(const) => - pushStack(toTypeKind(const.tpe)) - - case LOAD_ARRAY_ITEM(kind) => - popStack2 match { - case (INT, ARRAY(elem)) => - subtypeTest(elem, kind) - pushStack(elem) - case (a, b) => - icodeError(" expected an INT and an array reference, but " + - a + ", " + b + " found") - } - - case LOAD_LOCAL(local) => - checkLocal(local) - pushStack(local.kind) - - case LOAD_FIELD(field, isStatic) => - // the symbol's owner should contain its field, but - // this is already checked by the type checker, no need - // to redo that here - if (isStatic) () - else checkField(popStack, field) - - pushStack(toTypeKind(field.tpe)) - - case LOAD_MODULE(module) => - checkBool((module.isModule || module.isModuleClass), - "Expected module: " + module + " flags: " + module.flagString) - pushStack(toTypeKind(module.tpe)) - - case STORE_THIS(kind) => - val actualType = popStack - if (actualType.isReferenceType) subtypeTest(actualType, kind) - else icodeError("Expected this reference but found: " + actualType) - - case STORE_ARRAY_ITEM(kind) => - popStack3 match { - case (k, INT, ARRAY(elem)) => - subtypeTest(k, kind) - subtypeTest(k, elem) - case (a, b, c) => - icodeError(" expected and array reference, and int and " + kind + - " but " + a + ", " + b + ", " + c + " found") - } - - case STORE_LOCAL(local) => - checkLocal(local) - val actualType = popStack - if (local.kind != NullReference) - subtypeTest(actualType, local.kind) - - case STORE_FIELD(field, true) => // static - val fieldType = toTypeKind(field.tpe) - val actualType = popStack - subtypeTest(actualType, fieldType) - - case STORE_FIELD(field, false) => // not static - val (value, obj) = popStack2 - checkField(obj, field) - val fieldType = toTypeKind(field.tpe) - if (fieldType == NullReference) () - else subtypeTest(value, fieldType) - - case CALL_PRIMITIVE(primitive) => - checkStack(instr.consumed) - primitive match { - case Negation(kind) => - checkType(kind, BOOL, BYTE, CHAR, SHORT, INT, LONG, FLOAT, DOUBLE) - checkType(popStack, kind) - pushStack(kind) - - case Test(op, kind, zero) => - if (zero) checkType(popStack, kind) - else checkBinop(kind) - - pushStack(BOOL) - - case Comparison(op, kind) => - checkNumeric(kind) - checkBinop(kind) - pushStack(INT) - - case Arithmetic(op, kind) => - checkNumeric(kind) - if (op == NOT) - checkType(popStack, kind) - else - checkBinop(kind) - pushStack(kind) - - case Logical(op, kind) => - checkType(kind, BOOL, BYTE, CHAR, SHORT, INT, LONG) - checkBinop(kind) - pushStack(kind) - - case Shift(op, kind) => - checkType(kind, BYTE, CHAR, SHORT, INT, LONG) - val (a, b) = popStack2 - checkType(a, INT) - checkType(b, kind) - pushStack(kind) - - case Conversion(src, dst) => - checkNumeric(src) - checkNumeric(dst) - checkType(popStack, src) - pushStack(dst) - - case ArrayLength(kind) => - popStack match { - case ARRAY(elem) => checkType(elem, kind) - case arr => icodeError(" array reference expected, but " + arr + " found") - } - pushStack(INT) - - case StartConcat => - pushStack(ConcatClass) - - case EndConcat => - checkType(popStack, ConcatClass) - pushStack(StringReference) - - case StringConcat(el) => - checkType(popStack, el) - checkType(popStack, ConcatClass) - pushStack(ConcatClass) - } - - case CALL_METHOD(method, style) => - // PP to ID: I moved the if (!method.isConstructor) check to cover all - // the styles to address checker failure. Can you confirm if the change - // was correct? If I remember right it's a matter of whether some brand - // of supercall should leave a value on the stack, and I know there is some - // trickery performed elsewhere regarding this. - val paramCount = method.info.paramTypes.length match { - case x if style.hasInstance => x + 1 - case x => x - } - if (style == Static(onInstance = true)) - checkBool(method.isPrivate || method.isConstructor, "Static call to non-private method.") - - checkStack(paramCount) - checkMethodArgs(method) - if (style.hasInstance) - checkMethod(popStack, method) - if (!method.isConstructor) - pushStack(toTypeKind(method.info.resultType)) - - case NEW(kind) => - pushStack(kind) - - case CREATE_ARRAY(elem, dims) => - checkStack(dims) - stack.pop(dims) foreach (checkType(_, INT)) - pushStack(ARRAY(elem)) - - case IS_INSTANCE(tpe) => - val ref = popStack - checkBool(!ref.isValueType, "IS_INSTANCE on primitive type: " + ref) - checkBool(!tpe.isValueType, "IS_INSTANCE on primitive type: " + tpe) - pushStack(BOOL) - - case CHECK_CAST(tpe) => - val ref = popStack - checkBool(!ref.isValueType, "CHECK_CAST to primitive type: " + ref) - checkBool(!tpe.isValueType, "CHECK_CAST to primitive type: " + tpe) - pushStack(tpe) - - case SWITCH(tags, labels) => - checkType(popStack, INT) - checkBool(tags.length == labels.length - 1, - "The number of tags and labels does not coincide.") - checkBool(labels forall (b => code.blocks contains b), - "Switch target cannot be found in code.") - - case JUMP(whereto) => - checkBool(code.blocks contains whereto, - "Jump to non-existant block " + whereto) - - case CJUMP(success, failure, cond, kind) => - checkBool(code.blocks contains success, - "Jump to non-existant block " + success) - checkBool(code.blocks contains failure, - "Jump to non-existant block " + failure) - checkBinop(kind) - - case CZJUMP(success, failure, cond, kind) => - checkBool(code.blocks contains success, - "Jump to non-existant block " + success) - checkBool(code.blocks contains failure, - "Jump to non-existant block " + failure) - checkType(popStack, kind) - - case RETURN(UNIT) => () - case RETURN(kind) => - val top = popStack - if (kind.isValueType) checkType(top, kind) - else checkBool(!top.isValueType, "" + kind + " is a reference type, but " + top + " is not") - - case THROW(clasz) => - checkType(popStack, toTypeKind(clasz.tpe)) - pushStack(NothingReference) - - case DROP(kind) => - checkType(popStack, kind) - - case DUP(kind) => - val top = popStack - checkType(top, kind) - pushStack(top) - pushStack(top) - - case MONITOR_ENTER() => - checkBool(popStack.isReferenceType, "MONITOR_ENTER on non-reference type") - - case MONITOR_EXIT() => - checkBool(popStack.isReferenceType, "MONITOR_EXIT on non-reference type") - - case BOX(kind) => - checkType(popStack, kind) - pushStack(REFERENCE(definitions.boxedClass(kind.toType.typeSymbol))) - - case UNBOX(kind) => - popStack - pushStack(kind) - - case LOAD_EXCEPTION(clasz) => - clearStack() - pushStack(REFERENCE(clasz)) - - case SCOPE_ENTER(_) | SCOPE_EXIT(_) => - () - - case _ => - abort("Unknown instruction: " + instr) - } - } - stack - } - - //////////////// Error reporting ///////////////////////// - - def icodeError(msg: String) { - ICodeCheckers.this.global.warning( - "!! ICode checker fatality in " + method + - "\n at: " + basicBlock.fullString + - "\n error message: " + msg - ) - } - - def icodeError(msg: String, stack: TypeStack) { - icodeError(msg + "\n type stack: " + stack) - } - } -} diff --git a/src/compiler/scala/tools/nsc/backend/icode/ICodes.scala b/src/compiler/scala/tools/nsc/backend/icode/ICodes.scala deleted file mode 100644 index 10f0c6ee00..0000000000 --- a/src/compiler/scala/tools/nsc/backend/icode/ICodes.scala +++ /dev/null @@ -1,129 +0,0 @@ -/* NSC -- new scala compiler - * Copyright 2005-2013 LAMP/EPFL - * @author Martin Odersky - */ - -package scala.tools.nsc -package backend -package icode - -import java.io.PrintWriter -import analysis.{ Liveness, ReachingDefinitions } -import scala.tools.nsc.symtab.classfile.ICodeReader -import scala.reflect.io.AbstractFile - -/** Glue together ICode parts. - * - * @author Iulian Dragos - */ -abstract class ICodes extends AnyRef - with Members - with BasicBlocks - with Opcodes - with TypeStacks - with TypeKinds - with ExceptionHandlers - with Primitives - with Linearizers - with Printers - with Repository -{ - val global: Global - import global.{ log, definitions, settings, perRunCaches, devWarning } - - /** The ICode representation of classes */ - val classes = perRunCaches.newMap[global.Symbol, IClass]() - - /** Debugging flag */ - def shouldCheckIcode = settings.check contains global.genicode.phaseName - def checkerDebug(msg: String) = if (shouldCheckIcode && global.settings.debug) println(msg) - - /** The ICode linearizer. */ - val linearizer: Linearizer = settings.Xlinearizer.value match { - case "rpo" => new ReversePostOrderLinearizer() - case "dfs" => new DepthFirstLinerizer() - case "normal" => new NormalLinearizer() - case "dump" => new DumpLinearizer() - case x => global.abort("Unknown linearizer: " + x) - } - - def newTextPrinter() = - new TextPrinter(new PrintWriter(Console.out, true), new DumpLinearizer) - - /** Have to be careful because dump calls around, possibly - * re-entering methods which initiated the dump (like foreach - * in BasicBlocks) which leads to the icode output olympics. - */ - private var alreadyDumping = false - - /** Print all classes and basic blocks. Used for debugging. */ - - def dumpClassesAndAbort(msg: String): Nothing = { - if (alreadyDumping) global.abort(msg) - else alreadyDumping = true - - Console.println(msg) - val printer = newTextPrinter() - classes.values foreach printer.printClass - global.abort(msg) - } - - def dumpMethodAndAbort(m: IMethod, msg: String): Nothing = { - Console.println("Fatal bug in inlinerwhile traversing " + m + ": " + msg) - m.dump() - global.abort("" + m) - } - def dumpMethodAndAbort(m: IMethod, b: BasicBlock): Nothing = - dumpMethodAndAbort(m, "found open block " + b + " " + b.flagsString) - - def checkValid(m: IMethod) { - // always slightly dicey to iterate over mutable structures - m foreachBlock { b => - if (!b.closed) { - // Something is leaving open/empty blocks around (see SI-4840) so - // let's not kill the deal unless it's nonempty. - if (b.isEmpty) { - devWarning(s"Found open but empty block while inlining $m: removing from block list.") - m.code removeBlock b - } - else dumpMethodAndAbort(m, b) - } - } - } - - object liveness extends Liveness { - val global: ICodes.this.global.type = ICodes.this.global - } - - object reachingDefinitions extends ReachingDefinitions { - val global: ICodes.this.global.type = ICodes.this.global - } - - lazy val AnyRefReference: TypeKind = REFERENCE(definitions.AnyRefClass) - lazy val BoxedUnitReference: TypeKind = REFERENCE(definitions.BoxedUnitClass) - lazy val NothingReference: TypeKind = REFERENCE(definitions.NothingClass) - lazy val NullReference: TypeKind = REFERENCE(definitions.NullClass) - lazy val ObjectReference: TypeKind = REFERENCE(definitions.ObjectClass) - lazy val StringReference: TypeKind = REFERENCE(definitions.StringClass) - - object icodeReader extends ICodeReader { - lazy val global: ICodes.this.global.type = ICodes.this.global - import global._ - def lookupMemberAtTyperPhaseIfPossible(sym: Symbol, name: Name): Symbol = - global.loaders.lookupMemberAtTyperPhaseIfPossible(sym, name) - lazy val symbolTable: global.type = global - lazy val loaders: global.loaders.type = global.loaders - - def classFileLookup: util.ClassFileLookup[AbstractFile] = global.classPath - } - - /** A phase which works on icode. */ - abstract class ICodePhase(prev: Phase) extends global.GlobalPhase(prev) { - override def erasedTypes = true - override def apply(unit: global.CompilationUnit): Unit = - unit.icode foreach apply - - def apply(cls: global.icodes.IClass): Unit - } -} - diff --git a/src/compiler/scala/tools/nsc/backend/icode/Linearizers.scala b/src/compiler/scala/tools/nsc/backend/icode/Linearizers.scala deleted file mode 100644 index 54be9d18f1..0000000000 --- a/src/compiler/scala/tools/nsc/backend/icode/Linearizers.scala +++ /dev/null @@ -1,201 +0,0 @@ -/* NSC -- new scala compiler - * Copyright 2005-2013 LAMP/EPFL - * @author Martin Odersky - */ - - -package scala -package tools.nsc -package backend -package icode - -import scala.collection.{ mutable, immutable } -import mutable.ListBuffer - -trait Linearizers { - self: ICodes => - - import global.debuglog - import opcodes._ - - abstract class Linearizer { - def linearize(c: IMethod): List[BasicBlock] - def linearizeAt(c: IMethod, start: BasicBlock): List[BasicBlock] - } - - /** - * A simple linearizer which predicts all branches to - * take the 'success' branch and tries to schedule those - * blocks immediately after the test. This is in sync with - * how 'while' statements are translated (if the test is - * 'true', the loop continues). - */ - class NormalLinearizer extends Linearizer with WorklistAlgorithm { - type Elem = BasicBlock - val worklist: WList = new mutable.Stack() - var blocks: List[BasicBlock] = Nil - - def linearize(m: IMethod): List[BasicBlock] = { - val b = m.startBlock - blocks = Nil - - run { - worklist pushAll (m.exh map (_.startBlock)) - worklist.push(b) - } - - blocks.reverse - } - - def linearizeAt(m: IMethod, start: BasicBlock): List[BasicBlock] = { - blocks = Nil - worklist.clear() - linearize(start) - } - - /** Linearize another subtree and append it to the existing blocks. */ - def linearize(startBlock: BasicBlock): List[BasicBlock] = { - //blocks = startBlock :: Nil; - run( { worklist.push(startBlock); } ) - blocks.reverse - } - - def processElement(b: BasicBlock) = - if (b.nonEmpty) { - add(b) - b.lastInstruction match { - case JUMP(whereto) => - add(whereto) - case CJUMP(success, failure, _, _) => - add(success) - add(failure) - case CZJUMP(success, failure, _, _) => - add(success) - add(failure) - case SWITCH(_, labels) => - add(labels) - case RETURN(_) => () - case THROW(clasz) => () - } - } - - def dequeue: Elem = worklist.pop() - - /** - * Prepend b to the list, if not already scheduled. - * TODO: use better test than linear search - */ - def add(b: BasicBlock) { - if (blocks.contains(b)) - () - else { - blocks = b :: blocks - worklist push b - } - } - - def add(bs: List[BasicBlock]): Unit = bs foreach add - } - - /** - * Linearize code using a depth first traversal. - */ - class DepthFirstLinerizer extends Linearizer { - var blocks: List[BasicBlock] = Nil - - def linearize(m: IMethod): List[BasicBlock] = { - blocks = Nil - - dfs(m.startBlock) - m.exh foreach (b => dfs(b.startBlock)) - - blocks.reverse - } - - def linearizeAt(m: IMethod, start: BasicBlock): List[BasicBlock] = { - blocks = Nil - dfs(start) - blocks.reverse - } - - def dfs(b: BasicBlock): Unit = - if (b.nonEmpty && add(b)) - b.successors foreach dfs - - /** - * Prepend b to the list, if not already scheduled. - * TODO: use better test than linear search - * @return Returns true if the block was added. - */ - def add(b: BasicBlock): Boolean = - !(blocks contains b) && { - blocks = b :: blocks - true - } - } - - /** - * Linearize code in reverse post order. In fact, it does - * a post order traversal, prepending visited nodes to the list. - * This way, it is constructed already in reverse post order. - */ - class ReversePostOrderLinearizer extends Linearizer { - var blocks: List[BasicBlock] = Nil - val visited = new mutable.HashSet[BasicBlock] - val added = new mutable.BitSet - - def linearize(m: IMethod): List[BasicBlock] = { - blocks = Nil - visited.clear() - added.clear() - - m.exh foreach (b => rpo(b.startBlock)) - rpo(m.startBlock) - - // if the start block has predecessors, it won't be the first one - // in the linearization, so we need to enforce it here - if (m.startBlock.predecessors eq Nil) - blocks - else - m.startBlock :: (blocks.filterNot(_ == m.startBlock)) - } - - def linearizeAt(m: IMethod, start: BasicBlock): List[BasicBlock] = { - blocks = Nil - visited.clear() - added.clear() - - rpo(start) - blocks - } - - def rpo(b: BasicBlock): Unit = - if (b.nonEmpty && !visited(b)) { - visited += b - b.successors foreach rpo - add(b) - } - - /** - * Prepend b to the list, if not already scheduled. - * @return Returns true if the block was added. - */ - def add(b: BasicBlock) = { - debuglog("Linearizer adding block " + b.label) - - if (!added(b.label)) { - added += b.label - blocks = b :: blocks - } - } - } - - /** A 'dump' of the blocks in this method, which does not - * require any well-formedness of the basic blocks (like - * the last instruction being a jump). - */ - class DumpLinearizer extends Linearizer { - def linearize(m: IMethod): List[BasicBlock] = m.blocks - def linearizeAt(m: IMethod, start: BasicBlock): List[BasicBlock] = sys.error("not implemented") - } -} diff --git a/src/compiler/scala/tools/nsc/backend/icode/Members.scala b/src/compiler/scala/tools/nsc/backend/icode/Members.scala deleted file mode 100644 index 64146585e5..0000000000 --- a/src/compiler/scala/tools/nsc/backend/icode/Members.scala +++ /dev/null @@ -1,296 +0,0 @@ -/* NSC -- new scala compiler - * Copyright 2005-2013 LAMP/EPFL - * @author Martin Odersky - */ - -package scala -package tools.nsc -package backend -package icode - -import scala.collection.{ mutable, immutable } -import scala.reflect.internal.util.{ SourceFile, NoSourceFile } - -trait ReferenceEquality { - override def hashCode = System.identityHashCode(this) - override def equals(that: Any) = this eq that.asInstanceOf[AnyRef] -} - -trait Members { - self: ICodes => - - import global._ - - object NoCode extends Code(null, TermName("NoCode")) { - override def blocksList: List[BasicBlock] = Nil - } - - /** - * This class represents the intermediate code of a method or - * other multi-block piece of code, like exception handlers. - */ - class Code(method: IMethod, name: Name) { - def this(method: IMethod) = this(method, method.symbol.name) - /** The set of all blocks */ - val blocks = mutable.ListBuffer[BasicBlock]() - - /** The start block of the method */ - var startBlock: BasicBlock = NoBasicBlock - - private var currentLabel: Int = 0 - private var _touched = false - - def blocksList: List[BasicBlock] = blocks.toList - def instructions = blocksList flatMap (_.iterator) - def blockCount = blocks.size - def instructionCount = (blocks map (_.length)).sum - - def touched = _touched - def touched_=(b: Boolean): Unit = { - @annotation.tailrec def loop(xs: List[BasicBlock]) { - xs match { - case Nil => - case x :: xs => x.touched = true ; loop(xs) - } - } - if (b) loop(blocks.toList) - - _touched = b - } - - // Constructor code - startBlock = newBlock() - - def removeBlock(b: BasicBlock) { - if (settings.debug) { - // only do this sanity check when debug is turned on because it's moderately expensive - val referers = blocks filter (_.successors contains b) - assert(referers.isEmpty, s"Trying to removing block $b (with preds ${b.predecessors.mkString}) but it is still refered to from block(s) ${referers.mkString}") - } - - if (b == startBlock) { - assert(b.successors.length == 1, - s"Removing start block ${b} with ${b.successors.length} successors (${b.successors.mkString})." - ) - startBlock = b.successors.head - } - - blocks -= b - assert(!blocks.contains(b)) - method.exh filter (_ covers b) foreach (_.covered -= b) - touched = true - } - - /** This methods returns a string representation of the ICode */ - override def toString = "ICode '" + name.decoded + "'" - - /* Compute a unique new label */ - def nextLabel: Int = { - currentLabel += 1 - currentLabel - } - - /* Create a new block and append it to the list - */ - def newBlock(): BasicBlock = { - touched = true - val block = new BasicBlock(nextLabel, method) - blocks += block - block - } - } - - /** Common interface for IClass/IField/IMethod. */ - trait IMember extends Ordered[IMember] { - def symbol: Symbol - - def compare(other: IMember) = - if (symbol eq other.symbol) 0 - else if (symbol isLess other.symbol) -1 - else 1 - - override def equals(other: Any): Boolean = - other match { - case other: IMember => (this compare other) == 0 - case _ => false - } - - override def hashCode = symbol.## - } - - /** Represent a class in ICode */ - class IClass(val symbol: Symbol) extends IMember { - var fields: List[IField] = Nil - var methods: List[IMethod] = Nil - var cunit: CompilationUnit = _ - - def addField(f: IField): this.type = { - fields = f :: fields - this - } - - def addMethod(m: IMethod): this.type = { - methods = m :: methods - this - } - - def setCompilationUnit(unit: CompilationUnit): this.type = { - this.cunit = unit - this - } - - override def toString() = symbol.fullName - - def lookupMethod(s: Symbol) = methods find (_.symbol == s) - - /* returns this methods static ctor if it has one. */ - def lookupStaticCtor: Option[IMethod] = methods find (_.symbol.isStaticConstructor) - } - - /** Represent a field in ICode */ - class IField(val symbol: Symbol) extends IMember { } - - object NoIMethod extends IMethod(NoSymbol) { } - - /** - * Represents a method in ICode. Local variables contain - * both locals and parameters, similar to the way the JVM - * 'sees' them. - * - * Locals and parameters are added in reverse order, as they - * are kept in cons-lists. The 'builder' is responsible for - * reversing them and putting them back, when the generation is - * finished (GenICode does that). - */ - class IMethod(val symbol: Symbol) extends IMember { - var code: Code = NoCode - - def newBlock() = code.newBlock() - def startBlock = code.startBlock - def lastBlock = { assert(blocks.nonEmpty, symbol); blocks.last } - def blocks = code.blocksList - def linearizedBlocks(lin: Linearizer = self.linearizer): List[BasicBlock] = lin linearize this - - def foreachBlock[U](f: BasicBlock => U): Unit = blocks foreach f - - var native = false - - /** The list of exception handlers, ordered from innermost to outermost. */ - var exh: List[ExceptionHandler] = Nil - var sourceFile: SourceFile = NoSourceFile - var returnType: TypeKind = _ - var recursive: Boolean = false - var bytecodeHasEHs = false // set by ICodeReader only, used by Inliner to prevent inlining (SI-6188) - var bytecodeHasInvokeDynamic = false // set by ICodeReader only, used by Inliner to prevent inlining until we have proper invoke dynamic support - - /** local variables and method parameters */ - var locals: List[Local] = Nil - - /** method parameters */ - var params: List[Local] = Nil - - def hasCode = code ne NoCode - def setCode(code: Code): IMethod = { - this.code = code - this - } - - final def updateRecursive(called: Symbol): Unit = { - recursive ||= (called == symbol) - } - - def addLocal(l: Local): Local = findOrElse(locals)(_ == l) { locals ::= l ; l } - - def addParam(p: Local): Unit = - if (params contains p) () - else { - params ::= p - locals ::= p - } - - def addLocals(ls: List[Local]) = ls foreach addLocal - - def lookupLocal(n: Name): Option[Local] = locals find (_.sym.name == n) - def lookupLocal(sym: Symbol): Option[Local] = locals find (_.sym == sym) - - def addHandler(e: ExceptionHandler) = exh ::= e - - /** Is this method deferred ('abstract' in Java sense)? - */ - def isAbstractMethod = symbol.isDeferred || symbol.owner.isInterface || native - - def isStatic: Boolean = symbol.isStaticMember - - override def toString() = symbol.fullName - - import opcodes._ - - /** Merge together blocks that have a single successor which has a - * single predecessor. Exception handlers are taken into account (they - * might force to break a block of straight line code like that). - * - * This method should be most effective after heavy inlining. - */ - def normalize(): Unit = if (this.hasCode) { - val nextBlock: mutable.Map[BasicBlock, BasicBlock] = mutable.HashMap.empty - for (b <- code.blocks.toList - if b.successors.length == 1; - succ = b.successors.head - if succ ne b - if succ.predecessors.length == 1 - if succ.predecessors.head eq b - if !(exh.exists { (e: ExceptionHandler) => - (e.covers(succ) && !e.covers(b)) || (e.covers(b) && !e.covers(succ)) })) { - nextBlock(b) = succ - } - - var bb = code.startBlock - while (!nextBlock.isEmpty) { - if (nextBlock.isDefinedAt(bb)) { - bb.open() - var succ = bb - do { - succ = nextBlock(succ) - val lastInstr = bb.lastInstruction - /* Ticket SI-5672 - * Besides removing the control-flow instruction at the end of `bb` (usually a JUMP), we have to pop any values it pushes. - * Examples: - * `SWITCH` consisting of just the default case, or - * `CJUMP(targetBlock, targetBlock, _, _)` ie where success and failure targets coincide (this one consumes two stack values). - */ - val oldTKs = lastInstr.consumedTypes - assert(lastInstr.consumed == oldTKs.size, "Someone forgot to override consumedTypes() in " + lastInstr) - - bb.removeLastInstruction() - for(tk <- oldTKs.reverse) { bb.emit(DROP(tk), lastInstr.pos) } - succ.toList foreach { i => bb.emit(i, i.pos) } - code.removeBlock(succ) - exh foreach { e => e.covered = e.covered - succ } - - nextBlock -= bb - } while (nextBlock.isDefinedAt(succ)) - bb.close() - } else - bb = nextBlock.keysIterator.next() - } - checkValid(this) - } - - def dump() { - Console.println("dumping IMethod(" + symbol + ")") - newTextPrinter() printMethod this - } - } - - /** Represent local variables and parameters */ - class Local(val sym: Symbol, val kind: TypeKind, val arg: Boolean) { - var index: Int = -1 - - override def equals(other: Any): Boolean = other match { - case x: Local => sym == x.sym - case _ => false - } - override def hashCode = sym.hashCode - override def toString(): String = sym.toString - } -} diff --git a/src/compiler/scala/tools/nsc/backend/icode/Opcodes.scala b/src/compiler/scala/tools/nsc/backend/icode/Opcodes.scala deleted file mode 100644 index 351a8e33d3..0000000000 --- a/src/compiler/scala/tools/nsc/backend/icode/Opcodes.scala +++ /dev/null @@ -1,767 +0,0 @@ -/* NSC -- new Scala compiler - * Copyright 2005-2013 LAMP/EPFL - * @author Martin Odersky - */ - -package scala -package tools.nsc -package backend -package icode - -import scala.reflect.internal.util.{Position,NoPosition} - -/* - A pattern match - - // locals - case THIS(clasz) => - case STORE_THIS(kind) => - case LOAD_LOCAL(local) => - case STORE_LOCAL(local) => - case SCOPE_ENTER(lv) => - case SCOPE_EXIT(lv) => - // stack - case LOAD_MODULE(module) => - case LOAD_EXCEPTION(clasz) => - case DROP(kind) => - case DUP(kind) => - // constants - case CONSTANT(const) => - // arithlogic - case CALL_PRIMITIVE(primitive) => - // casts - case IS_INSTANCE(tpe) => - case CHECK_CAST(tpe) => - // objs - case NEW(kind) => - case MONITOR_ENTER() => - case MONITOR_EXIT() => - case BOX(boxType) => - case UNBOX(tpe) => - // flds - case LOAD_FIELD(field, isStatic) => - case STORE_FIELD(field, isStatic) => - // mthds - case CALL_METHOD(method, style) => - // arrays - case LOAD_ARRAY_ITEM(kind) => - case STORE_ARRAY_ITEM(kind) => - case CREATE_ARRAY(elem, dims) => - // jumps - case SWITCH(tags, labels) => - case JUMP(whereto) => - case CJUMP(success, failure, cond, kind) => - case CZJUMP(success, failure, cond, kind) => - // ret - case RETURN(kind) => - case THROW(clasz) => -*/ - - -/** - * The ICode intermediate representation. It is a stack-based - * representation, very close to the JVM and .NET. It uses the - * erased types of Scala and references Symbols to refer named entities - * in the source files. - */ -trait Opcodes { self: ICodes => - import global.{Symbol, NoSymbol, Name, Constant} - - // categories of ICode instructions - final val localsCat = 1 - final val stackCat = 2 - final val constCat = 3 - final val arilogCat = 4 - final val castsCat = 5 - final val objsCat = 6 - final val fldsCat = 7 - final val mthdsCat = 8 - final val arraysCat = 9 - final val jumpsCat = 10 - final val retCat = 11 - - private lazy val ObjectReferenceList = ObjectReference :: Nil - - /** This class represents an instruction of the intermediate code. - * Each case subclass will represent a specific operation. - */ - abstract class Instruction extends Cloneable { - // Vlad: I used these for checking the quality of the implementation, and we should regularly run a build with them - // enabled. But for production these should definitely be disabled, unless we enjoy getting angry emails from Greg :) - //if (!this.isInstanceOf[opcodes.LOAD_EXCEPTION]) - // assert(consumed == consumedTypes.length) - //assert(produced == producedTypes.length) - - def category: Int = 0 // undefined - - /** This abstract method returns the number of used elements on the stack */ - def consumed : Int = 0 - - /** This abstract method returns the number of produced elements on the stack */ - def produced : Int = 0 - - /** This instruction consumes these types from the top of the stack, the first - * element in the list is the deepest element on the stack. - */ - def consumedTypes: List[TypeKind] = Nil - - /** This instruction produces these types on top of the stack. */ - // Vlad: I wonder why we keep producedTypes around -- it looks like an useless thing to have - def producedTypes: List[TypeKind] = Nil - - /** The corresponding position in the source file */ - private var _pos: Position = NoPosition - - def pos: Position = _pos - - def setPos(p: Position): this.type = { - _pos = p - this - } - - /** Clone this instruction. */ - override def clone(): Instruction = - super.clone.asInstanceOf[Instruction] - } - - object opcodes { - /** Loads "this" on top of the stack. - * Stack: ... - * ->: ...:ref - */ - case class THIS(clasz: Symbol) extends Instruction { - /** Returns a string representation of this constant */ - override def toString = "THIS(" + clasz.name + ")" - - override def consumed = 0 - override def produced = 1 - - override def producedTypes = - // we're not allowed to have REFERENCE(Array), but what about compiling the Array class? Well, we use object for it. - if (clasz != global.definitions.ArrayClass) - REFERENCE(clasz) :: Nil - else - ObjectReference :: Nil - - override def category = localsCat - } - - /** Loads a constant on the stack. - * Stack: ... - * ->: ...:constant - */ - case class CONSTANT(constant: Constant) extends Instruction { - override def toString = "CONSTANT(" + constant.escapedStringValue + ")" - override def consumed = 0 - override def produced = 1 - - override def producedTypes = toTypeKind(constant.tpe) :: Nil - - override def category = constCat - } - - /** Loads an element of an array. The array and the index should - * be on top of the stack. - * Stack: ...:array[a](Ref):index(Int) - * ->: ...:element(a) - */ - case class LOAD_ARRAY_ITEM(kind: TypeKind) extends Instruction { - override def consumed = 2 - override def produced = 1 - - override def consumedTypes = ARRAY(kind) :: INT :: Nil - override def producedTypes = kind :: Nil - - override def category = arraysCat - } - - /** Load a local variable on the stack. It can be a method argument. - * Stack: ... - * ->: ...:value - */ - case class LOAD_LOCAL(local: Local) extends Instruction { - override def consumed = 0 - override def produced = 1 - - override def producedTypes = local.kind :: Nil - - override def category = localsCat - } - - /** Load a field on the stack. The object to which it refers should be - * on the stack. - * Stack: ...:ref (assuming isStatic = false) - * ->: ...:value - */ - case class LOAD_FIELD(field: Symbol, isStatic: Boolean) extends Instruction { - /** Returns a string representation of this instruction */ - override def toString(): String = - "LOAD_FIELD " + (if (isStatic) field.fullName else field.toString()) - - override def consumed = if (isStatic) 0 else 1 - override def produced = 1 - - override def consumedTypes = if (isStatic) Nil else REFERENCE(field.owner) :: Nil - override def producedTypes = toTypeKind(field.tpe) :: Nil - - // more precise information about how to load this field - // see #4283 - var hostClass: Symbol = field.owner - def setHostClass(cls: Symbol): this.type = { hostClass = cls; this } - - override def category = fldsCat - } - - case class LOAD_MODULE(module: Symbol) extends Instruction { - assert(module != NoSymbol, "Invalid module symbol") - /** Returns a string representation of this instruction */ - override def toString(): String = "LOAD_MODULE " + module - - override def consumed = 0 - override def produced = 1 - - override def producedTypes = REFERENCE(module) :: Nil - - override def category = stackCat - } - - /** Store a value into an array at a specified index. - * Stack: ...:array[a](Ref):index(Int):value(a) - * ->: ... - */ - case class STORE_ARRAY_ITEM(kind: TypeKind) extends Instruction { - override def consumed = 3 - override def produced = 0 - - override def consumedTypes = ARRAY(kind) :: INT :: kind :: Nil - - override def category = arraysCat - } - - /** Store a value into a local variable. It can be an argument. - * Stack: ...:value - * ->: ... - */ - case class STORE_LOCAL(local: Local) extends Instruction { - override def consumed = 1 - override def produced = 0 - - override def consumedTypes = local.kind :: Nil - - override def category = localsCat - } - - /** Store a value into a field. - * Stack: ...:ref:value (assuming isStatic=false) - * ->: ... - */ - case class STORE_FIELD(field: Symbol, isStatic: Boolean) extends Instruction { - /** Returns a string representation of this instruction */ - override def toString(): String = - "STORE_FIELD "+field + (if (isStatic) " (static)" else " (dynamic)") - - override def consumed = if(isStatic) 1 else 2 - - override def produced = 0 - - override def consumedTypes = - if (isStatic) - toTypeKind(field.tpe) :: Nil - else - REFERENCE(field.owner) :: toTypeKind(field.tpe) :: Nil - - override def category = fldsCat - } - - /** Store a value into the 'this' pointer. - * Stack: ...:ref - * ->: ... - */ - case class STORE_THIS(kind: TypeKind) extends Instruction { - override def consumed = 1 - override def produced = 0 - override def consumedTypes = kind :: Nil - override def category = localsCat - } - - /** Call a primitive function. - * Stack: ...:arg1:arg2:...:argn - * ->: ...:result - */ - case class CALL_PRIMITIVE(primitive: Primitive) extends Instruction { - override def consumed = primitive match { - case Negation(_) => 1 - case Test(_,_, true) => 1 - case Test(_,_, false) => 2 - case Comparison(_,_) => 2 - case Arithmetic(NOT,_) => 1 - case Arithmetic(_,_) => 2 - case Logical(_,_) => 2 - case Shift(_,_) => 2 - case Conversion(_,_) => 1 - case ArrayLength(_) => 1 - case StringConcat(_) => 2 - case StartConcat => 0 - case EndConcat => 1 - } - override def produced = 1 - - override def consumedTypes = primitive match { - case Negation(kind) => kind :: Nil - case Test(_, kind, true) => kind :: Nil - case Test(_, kind, false) => kind :: kind :: Nil - case Comparison(_, kind) => kind :: kind :: Nil - case Arithmetic(NOT, kind) => kind :: Nil - case Arithmetic(_, kind) => kind :: kind :: Nil - case Logical(_, kind) => kind :: kind :: Nil - case Shift(_, kind) => kind :: INT :: Nil - case Conversion(from, _) => from :: Nil - case ArrayLength(kind) => ARRAY(kind) :: Nil - case StringConcat(kind) => ConcatClass :: kind :: Nil - case StartConcat => Nil - case EndConcat => ConcatClass :: Nil - } - - override def producedTypes = primitive match { - case Negation(kind) => kind :: Nil - case Test(_, _, true) => BOOL :: Nil - case Test(_, _, false) => BOOL :: Nil - case Comparison(_, _) => INT :: Nil - case Arithmetic(_, kind) => kind :: Nil - case Logical(_, kind) => kind :: Nil - case Shift(_, kind) => kind :: Nil - case Conversion(_, to) => to :: Nil - case ArrayLength(_) => INT :: Nil - case StringConcat(_) => ConcatClass :: Nil - case StartConcat => ConcatClass :: Nil - case EndConcat => REFERENCE(global.definitions.StringClass) :: Nil - } - - override def category = arilogCat - } - - /** This class represents a CALL_METHOD instruction - * STYLE: dynamic / static(StaticInstance) - * Stack: ...:ref:arg1:arg2:...:argn - * ->: ...:result - * - * STYLE: static(StaticClass) - * Stack: ...:arg1:arg2:...:argn - * ->: ...:result - * - */ - case class CALL_METHOD(method: Symbol, style: InvokeStyle) extends Instruction with ReferenceEquality { - def toShortString = - "CALL_METHOD " + method.name +" ("+style+")" - - /** Returns a string representation of this instruction */ - override def toString(): String = - "CALL_METHOD " + method.fullName +" ("+style+")" - - var hostClass: Symbol = method.owner - def setHostClass(cls: Symbol): this.type = { hostClass = cls; this } - - /** This is specifically for preserving the target native Array type long - * enough that clone() can generate the right call. - */ - var targetTypeKind: TypeKind = UNIT // the default should never be used, so UNIT should fail fast. - def setTargetTypeKind(tk: TypeKind) = targetTypeKind = tk - - private def params = method.info.paramTypes - private def consumesInstance = style match { - case Static(false) => 0 - case _ => 1 - } - - override def consumed = params.length + consumesInstance - override def consumedTypes = { - val args = params map toTypeKind - if (consumesInstance > 0) ObjectReference :: args - else args - } - - private val producedList = toTypeKind(method.info.resultType) match { - case UNIT => Nil - case _ if method.isConstructor => Nil - case kind => kind :: Nil - } - override def produced = producedList.size - override def producedTypes = producedList - - /** object identity is equality for CALL_METHODs. Needed for - * being able to store such instructions into maps, when more - * than one CALL_METHOD to the same method might exist. - */ - - override def category = mthdsCat - } - - /** - * A place holder entry that allows us to parse class files with invoke dynamic - * instructions. Because the compiler doesn't yet really understand the - * behavior of invokeDynamic, this op acts as a poison pill. Any attempt to analyze - * this instruction will cause a failure. The only optimization that - * should ever look at non-Scala generated icode is the inliner, and it - * has been modified to not examine any method with invokeDynamic - * instructions. So if this poison pill ever causes problems then - * there's been a serious misunderstanding - */ - // TODO do the real thing - case class INVOKE_DYNAMIC(poolEntry: Int) extends Instruction { - private def error = sys.error("INVOKE_DYNAMIC is not fully implemented and should not be analyzed") - override def consumed = error - override def produced = error - override def producedTypes = error - override def category = error - } - - case class BOX(boxType: TypeKind) extends Instruction { - assert(boxType.isValueType && (boxType ne UNIT)) // documentation - override def toString(): String = "BOX " + boxType - override def consumed = 1 - override def consumedTypes = boxType :: Nil - override def produced = 1 - override def producedTypes = BOXED(boxType) :: Nil - override def category = objsCat - } - - case class UNBOX(boxType: TypeKind) extends Instruction { - assert(boxType.isValueType && !boxType.isInstanceOf[BOXED] && (boxType ne UNIT)) // documentation - override def toString(): String = "UNBOX " + boxType - override def consumed = 1 - override def consumedTypes = ObjectReferenceList - override def produced = 1 - override def producedTypes = boxType :: Nil - override def category = objsCat - } - - /** Create a new instance of a class through the specified constructor - * Stack: ...:arg1:arg2:...:argn - * ->: ...:ref - */ - case class NEW(kind: REFERENCE) extends Instruction { - /** Returns a string representation of this instruction */ - override def toString(): String = "NEW "+ kind - - override def consumed = 0 - - override def produced = 1 - - override def producedTypes = kind :: Nil - - /** The corresponding constructor call. */ - var init: CALL_METHOD = _ - - override def category = objsCat - } - - - /** This class represents a CREATE_ARRAY instruction - * Stack: ...:size_1:size_2:..:size_n - * ->: ...:arrayref - */ - case class CREATE_ARRAY(elem: TypeKind, dims: Int) extends Instruction { - /** Returns a string representation of this instruction */ - override def toString(): String ="CREATE_ARRAY "+elem + " x " + dims - - override def consumed = dims - - override def consumedTypes = List.fill(dims)(INT) - override def produced = 1 - - override def producedTypes = ARRAY(elem) :: Nil - - override def category = arraysCat - } - - /** This class represents a IS_INSTANCE instruction - * Stack: ...:ref - * ->: ...:result(boolean) - */ - case class IS_INSTANCE(typ: TypeKind) extends Instruction { - /** Returns a string representation of this instruction */ - override def toString(): String ="IS_INSTANCE "+typ - - override def consumed = 1 - override def produced = 1 - override def consumedTypes = ObjectReferenceList - override def producedTypes = BOOL :: Nil - - override def category = castsCat - } - - /** This class represents a CHECK_CAST instruction - * Stack: ...:ref(oldtype) - * ->: ...:ref(typ <=: oldtype) - */ - case class CHECK_CAST(typ: TypeKind) extends Instruction { - /** Returns a string representation of this instruction */ - override def toString(): String ="CHECK_CAST "+typ - - override def consumed = 1 - override def produced = 1 - override def consumedTypes = ObjectReferenceList - override def producedTypes = typ :: Nil - - override def category = castsCat - } - - /** This class represents a SWITCH instruction - * Stack: ...:index(int) - * ->: ...: - * - * The tags array contains one entry per label, each entry consisting of - * an array of ints, any of which will trigger the jump to the corresponding label. - * labels should contain an extra label, which is the 'default' jump. - */ - case class SWITCH(tags: List[List[Int]], labels: List[BasicBlock]) extends Instruction { - /** Returns a string representation of this instruction */ - override def toString(): String ="SWITCH ..." - - override def consumed = 1 - override def produced = 0 - - override def consumedTypes = INT :: Nil - - def flatTagsCount: Int = { var acc = 0; var rest = tags; while(rest.nonEmpty) { acc += rest.head.length; rest = rest.tail }; acc } // a one-liner - - override def category = jumpsCat - } - - /** This class represents a JUMP instruction - * Stack: ... - * ->: ... - */ - case class JUMP(whereto: BasicBlock) extends Instruction { - /** Returns a string representation of this instruction */ - override def toString(): String ="JUMP "+whereto.label - - override def consumed = 0 - override def produced = 0 - - override def category = jumpsCat - } - - /** This class represents a CJUMP instruction - * It compares the two values on the stack with the 'cond' test operator - * Stack: ...:value1:value2 - * ->: ... - */ - case class CJUMP(successBlock: BasicBlock, - failureBlock: BasicBlock, - cond: TestOp, - kind: TypeKind) extends Instruction - { - - /** Returns a string representation of this instruction */ - override def toString(): String = ( - "CJUMP (" + kind + ")" + - cond + " ? "+successBlock.label+" : "+failureBlock.label - ) - - override def consumed = 2 - override def produced = 0 - - override def consumedTypes = kind :: kind :: Nil - - override def category = jumpsCat - } - - /** This class represents a CZJUMP instruction - * It compares the one value on the stack and zero with the 'cond' test operator - * Stack: ...:value: - * ->: ... - */ - case class CZJUMP(successBlock: BasicBlock, - failureBlock: BasicBlock, - cond: TestOp, - kind: TypeKind) extends Instruction { - /** Returns a string representation of this instruction */ - override def toString(): String = ( - "CZJUMP (" + kind + ")" + - cond + " ? "+successBlock.label+" : "+failureBlock.label - ) - - override def consumed = 1 - override def produced = 0 - - override def consumedTypes = kind :: Nil - override def category = jumpsCat - } - - - /** This class represents a RETURN instruction - * Stack: ... - * ->: ... - */ - case class RETURN(kind: TypeKind) extends Instruction { - override def consumed = if (kind == UNIT) 0 else 1 - override def produced = 0 - - override def consumedTypes = if (kind == UNIT) Nil else kind :: Nil - - override def category = retCat - } - - /** This class represents a THROW instruction - * Stack: ...:Throwable(Ref) - * ->: ...: - */ - case class THROW(clasz: Symbol) extends Instruction { - /** PP to ID: We discussed parameterizing LOAD_EXCEPTION but - * not THROW, which came about organically. It seems like the - * right thing, but can you confirm? - */ - override def toString = "THROW(" + clasz.name + ")" - - override def consumed = 1 - override def produced = 0 - - override def consumedTypes = toTypeKind(clasz.tpe) :: Nil - - override def category = retCat - } - - /** This class represents a DROP instruction - * Stack: ...:something - * ->: ... - */ - case class DROP (typ: TypeKind) extends Instruction { - /** Returns a string representation of this instruction */ - override def toString(): String ="DROP "+typ - - override def consumed = 1 - override def produced = 0 - - override def consumedTypes = typ :: Nil - - override def category = stackCat - } - - /** This class represents a DUP instruction - * Stack: ...:something - * ->: ...:something:something - */ - case class DUP (typ: TypeKind) extends Instruction { - override def consumed = 1 - override def produced = 2 - override def consumedTypes = typ :: Nil - override def producedTypes = typ :: typ :: Nil - override def category = stackCat - } - - /** This class represents a MONITOR_ENTER instruction - * Stack: ...:object(ref) - * ->: ...: - */ - case class MONITOR_ENTER() extends Instruction { - /** Returns a string representation of this instruction */ - override def toString(): String ="MONITOR_ENTER" - - override def consumed = 1 - override def produced = 0 - - override def consumedTypes = ObjectReference :: Nil - - override def category = objsCat - } - - /** This class represents a MONITOR_EXIT instruction - * Stack: ...:object(ref) - * ->: ...: - */ - case class MONITOR_EXIT() extends Instruction { - /** Returns a string representation of this instruction */ - override def toString(): String ="MONITOR_EXIT" - - override def consumed = 1 - - override def produced = 0 - - override def consumedTypes = ObjectReference :: Nil - - override def category = objsCat - } - - /** A local variable becomes visible at this point in code. - * Used only for generating precise local variable tables as - * debugging information. - */ - case class SCOPE_ENTER(lv: Local) extends Instruction { - override def toString(): String = "SCOPE_ENTER " + lv - override def consumed = 0 - override def produced = 0 - override def category = localsCat - } - - /** A local variable leaves its scope at this point in code. - * Used only for generating precise local variable tables as - * debugging information. - */ - case class SCOPE_EXIT(lv: Local) extends Instruction { - override def toString(): String = "SCOPE_EXIT " + lv - override def consumed = 0 - override def produced = 0 - override def category = localsCat - } - - /** Fake instruction. It designates the VM who pushes an exception - * on top of the /empty/ stack at the beginning of each exception handler. - * Note: Unlike other instructions, it consumes all elements on the stack! - * then pushes one exception instance. - */ - case class LOAD_EXCEPTION(clasz: Symbol) extends Instruction { - override def consumed = sys.error("LOAD_EXCEPTION does clean the whole stack, no idea how many things it consumes!") - override def produced = 1 - override def producedTypes = REFERENCE(clasz) :: Nil - override def category = stackCat - } - - /** This class represents a method invocation style. */ - sealed abstract class InvokeStyle { - /** Is this a dynamic method call? */ - def isDynamic: Boolean = false - - /** Is this a static method call? */ - def isStatic: Boolean = false - - def isSuper: Boolean = false - - /** Is this an instance method call? */ - def hasInstance: Boolean = true - - /** Returns a string representation of this style. */ - override def toString(): String - } - - /** Virtual calls. - * On JVM, translated to either `invokeinterface` or `invokevirtual`. - */ - case object Dynamic extends InvokeStyle { - override def isDynamic = true - override def toString(): String = "dynamic" - } - - /** - * Special invoke: - * Static(true) is used for calls to private members, ie `invokespecial` on JVM. - * Static(false) is used for calls to class-level instance-less static methods, ie `invokestatic` on JVM. - */ - case class Static(onInstance: Boolean) extends InvokeStyle { - override def isStatic = true - override def hasInstance = onInstance - override def toString(): String = { - if(onInstance) "static-instance" - else "static-class" - } - } - - /** Call through super[mix]. - * On JVM, translated to `invokespecial`. - */ - case class SuperCall(mix: Name) extends InvokeStyle { - override def isSuper = true - override def toString(): String = { "super(" + mix + ")" } - } - } -} diff --git a/src/compiler/scala/tools/nsc/backend/icode/Primitives.scala b/src/compiler/scala/tools/nsc/backend/icode/Primitives.scala deleted file mode 100644 index dd930ba52f..0000000000 --- a/src/compiler/scala/tools/nsc/backend/icode/Primitives.scala +++ /dev/null @@ -1,247 +0,0 @@ -/* NSC -- new scala compiler - * Copyright 2005-2013 LAMP/EPFL - * @author Martin Odersky - */ - - -package scala.tools.nsc -package backend -package icode - -import java.io.PrintWriter - -trait Primitives { self: ICodes => - - /** This class represents a primitive operation. */ - class Primitive { - } - - - // type : (type) => type - // range: type <- { BOOL, Ix, Ux, Rx } - // jvm : {i, l, f, d}neg - case class Negation(kind: TypeKind) extends Primitive - - // type : zero ? (type) => BOOL : (type,type) => BOOL - // range: type <- { BOOL, Ix, Ux, Rx, REF } - // jvm : if{eq, ne, lt, ge, le, gt}, if{null, nonnull} - // if_icmp{eq, ne, lt, ge, le, gt}, if_acmp{eq,ne} - case class Test(op: TestOp, kind: TypeKind, zero: Boolean) extends Primitive - - // type : (type,type) => I4 - // range: type <- { Ix, Ux, Rx } - // jvm : lcmp, {f, d}cmp{l, g} - case class Comparison(op: ComparisonOp, kind: TypeKind) extends Primitive - - // type : (type,type) => type - // range: type <- { Ix, Ux, Rx } - // jvm : {i, l, f, d}{add, sub, mul, div, rem} - case class Arithmetic(op: ArithmeticOp, kind: TypeKind) extends Primitive - - // type : (type,type) => type - // range: type <- { BOOL, Ix, Ux } - // jvm : {i, l}{and, or, xor} - case class Logical(op: LogicalOp, kind: TypeKind) extends Primitive - - // type : (type,I4) => type - // range: type <- { Ix, Ux } - // jvm : {i, l}{shl, ushl, shr} - case class Shift(op: ShiftOp, kind: TypeKind) extends Primitive - - // type : (src) => dst - // range: src,dst <- { Ix, Ux, Rx } - // jvm : i2{l, f, d}, l2{i, f, d}, f2{i, l, d}, d2{i, l, f}, i2{b, c, s} - case class Conversion(src: TypeKind, dst: TypeKind) extends Primitive - - // type : (Array[REF]) => I4 - // range: type <- { BOOL, Ix, Ux, Rx, REF } - // jvm : arraylength - case class ArrayLength(kind: TypeKind) extends Primitive - - // type : (buf,el) => buf - // range: lf,rg <- { BOOL, Ix, Ux, Rx, REF, STR } - // jvm : It should call the appropriate 'append' method on StringBuffer - case class StringConcat(el: TypeKind) extends Primitive - - /** Signals the beginning of a series of concatenations. - * On the JVM platform, it should create a new StringBuffer - */ - case object StartConcat extends Primitive - - /** - * type: (buf) => STR - * jvm : It should turn the StringBuffer into a String. - */ - case object EndConcat extends Primitive - - /** Pretty printer for primitives */ - class PrimitivePrinter(out: PrintWriter) { - def print(s: String): PrimitivePrinter = { - out.print(s) - this - } - } - - /** This class represents a comparison operation. */ - class ComparisonOp { - - /** Returns a string representation of this operation. */ - override def toString(): String = this match { - case CMPL => "CMPL" - case CMP => "CMP" - case CMPG => "CMPG" - case _ => throw new RuntimeException("ComparisonOp unknown case") - } - } - - /** A comparison operation with -1 default for NaNs */ - case object CMPL extends ComparisonOp - - /** A comparison operation with no default for NaNs */ - case object CMP extends ComparisonOp - - /** A comparison operation with +1 default for NaNs */ - case object CMPG extends ComparisonOp - - - /** This class represents a test operation. */ - sealed abstract class TestOp { - - /** Returns the negation of this operation. */ - def negate(): TestOp - - /** Returns a string representation of this operation. */ - override def toString(): String - - /** used only from GenASM */ - def opcodeIF(): Int - - /** used only from GenASM */ - def opcodeIFICMP(): Int - - } - - /** An equality test */ - case object EQ extends TestOp { - def negate() = NE - override def toString() = "EQ" - override def opcodeIF() = scala.tools.asm.Opcodes.IFEQ - override def opcodeIFICMP() = scala.tools.asm.Opcodes.IF_ICMPEQ - } - - /** A non-equality test */ - case object NE extends TestOp { - def negate() = EQ - override def toString() = "NE" - override def opcodeIF() = scala.tools.asm.Opcodes.IFNE - override def opcodeIFICMP() = scala.tools.asm.Opcodes.IF_ICMPNE - } - - /** A less-than test */ - case object LT extends TestOp { - def negate() = GE - override def toString() = "LT" - override def opcodeIF() = scala.tools.asm.Opcodes.IFLT - override def opcodeIFICMP() = scala.tools.asm.Opcodes.IF_ICMPLT - } - - /** A greater-than-or-equal test */ - case object GE extends TestOp { - def negate() = LT - override def toString() = "GE" - override def opcodeIF() = scala.tools.asm.Opcodes.IFGE - override def opcodeIFICMP() = scala.tools.asm.Opcodes.IF_ICMPGE - } - - /** A less-than-or-equal test */ - case object LE extends TestOp { - def negate() = GT - override def toString() = "LE" - override def opcodeIF() = scala.tools.asm.Opcodes.IFLE - override def opcodeIFICMP() = scala.tools.asm.Opcodes.IF_ICMPLE - } - - /** A greater-than test */ - case object GT extends TestOp { - def negate() = LE - override def toString() = "GT" - override def opcodeIF() = scala.tools.asm.Opcodes.IFGT - override def opcodeIFICMP() = scala.tools.asm.Opcodes.IF_ICMPGT - } - - /** This class represents an arithmetic operation. */ - class ArithmeticOp { - - /** Returns a string representation of this operation. */ - override def toString(): String = this match { - case ADD => "ADD" - case SUB => "SUB" - case MUL => "MUL" - case DIV => "DIV" - case REM => "REM" - case NOT => "NOT" - case _ => throw new RuntimeException("ArithmeticOp unknown case") - } - } - - /** An arithmetic addition operation */ - case object ADD extends ArithmeticOp - - /** An arithmetic subtraction operation */ - case object SUB extends ArithmeticOp - - /** An arithmetic multiplication operation */ - case object MUL extends ArithmeticOp - - /** An arithmetic division operation */ - case object DIV extends ArithmeticOp - - /** An arithmetic remainder operation */ - case object REM extends ArithmeticOp - - /** Bitwise negation. */ - case object NOT extends ArithmeticOp - - /** This class represents a shift operation. */ - class ShiftOp { - - /** Returns a string representation of this operation. */ - override def toString(): String = this match { - case LSL => "LSL" - case ASR => "ASR" - case LSR => "LSR" - case _ => throw new RuntimeException("ShiftOp unknown case") - } - } - - /** A logical shift to the left */ - case object LSL extends ShiftOp - - /** An arithmetic shift to the right */ - case object ASR extends ShiftOp - - /** A logical shift to the right */ - case object LSR extends ShiftOp - - /** This class represents a logical operation. */ - class LogicalOp { - - /** Returns a string representation of this operation. */ - override def toString(): String = this match { - case AND => "AND" - case OR => "OR" - case XOR => "XOR" - case _ => throw new RuntimeException("LogicalOp unknown case") - } - } - - /** A bitwise AND operation */ - case object AND extends LogicalOp - - /** A bitwise OR operation */ - case object OR extends LogicalOp - - /** A bitwise XOR operation */ - case object XOR extends LogicalOp -} - diff --git a/src/compiler/scala/tools/nsc/backend/icode/Printers.scala b/src/compiler/scala/tools/nsc/backend/icode/Printers.scala deleted file mode 100644 index 1fe33f78e7..0000000000 --- a/src/compiler/scala/tools/nsc/backend/icode/Printers.scala +++ /dev/null @@ -1,126 +0,0 @@ -/* NSC -- new scala compiler - * Copyright 2005-2013 LAMP/EPFL - * @author Martin Odersky - */ - -package scala.tools.nsc -package backend -package icode - -import java.io.PrintWriter - -trait Printers { self: ICodes => - import global._ - - class TextPrinter(writer: PrintWriter, lin: Linearizer) { - private var margin = 0 - private var out = writer - - final val TAB = 2 - - def setWriter(w: PrintWriter) { out = w } - - def indent() { margin += TAB } - def undent() { margin -= TAB } - - def print(s: String) { out.print(s) } - def print(o: Any) { print(o.toString()) } - - def println(s: String) { - print(s) - println() - } - - def println() { - out.println() - var i = 0 - while (i < margin) { - print(" ") - i += 1 - } - } - - def printList[A](l: List[A], sep: String): Unit = l match { - case Nil => - case x :: Nil => print(x) - case x :: xs => print(x); print(sep); printList(xs, sep) - } - - def printList[A](pr: A => Unit)(l: List[A], sep: String): Unit = l match { - case Nil => - case x :: Nil => pr(x) - case x :: xs => pr(x); print(sep); printList(pr)(xs, sep) - } - - def printClass(cls: IClass) { - print(cls.symbol.toString()); print(" extends ") - printList(cls.symbol.info.parents, ", ") - indent(); println(" {") - println("// fields:") - cls.fields.foreach(printField); println() - println("// methods") - cls.methods.foreach(printMethod) - undent(); println() - println("}") - } - - def printField(f: IField) { - print(f.symbol.keyString); print(" ") - print(f.symbol.nameString); print(": ") - println(f.symbol.info.toString()) - } - - def printMethod(m: IMethod) { - print("def "); print(m.symbol.name) - print("("); printList(printParam)(m.params, ", "); print(")") - print(": "); print(m.symbol.info.resultType) - - if (!m.isAbstractMethod) { - println(" {") - println("locals: " + m.locals.mkString("", ", ", "")) - println("startBlock: " + m.startBlock) - println("blocks: " + m.code.blocks.mkString("[", ",", "]")) - println() - lin.linearize(m) foreach printBlock - println("}") - - indent(); println("Exception handlers: ") - m.exh foreach printExceptionHandler - - undent(); println() - } else - println() - } - - def printParam(p: Local) { - print(p.sym.name); print(": "); print(p.sym.info) - print(" ("); print(p.kind); print(")") - } - - def printExceptionHandler(e: ExceptionHandler) { - indent() - println("catch (" + e.cls.simpleName + ") in " + e.covered.toSeq.sortBy(_.label) + " starting at: " + e.startBlock) - println("consisting of blocks: " + e.blocks) - undent() - println("with finalizer: " + e.finalizer) - // linearizer.linearize(e.startBlock) foreach printBlock; - } - - def printBlock(bb: BasicBlock) { - print(bb.label) - if (bb.loopHeader) print("[loop header]") - print(": ") - if (settings.debug) print("pred: " + bb.predecessors + " succs: " + bb.successors + " flags: " + bb.flagsString) - indent(); println() - bb.toList foreach printInstruction - undent(); println() - } - - def printInstruction(i: Instruction) { -// if (settings.Xdce.value) -// print(if (i.useful) " " else " * "); - if (i.pos.isDefined) print(i.pos.line.toString + "\t") else print("?\t") - println(i.toString()) - } - } -} diff --git a/src/compiler/scala/tools/nsc/backend/icode/Repository.scala b/src/compiler/scala/tools/nsc/backend/icode/Repository.scala deleted file mode 100644 index 10d57df4a3..0000000000 --- a/src/compiler/scala/tools/nsc/backend/icode/Repository.scala +++ /dev/null @@ -1,47 +0,0 @@ -/* NSC -- new Scala compiler - * Copyright 2005-2013 LAMP/EPFL - * @author Martin Odersky - */ - - -package scala.tools.nsc -package backend -package icode - -import scala.collection._ - -/** - * @author Iulian Dragos - */ -trait Repository { - val global: Global - import global._ - import icodes._ - - val loaded: mutable.Map[Symbol, IClass] = perRunCaches.newMap() - - /** Is the given class available as icode? */ - def available(sym: Symbol) = classes.contains(sym) || loaded.contains(sym) - - /** The icode of the given class, if available */ - def icode(sym: Symbol): Option[IClass] = (classes get sym) orElse (loaded get sym) - - /** Load bytecode for given symbol. */ - def load(sym: Symbol): Boolean = { - try { - val (c1, c2) = icodeReader.readClass(sym) - - assert(c1.symbol == sym || c2.symbol == sym, "c1.symbol = %s, c2.symbol = %s, sym = %s".format(c1.symbol, c2.symbol, sym)) - loaded += (c1.symbol -> c1) - loaded += (c2.symbol -> c2) - - true - } catch { - case e: Throwable => // possible exceptions are MissingRequirementError, IOException and TypeError -> no better common supertype - log("Failed to load %s. [%s]".format(sym.fullName, e.getMessage)) - if (settings.debug) { e.printStackTrace } - - false - } - } -} diff --git a/src/compiler/scala/tools/nsc/backend/icode/TypeKinds.scala b/src/compiler/scala/tools/nsc/backend/icode/TypeKinds.scala deleted file mode 100644 index a6d0d3b9fa..0000000000 --- a/src/compiler/scala/tools/nsc/backend/icode/TypeKinds.scala +++ /dev/null @@ -1,438 +0,0 @@ -/* NSC -- new Scala compiler - * Copyright 2005-2013 LAMP/EPFL - * @author Martin Odersky - */ - -package scala.tools.nsc -package backend -package icode - -/* A type case - - case UNIT => - case BOOL => - case BYTE => - case SHORT => - case CHAR => - case INT => - case LONG => - case FLOAT => - case DOUBLE => - case REFERENCE(cls) => - case ARRAY(elem) => - -*/ - -trait TypeKinds { self: ICodes => - import global._ - import definitions.{ ArrayClass, AnyRefClass, ObjectClass, NullClass, NothingClass, arrayType } - - /** A map from scala primitive Types to ICode TypeKinds */ - lazy val primitiveTypeMap: Map[Symbol, TypeKind] = { - import definitions._ - Map( - UnitClass -> UNIT, - BooleanClass -> BOOL, - CharClass -> CHAR, - ByteClass -> BYTE, - ShortClass -> SHORT, - IntClass -> INT, - LongClass -> LONG, - FloatClass -> FLOAT, - DoubleClass -> DOUBLE - ) - } - /** Reverse map for toType */ - private lazy val reversePrimitiveMap: Map[TypeKind, Symbol] = - (primitiveTypeMap map (_.swap)).toMap - - /** This class represents a type kind. Type kinds - * represent the types that the VM know (or the ICode - * view of what VMs know). - */ - sealed abstract class TypeKind { - def maxType(other: TypeKind): TypeKind - - def toType: Type = reversePrimitiveMap get this map (_.tpe) getOrElse { - this match { - case REFERENCE(cls) => cls.tpe_* - case ARRAY(elem) => arrayType(elem.toType) - case _ => abort("Unknown type kind.") - } - } - - def isReferenceType = false - def isArrayType = false - def isValueType = false - def isBoxedType = false - final def isRefOrArrayType = isReferenceType || isArrayType - final def isNothingType = this == NothingReference - final def isNullType = this == NullReference - final def isInterfaceType = this match { - case REFERENCE(cls) if cls.isInterface || cls.isTrait => true - case _ => false - } - - /** On the JVM, - * BOOL, BYTE, CHAR, SHORT, and INT - * are like Ints for the purposes of calculating the lub. - */ - def isIntSizedType: Boolean = false - - /** On the JVM, similar to isIntSizedType except that BOOL isn't integral while LONG is. */ - def isIntegralType: Boolean = false - - /** On the JVM, FLOAT and DOUBLE. */ - def isRealType: Boolean = false - - final def isNumericType: Boolean = isIntegralType | isRealType - - /** Simple subtyping check */ - def <:<(other: TypeKind): Boolean - - /** - * this is directly assignable to other if no coercion or - * casting is needed to convert this to other. It's a distinct - * relationship from <:< because on the JVM, BOOL, BYTE, CHAR, - * SHORT need no coercion to INT even though JVM arrays - * are covariant, ARRAY[SHORT] is not a subtype of ARRAY[INT] - */ - final def isAssignabledTo(other: TypeKind): Boolean = other match { - case INT => this.isIntSizedType - case _ => this <:< other - } - - /** Is this type a category 2 type in JVM terms? (ie, is it LONG or DOUBLE?) */ - def isWideType: Boolean = false - - /** The number of dimensions for array types. */ - def dimensions: Int = 0 - - protected def uncomparable(thisKind: String, other: TypeKind): Nothing = - abort("Uncomparable type kinds: " + thisKind + " with " + other) - - protected def uncomparable(other: TypeKind): Nothing = - uncomparable(this.toString, other) - } - - sealed abstract class ValueTypeKind extends TypeKind { - override def isValueType = true - override def toString = { - this.getClass.getName stripSuffix "$" dropWhile (_ != '$') drop 1 - } - def <:<(other: TypeKind): Boolean = this eq other - } - - /** - * The least upper bound of two typekinds. They have to be either - * REFERENCE or ARRAY kinds. - * - * The lub is based on the lub of scala types. - */ - def lub(a: TypeKind, b: TypeKind): TypeKind = { - /* The compiler's lub calculation does not order classes before traits. - * This is apparently not wrong but it is inconvenient, and causes the - * icode checker to choke when things don't match up. My attempts to - * alter the calculation at the compiler level were failures, so in the - * interests of a working icode checker I'm making the adjustment here. - * - * Example where we'd like a different answer: - * - * abstract class Tom - * case object Bob extends Tom - * case object Harry extends Tom - * List(Bob, Harry) // compiler calculates "Product with Tom" rather than "Tom with Product" - * - * Here we make the adjustment by rewinding to a pre-erasure state and - * sifting through the parents for a class type. - */ - def lub0(tk1: TypeKind, tk2: TypeKind): Type = enteringUncurry { - val tp = global.lub(List(tk1.toType, tk2.toType)) - val (front, rest) = tp.parents span (_.typeSymbol.isTrait) - - if (front.isEmpty || rest.isEmpty || rest.head.typeSymbol == ObjectClass) tp - else rest.head - } - - def isIntLub = ( - (a == INT && b.isIntSizedType) || - (b == INT && a.isIntSizedType) - ) - - if (a == b) a - else if (a.isNothingType) b - else if (b.isNothingType) a - else if (a.isBoxedType || b.isBoxedType) AnyRefReference // we should do better - else if (isIntLub) INT - else if (a.isRefOrArrayType && b.isRefOrArrayType) { - if (a.isNullType) b - else if (b.isNullType) a - else toTypeKind(lub0(a, b)) - } - else throw new CheckerException("Incompatible types: " + a + " with " + b) - } - - /** The unit value */ - case object UNIT extends ValueTypeKind { - def maxType(other: TypeKind) = other match { - case UNIT | REFERENCE(NothingClass) => UNIT - case _ => uncomparable(other) - } - } - - /** A boolean value */ - case object BOOL extends ValueTypeKind { - override def isIntSizedType = true - def maxType(other: TypeKind) = other match { - case BOOL | REFERENCE(NothingClass) => BOOL - case _ => uncomparable(other) - } - } - - /** Note that the max of Char/Byte and Char/Short is Int, because - * neither strictly encloses the other due to unsignedness. - * See ticket #2087 for a consequence. - */ - - /** A 1-byte signed integer */ - case object BYTE extends ValueTypeKind { - override def isIntSizedType = true - override def isIntegralType = true - def maxType(other: TypeKind) = { - if (other == BYTE || other.isNothingType) BYTE - else if (other == CHAR) INT - else if (other.isNumericType) other - else uncomparable(other) - } - } - - /** A 2-byte signed integer */ - case object SHORT extends ValueTypeKind { - override def isIntSizedType = true - override def isIntegralType = true - override def maxType(other: TypeKind) = other match { - case BYTE | SHORT | REFERENCE(NothingClass) => SHORT - case CHAR => INT - case INT | LONG | FLOAT | DOUBLE => other - case _ => uncomparable(other) - } - } - - /** A 2-byte UNSIGNED integer */ - case object CHAR extends ValueTypeKind { - override def isIntSizedType = true - override def isIntegralType = true - override def maxType(other: TypeKind) = other match { - case CHAR | REFERENCE(NothingClass) => CHAR - case BYTE | SHORT => INT - case INT | LONG | FLOAT | DOUBLE => other - case _ => uncomparable(other) - } - } - - /** A 4-byte signed integer */ - case object INT extends ValueTypeKind { - override def isIntSizedType = true - override def isIntegralType = true - override def maxType(other: TypeKind) = other match { - case BYTE | SHORT | CHAR | INT | REFERENCE(NothingClass) => INT - case LONG | FLOAT | DOUBLE => other - case _ => uncomparable(other) - } - } - - /** An 8-byte signed integer */ - case object LONG extends ValueTypeKind { - override def isIntegralType = true - override def isWideType = true - override def maxType(other: TypeKind): TypeKind = - if (other.isIntegralType || other.isNothingType) LONG - else if (other.isRealType) DOUBLE - else uncomparable(other) - } - - /** A 4-byte floating point number */ - case object FLOAT extends ValueTypeKind { - override def isRealType = true - override def maxType(other: TypeKind): TypeKind = - if (other == DOUBLE) DOUBLE - else if (other.isNumericType || other.isNothingType) FLOAT - else uncomparable(other) - } - - /** An 8-byte floating point number */ - case object DOUBLE extends ValueTypeKind { - override def isRealType = true - override def isWideType = true - override def maxType(other: TypeKind): TypeKind = - if (other.isNumericType || other.isNothingType) DOUBLE - else uncomparable(other) - } - - /** A class type. */ - final case class REFERENCE(cls: Symbol) extends TypeKind { - override def toString = "REF(" + cls + ")" - assert(cls ne null, - "REFERENCE to null class symbol.") - assert(cls != ArrayClass, - "REFERENCE to Array is not allowed, should be ARRAY[..] instead") - assert(cls != NoSymbol, - "REFERENCE to NoSymbol not allowed!") - - /** - * Approximate `lub`. The common type of two references is - * always AnyRef. For 'real' least upper bound wrt to subclassing - * use method 'lub'. - */ - override def maxType(other: TypeKind) = other match { - case REFERENCE(_) | ARRAY(_) => AnyRefReference - case _ => uncomparable("REFERENCE", other) - } - - /** Checks subtyping relationship. */ - def <:<(other: TypeKind) = isNothingType || (other match { - case REFERENCE(cls2) => cls.tpe <:< cls2.tpe - case ARRAY(_) => cls == NullClass - case _ => false - }) - override def isReferenceType = true - } - - def ArrayN(elem: TypeKind, dims: Int): ARRAY = { - assert(dims > 0) - if (dims == 1) ARRAY(elem) - else ARRAY(ArrayN(elem, dims - 1)) - } - - final case class ARRAY(elem: TypeKind) extends TypeKind { - override def toString = "ARRAY[" + elem + "]" - override def isArrayType = true - override def dimensions = 1 + elem.dimensions - - /** The ultimate element type of this array. */ - def elementKind: TypeKind = elem match { - case a @ ARRAY(_) => a.elementKind - case k => k - } - - /** - * Approximate `lub`. The common type of two references is - * always AnyRef. For 'real' least upper bound wrt to subclassing - * use method 'lub'. - */ - override def maxType(other: TypeKind) = other match { - case ARRAY(elem2) if elem == elem2 => ARRAY(elem) - case ARRAY(_) | REFERENCE(_) => AnyRefReference - case _ => uncomparable("ARRAY", other) - } - - /** Array subtyping is covariant, as in Java. Necessary for checking - * code that interacts with Java. */ - def <:<(other: TypeKind) = other match { - case ARRAY(elem2) => elem <:< elem2 - case REFERENCE(AnyRefClass | ObjectClass) => true // TODO: platform dependent! - case _ => false - } - } - - /** A boxed value. */ - case class BOXED(kind: TypeKind) extends TypeKind { - override def isBoxedType = true - - override def maxType(other: TypeKind) = other match { - case BOXED(`kind`) => this - case REFERENCE(_) | ARRAY(_) | BOXED(_) => AnyRefReference - case _ => uncomparable("BOXED", other) - } - - /** Checks subtyping relationship. */ - def <:<(other: TypeKind) = other match { - case BOXED(`kind`) => true - case REFERENCE(AnyRefClass | ObjectClass) => true // TODO: platform dependent! - case _ => false - } - } - - /** - * Dummy TypeKind to represent the ConcatClass in a platform-independent - * way. For JVM it would have been a REFERENCE to 'StringBuffer'. - */ - case object ConcatClass extends TypeKind { - override def toString = "ConcatClass" - def <:<(other: TypeKind): Boolean = this eq other - - /** - * Approximate `lub`. The common type of two references is - * always AnyRef. For 'real' least upper bound wrt to subclassing - * use method 'lub'. - */ - override def maxType(other: TypeKind) = other match { - case REFERENCE(_) => AnyRefReference - case _ => uncomparable(other) - } - } - - ////////////////// Conversions ////////////////////////////// - - /** Return the TypeKind of the given type - * - * Call to dealiasWiden fixes #3003 (follow type aliases). Otherwise, - * arrayOrClassType below would return ObjectReference. - */ - def toTypeKind(t: Type): TypeKind = t.dealiasWiden match { - case ThisType(ArrayClass) => ObjectReference - case ThisType(sym) => REFERENCE(sym) - case SingleType(_, sym) => primitiveOrRefType(sym) - case ConstantType(_) => toTypeKind(t.underlying) - case TypeRef(_, sym, args) => primitiveOrClassType(sym, args) - case ClassInfoType(_, _, ArrayClass) => abort("ClassInfoType to ArrayClass!") - case ClassInfoType(_, _, sym) => primitiveOrRefType(sym) - - // !!! Iulian says types which make no sense after erasure should not reach here, - // which includes the ExistentialType, AnnotatedType, RefinedType. I don't know - // if the first two cases exist because they do or as a defensive measure, but - // at the time I added it, RefinedTypes were indeed reaching here. - case ExistentialType(_, t) => toTypeKind(t) - case AnnotatedType(_, t) => toTypeKind(t) - case RefinedType(parents, _) => parents map toTypeKind reduceLeft lub - // For sure WildcardTypes shouldn't reach here either, but when - // debugging such situations this may come in handy. - // case WildcardType => REFERENCE(ObjectClass) - case norm => abort( - "Unknown type: %s, %s [%s, %s] TypeRef? %s".format( - t, norm, t.getClass, norm.getClass, t.isInstanceOf[TypeRef] - ) - ) - } - - /** Return the type kind of a class, possibly an array type. - */ - private def arrayOrClassType(sym: Symbol, targs: List[Type]) = sym match { - case ArrayClass => ARRAY(toTypeKind(targs.head)) - case _ if sym.isClass => newReference(sym) - case _ => - assert(sym.isType, sym) // it must be compiling Array[a] - ObjectReference - } - /** Interfaces have to be handled delicately to avoid introducing - * spurious errors, but if we treat them all as AnyRef we lose too - * much information. - */ - private def newReference(sym: Symbol): TypeKind = { - // Can't call .toInterface (at this phase) or we trip an assertion. - // See PackratParser#grow for a method which fails with an apparent mismatch - // between "object PackratParsers$class" and "trait PackratParsers" - if (sym.isImplClass) { - // pos/spec-List.scala is the sole failure if we don't check for NoSymbol - val traitSym = sym.owner.info.decl(tpnme.interfaceName(sym.name)) - if (traitSym != NoSymbol) - return REFERENCE(traitSym) - } - REFERENCE(sym) - } - - private def primitiveOrRefType(sym: Symbol) = - primitiveTypeMap.getOrElse(sym, newReference(sym)) - private def primitiveOrClassType(sym: Symbol, targs: List[Type]) = - primitiveTypeMap.getOrElse(sym, arrayOrClassType(sym, targs)) -} diff --git a/src/compiler/scala/tools/nsc/backend/icode/TypeStacks.scala b/src/compiler/scala/tools/nsc/backend/icode/TypeStacks.scala deleted file mode 100644 index 57d51dad49..0000000000 --- a/src/compiler/scala/tools/nsc/backend/icode/TypeStacks.scala +++ /dev/null @@ -1,82 +0,0 @@ -/* NSC -- new Scala compiler - * Copyright 2005-2013 LAMP/EPFL - * @author Martin Odersky - */ - -package scala.tools.nsc -package backend -package icode - -/** This trait ... - * - * @author Iulian Dragos - * @version 1.0 - */ -trait TypeStacks { - self: ICodes => - - /* This class simulates the type of the operand - * stack of the ICode. - */ - type Rep = List[TypeKind] - - class TypeStack(var types: Rep) { - if (types.nonEmpty) - checkerDebug("Created " + this) - - def this() = this(Nil) - def this(that: TypeStack) = this(that.types) - - def length: Int = types.length - def isEmpty = length == 0 - def nonEmpty = length != 0 - - /** Push a type on the type stack. UNITs are ignored. */ - def push(t: TypeKind) = { - if (t != UNIT) - types = t :: types - } - - def head: TypeKind = types.head - - /** Removes the value on top of the stack, and returns it. It assumes - * the stack contains at least one element. - */ - def pop: TypeKind = { - val t = types.head - types = types.tail - t - } - - /** Return the topmost two values on the stack. It assumes the stack - * is large enough. Topmost element first. - */ - def pop2: (TypeKind, TypeKind) = (pop, pop) - - /** Return the topmost three values on the stack. It assumes the stack - * is large enough. Topmost element first. - */ - def pop3: (TypeKind, TypeKind, TypeKind) = (pop, pop, pop) - - /** Drop the first n elements of the stack. */ - def pop(n: Int): List[TypeKind] = { - val prefix = types.take(n) - types = types.drop(n) - prefix - } - - def apply(n: Int): TypeKind = types(n) - - /* This method returns a String representation of the stack */ - override def toString() = - if (types.isEmpty) "[]" - else types.mkString("[", " ", "]") - - override def hashCode() = types.hashCode() - override def equals(other: Any): Boolean = other match { - case x: TypeStack => x.types == types - case _ => false - } - } - -} diff --git a/src/compiler/scala/tools/nsc/backend/icode/analysis/CopyPropagation.scala b/src/compiler/scala/tools/nsc/backend/icode/analysis/CopyPropagation.scala deleted file mode 100644 index 9d48d7a0d3..0000000000 --- a/src/compiler/scala/tools/nsc/backend/icode/analysis/CopyPropagation.scala +++ /dev/null @@ -1,553 +0,0 @@ -/* NSC -- new Scala compiler - * Copyright 2005-2013 LAMP/EPFL - * @author Martin Odersky - */ - -package scala -package tools.nsc -package backend.icode.analysis - -import scala.collection.{ mutable, immutable } - -/** A modified copy-propagation like analysis. It - * is augmented with a record-like value which is used - * to represent closures. - * - * @author Iulian Dragos - */ -abstract class CopyPropagation { - val global: Global - import global._ - import icodes._ - - /** Locations can be local variables, this, and fields. */ - abstract sealed class Location - case class LocalVar(l: Local) extends Location - case class Field(r: Record, sym: Symbol) extends Location - case object This extends Location - - /** Values that can be on the stack. */ - sealed abstract class Value { } - case class Record(cls: Symbol, bindings: mutable.Map[Symbol, Value]) extends Value { } - /** The value of some location in memory. */ - case class Deref(l: Location) extends Value - - /** The boxed value of some location. */ - case class Boxed(l: Location) extends Value - - /** The constant value c. */ - case class Const(c: Constant) extends Value - - /** Unknown. */ - case object Unknown extends Value - - /** The bottom record. */ - object AllRecords extends Record(NoSymbol, mutable.HashMap[Symbol, Value]()) - - /** The lattice for this analysis. */ - object copyLattice extends SemiLattice { - type Bindings = mutable.Map[Location, Value] - - def emptyBinding = mutable.HashMap[Location, Value]() - - class State(val bindings: Bindings, var stack: List[Value]) { - - override def hashCode = bindings.hashCode + stack.hashCode - /* comparison with bottom is reference equality! */ - override def equals(that: Any): Boolean = that match { - case x: State => - if ((this eq bottom) || (this eq top) || (x eq bottom) || (x eq top)) this eq x - else bindings == x.bindings && stack == x.stack - case _ => - false - } - - /* Return an alias for the given local. It returns the last - * local in the chain of aliased locals. Cycles are not allowed - * to exist (by construction). - */ - def getAlias(l: Local): Local = { - var target = l - var stop = false - - while (bindings.isDefinedAt(LocalVar(target)) && !stop) { - bindings(LocalVar(target)) match { - case Deref(LocalVar(t)) => target = t - case _ => stop = true - } - } - target - } - - /* Return the value bound to the given local. */ - def getBinding(l: Local): Value = { - def loop(lv: Local): Option[Value] = (bindings get LocalVar(lv)) match { - case Some(Deref(LocalVar(t))) => loop(t) - case x => x - } - loop(l) getOrElse Deref(LocalVar(l)) - } - - /** Return a local which contains the same value as this field, if any. - * If the field holds a reference to a local, the returned value is the - * binding of that local. - */ - def getFieldValue(r: Record, f: Symbol): Option[Value] = r.bindings get f map { - case Deref(LocalVar(l)) => getBinding(l) - case target @ Deref(Field(r1, f1)) => getFieldValue(r1, f1) getOrElse target - case target => target - } - - /** The same as getFieldValue, but never returns Record/Field values. Use - * this when you want to find a replacement for a field value (either a local, - * or a constant/this value). - */ - def getFieldNonRecordValue(r: Record, f: Symbol): Option[Value] = { - assert(r.bindings contains f, "Record " + r + " does not contain a field " + f) - - r.bindings(f) match { - case Deref(LocalVar(l)) => - val alias = getAlias(l) - val derefAlias = Deref(LocalVar(alias)) - - Some(getBinding(alias) match { - case Record(_, _) => derefAlias - case Deref(Field(r1, f1)) => getFieldNonRecordValue(r1, f1) getOrElse derefAlias - case Boxed(_) => derefAlias - case v => v - }) - case Deref(Field(r1, f1)) => getFieldNonRecordValue(r1, f1) - case target @ Deref(This) => Some(target) - case target @ Const(k) => Some(target) - case _ => None - } - } - - override def toString(): String = - "\nBindings: " + bindings + "\nStack: " + stack - - def dup: State = { - val b: Bindings = mutable.HashMap() - b ++= bindings - new State(b, stack) - } - } - - type Elem = State - - val top = new State(emptyBinding, Nil) - val bottom = new State(emptyBinding, Nil) - - val exceptionHandlerStack = Unknown :: Nil - - def lub2(exceptional: Boolean)(a: Elem, b: Elem): Elem = { - if (a eq bottom) b - else if (b eq bottom) a - else if (a == b) a - else { - //assert(!(a.stack eq exceptionHandlerStack) && !(b.stack eq exceptionHandlerStack)) - val resStack = - if (exceptional) exceptionHandlerStack - else { -// if (a.stack.length != b.stack.length) -// throw new LubException(a, b, "Invalid stacks in states: "); - (a.stack, b.stack).zipped map { (v1, v2) => - if (v1 == v2) v1 else Unknown - } - } - -/* if (a.stack.length != b.stack.length) - throw new LubException(a, b, "Invalid stacks in states: "); - val resStack = List.map2(a.stack, b.stack) { (v1, v2) => - if (v1 == v2) v1 else Unknown - } - */ - val resBindings = mutable.HashMap[Location, Value]() - - for ((k, v) <- a.bindings if b.bindings.isDefinedAt(k) && v == b.bindings(k)) - resBindings += (k -> v) - new State(resBindings, resStack) - } - } - } - - final class CopyAnalysis extends DataFlowAnalysis[copyLattice.type] { - type P = BasicBlock - val lattice = copyLattice - - var method: IMethod = _ - - def init(m: IMethod) { - this.method = m - - init { - worklist += m.startBlock - worklist ++= (m.exh map (_.startBlock)) - m foreachBlock { b => - in(b) = lattice.bottom - out(b) = lattice.bottom - assert(out.contains(b), out) - debuglog("CopyAnalysis added point: " + b) - } - m.exh foreach { e => - in(e.startBlock) = new copyLattice.State(copyLattice.emptyBinding, copyLattice.exceptionHandlerStack) - } - - // first block is special: it's not bottom, but a precisely defined state with no bindings - in(m.startBlock) = new lattice.State(lattice.emptyBinding, Nil) - } - } - - override def run() { - forwardAnalysis(blockTransfer) - if (settings.debug) { - linearizer.linearize(method).foreach(b => if (b != method.startBlock) - assert(in(b) != lattice.bottom, - "Block " + b + " in " + this.method + " has input equal to bottom -- not visited?")) - } - } - - def blockTransfer(b: BasicBlock, in: lattice.Elem): lattice.Elem = - b.iterator.foldLeft(in)(interpret) - - import opcodes._ - - private def retain[A, B](map: mutable.Map[A, B])(p: (A, B) => Boolean) = { - for ((k, v) <- map ; if !p(k, v)) map -= k - map - } - - /** Abstract interpretation for one instruction. */ - def interpret(in: copyLattice.Elem, i: Instruction): copyLattice.Elem = { - var out = in.dup - debuglog("- " + i + "\nin: " + in + "\n") - - i match { - case THIS(_) => - out.stack = Deref(This) :: out.stack - - case CONSTANT(k) => - if (k.tag != UnitTag) - out.stack = Const(k) :: out.stack - - case LOAD_ARRAY_ITEM(_) => - out.stack = (Unknown :: out.stack.drop(2)) - - case LOAD_LOCAL(local) => - out.stack = Deref(LocalVar(local)) :: out.stack - - case LOAD_FIELD(field, isStatic) => - if (isStatic) - out.stack = Unknown :: out.stack; /* ignore static fields */ - else { - val v1 = in.stack match { - case (r @ Record(cls, bindings)) :: xs => - Deref(Field(r, field)) - - case Deref(LocalVar(l)) :: _ => - in.getBinding(l) match { - case r @ Record(cls, bindings) => Deref(Field(r, field)) - case _ => Unknown - } - - case Deref(Field(r, f)) :: _ => - val fld = in.getFieldValue(r, f) - fld match { - case Some(r @ Record(cls, bindings)) if bindings.isDefinedAt(f) => - in.getFieldValue(r, f).getOrElse(Unknown) - case _ => Unknown - } - - case _ => Unknown - } - out.stack = v1 :: out.stack.drop(1) - } - - case LOAD_MODULE(module) => - out.stack = Unknown :: out.stack - - case STORE_ARRAY_ITEM(kind) => - out.stack = out.stack.drop(3) - - case STORE_LOCAL(local) => - cleanReferencesTo(out, LocalVar(local)) - in.stack match { - case Unknown :: xs => () - case v :: vs => - v match { - case Deref(LocalVar(other)) => - if (other != local) - out.bindings += (LocalVar(local) -> v) - case _ => - out.bindings += (LocalVar(local) -> v) - } - case Nil => - sys.error("Incorrect icode in " + method + ". Expecting something on the stack.") - } - out.stack = out.stack drop 1 - - case STORE_THIS(_) => - cleanReferencesTo(out, This) - out.stack = out.stack drop 1 - - case STORE_FIELD(field, isStatic) => - if (isStatic) - out.stack = out.stack.drop(1) - else { - out.stack = out.stack.drop(2) - cleanReferencesTo(out, Field(AllRecords, field)) - in.stack match { - case v :: Record(_, bindings) :: vs => - bindings += (field -> v) - case _ => () - } - } - - case CALL_PRIMITIVE(primitive) => - // TODO: model primitives - out.stack = Unknown :: out.stack.drop(i.consumed) - - case CALL_METHOD(method, style) => style match { - case Dynamic => - out = simulateCall(in, method, static = false) - - case Static(onInstance) => - if (onInstance) { - val obj = out.stack.drop(method.info.paramTypes.length).head -// if (method.isPrimaryConstructor) { - if (method.isPrimaryConstructor) { - obj match { - case Record(_, bindings) => - for (v <- out.stack.take(method.info.paramTypes.length + 1) - if v ne obj) { - bindings ++= getBindingsForPrimaryCtor(in, method) - } - case _ => () - } - // put the Record back on the stack and remove the 'returned' value - out.stack = out.stack.drop(1 + method.info.paramTypes.length) - } else - out = simulateCall(in, method, static = false) - } else - out = simulateCall(in, method, static = true) - - case SuperCall(_) => - out = simulateCall(in, method, static = false) - } - - case BOX(tpe) => - val top = out.stack.head match { - case Deref(loc) => Boxed(loc) - case _ => Unknown - } - out.stack = top :: out.stack.tail - - case UNBOX(tpe) => - val top = out.stack.head - top match { - case Boxed(loc) => Deref(loc) :: out.stack.tail - case _ => out.stack = Unknown :: out.stack.drop(1) - } - - case NEW(kind) => - val v1 = kind match { - case REFERENCE(cls) => Record(cls, mutable.HashMap[Symbol, Value]()) - case _ => Unknown - } - out.stack = v1 :: out.stack - - case CREATE_ARRAY(elem, dims) => - out.stack = Unknown :: out.stack.drop(dims) - - case IS_INSTANCE(tpe) => - out.stack = Unknown :: out.stack.drop(1) - - case CHECK_CAST(tpe) => - out.stack = Unknown :: out.stack.drop(1) - - case SWITCH(tags, labels) => - out.stack = out.stack.drop(1) - - case JUMP(whereto) => - () - - case CJUMP(success, failure, cond, kind) => - out.stack = out.stack.drop(2) - - case CZJUMP(success, failure, cond, kind) => - out.stack = out.stack.drop(1) - - case RETURN(kind) => - if (kind != UNIT) - out.stack = out.stack.drop(1) - - case THROW(_) => - out.stack = out.stack.drop(1) - - case DROP(kind) => - out.stack = out.stack.drop(1) - - case DUP(kind) => - out.stack = out.stack.head :: out.stack - - case MONITOR_ENTER() => - out.stack = out.stack.drop(1) - - case MONITOR_EXIT() => - out.stack = out.stack.drop(1) - - case SCOPE_ENTER(_) | SCOPE_EXIT(_) => - () - - case LOAD_EXCEPTION(_) => - out.stack = Unknown :: Nil - - case _ => - dumpClassesAndAbort("Unknown instruction: " + i) - } - out - } /* def interpret */ - - /** Remove all references to this local variable from both stack - * and bindings. It is called when a new assignment destroys - * previous copy-relations. - */ - final def cleanReferencesTo(s: copyLattice.State, target: Location) { - def cleanRecord(r: Record): Record = { - retain(r.bindings) { (loc, value) => - (value match { - case Deref(loc1) if (loc1 == target) => false - case Boxed(loc1) if (loc1 == target) => false - case _ => true - }) && (target match { - case Field(AllRecords, sym1) => !(loc == sym1) - case _ => true - }) - } - r - } - - s.stack = s.stack map { v => v match { - case Record(_, bindings) => - cleanRecord(v.asInstanceOf[Record]) - case Boxed(loc1) if (loc1 == target) => Unknown - case _ => v - }} - - retain(s.bindings) { (loc, value) => - (value match { - case Deref(loc1) if (loc1 == target) => false - case Boxed(loc1) if (loc1 == target) => false - case rec @ Record(_, _) => - cleanRecord(rec) - true - case _ => true - }) && - (loc match { - case l: Location if (l == target) => false - case _ => true - }) - } - } - - /** Update the state `s` after the call to `method`. - * The stack elements are dropped and replaced by the result of the call. - * If the method is impure, all bindings to record fields are cleared. - */ - final def simulateCall(state: copyLattice.State, method: Symbol, static: Boolean): copyLattice.State = { - val out = new copyLattice.State(state.bindings, state.stack) - out.stack = out.stack.drop(method.info.paramTypes.length + (if (static) 0 else 1)) - if (method.info.resultType != definitions.UnitTpe && !method.isConstructor) - out.stack = Unknown :: out.stack - if (!isPureMethod(method)) - invalidateRecords(out) - out - } - - /** Drop everything known about mutable record fields. - * - * A simple escape analysis would help here. Some of the records we - * track never leak to other methods, therefore they can not be changed. - * We should not drop their bindings in this case. A closure object - * would be such an example. Some complications: - * - * - outer pointers. An closure escapes as an outer pointer to another - * nested closure. - */ - final def invalidateRecords(state: copyLattice.State) { - def shouldRetain(sym: Symbol): Boolean = { - if (sym.isMutable) - log("dropping binding for " + sym.fullName) - !sym.isMutable - } - state.stack = state.stack map { v => v match { - case Record(cls, bindings) => - retain(bindings) { (sym, _) => shouldRetain(sym) } - Record(cls, bindings) - case _ => v - }} - - retain(state.bindings) { (loc, value) => - value match { - case Deref(Field(rec, sym)) => shouldRetain(sym) - case Boxed(Field(rec, sym)) => shouldRetain(sym) - case _ => true - } - } - } - - /** Return bindings from an object fields to the values on the stack. This - * method has to find the correct mapping from fields to the order in which - * they are passed on the stack. It works for primary constructors. - */ - private def getBindingsForPrimaryCtor(in: copyLattice.State, ctor: Symbol): mutable.Map[Symbol, Value] = { - val paramAccessors = ctor.owner.constrParamAccessors - var values = in.stack.take(1 + ctor.info.paramTypes.length).reverse.drop(1) - val bindings = mutable.HashMap[Symbol, Value]() - - debuglog("getBindings for: " + ctor + " acc: " + paramAccessors) - - var paramTypes = ctor.tpe.paramTypes - val diff = paramTypes.length - paramAccessors.length - diff match { - case 0 => () - case 1 if ctor.tpe.paramTypes.head == ctor.owner.rawowner.tpe => - // it's an unused outer - debuglog("considering unused outer at position 0 in " + ctor.tpe.paramTypes) - paramTypes = paramTypes.tail - values = values.tail - case _ => - debuglog("giving up on " + ctor + "(diff: " + diff + ")") - return bindings - } - - // this relies on having the same order in paramAccessors and - // the arguments on the stack. It should be the same! - for ((p, i) <- paramAccessors.zipWithIndex) { -// assert(p.tpe == paramTypes(i), "In: " + ctor.fullName -// + " having acc: " + (paramAccessors map (_.tpe))+ " vs. params" + paramTypes -// + "\n\t failed at pos " + i + " with " + p.tpe + " == " + paramTypes(i)) - if (p.tpe == paramTypes(i)) - bindings += (p -> values.head) - values = values.tail - } - - debuglog("\t" + bindings) - bindings - } - - /** Is symbol `m` a pure method? - */ - final def isPureMethod(m: Symbol): Boolean = - m.isGetter // abstract getters are still pure, as we 'know' - - final override def toString() = ( - if (method eq null) List("<null>") - else method.blocks map { b => - "\nIN(%s):\t Bindings: %s".format(b.label, in(b).bindings) + - "\nIN(%s):\t Stack: %s".format(b.label, in(b).stack) - } - ).mkString - - } /* class CopyAnalysis */ -} diff --git a/src/compiler/scala/tools/nsc/backend/icode/analysis/DataFlowAnalysis.scala b/src/compiler/scala/tools/nsc/backend/icode/analysis/DataFlowAnalysis.scala deleted file mode 100644 index a378998f8f..0000000000 --- a/src/compiler/scala/tools/nsc/backend/icode/analysis/DataFlowAnalysis.scala +++ /dev/null @@ -1,92 +0,0 @@ -/* NSC -- new Scala compiler - * Copyright 2005-2013 LAMP/EPFL - * @author Martin Odersky - */ - - -package scala -package tools.nsc -package backend.icode.analysis - -import scala.collection.{ mutable, immutable } - -/** A generic framework for data flow analysis. - */ -trait DataFlowAnalysis[L <: SemiLattice] { - /** A type for program points. */ - type P <: ProgramPoint[P] - val lattice: L - - val worklist: mutable.Set[P] = new mutable.LinkedHashSet - val in: mutable.Map[P, lattice.Elem] = new mutable.HashMap - val out: mutable.Map[P, lattice.Elem] = new mutable.HashMap - val visited: mutable.HashSet[P] = new mutable.HashSet - - /** collect statistics? */ - var stat = true - - /** the number of times we iterated before reaching a fixpoint. */ - var iterations = 0 - - /* Implement this function to initialize the worklist. */ - def init(f: => Unit): Unit = { - iterations = 0 - in.clear(); out.clear(); worklist.clear(); visited.clear() - f - } - - def run(): Unit - - /** Implements forward dataflow analysis: the transfer function is - * applied when inputs to a Program point change, to obtain the new - * output value. - * - * @param f the transfer function. - */ - def forwardAnalysis(f: (P, lattice.Elem) => lattice.Elem): Unit = try { - while (!worklist.isEmpty) { - if (stat) iterations += 1 - //Console.println("worklist in: " + worklist); - val point = worklist.iterator.next(); worklist -= point; visited += point - //Console.println("taking out point: " + point + " worklist out: " + worklist); - val output = f(point, in(point)) - - if ((lattice.bottom == out(point)) || output != out(point)) { - // Console.println("Output changed at " + point - // + " from: " + out(point) + " to: " + output - // + " for input: " + in(point) + " and they are different: " + (output != out(point))) - out(point) = output - val succs = point.successors - succs foreach { p => - val updated = lattice.lub(in(p) :: (p.predecessors map out.apply), p.exceptionHandlerStart) - if(updated != in(p)) { - in(p) = updated - if (!worklist(p)) { worklist += p; } - } - } - } - } - } catch { - case e: NoSuchElementException => - Console.println("in: " + in.mkString("", "\n", "")) - Console.println("out: " + out.mkString("", "\n", "")) - e.printStackTrace - sys.error("Could not find element " + e.getMessage) - } - - def backwardAnalysis(f: (P, lattice.Elem) => lattice.Elem): Unit = - while (worklist.nonEmpty) { - if (stat) iterations += 1 - val point = worklist.head - worklist -= point - - out(point) = lattice.lub(point.successors map in.apply, exceptional = false) // TODO check for exception handlers - val input = f(point, out(point)) - - if ((lattice.bottom == in(point)) || input != in(point)) { - in(point) = input - worklist ++= point.predecessors - } - } - -} diff --git a/src/compiler/scala/tools/nsc/backend/icode/analysis/Liveness.scala b/src/compiler/scala/tools/nsc/backend/icode/analysis/Liveness.scala deleted file mode 100644 index 939641c3eb..0000000000 --- a/src/compiler/scala/tools/nsc/backend/icode/analysis/Liveness.scala +++ /dev/null @@ -1,102 +0,0 @@ -/* NSC -- new Scala compiler - * Copyright 2005-2013 LAMP/EPFL - * @author Martin Odersky - */ - - -package scala.tools.nsc -package backend.icode -package analysis - -import scala.collection.{ mutable, immutable } -import immutable.ListSet - -/** - * Compute liveness information for local variables. - * - * @author Iulian Dragos - */ -abstract class Liveness { - val global: Global - import global._ - import icodes._ - - /** The lattice for this analysis. */ - object livenessLattice extends SemiLattice { - type Elem = Set[Local] - - object top extends ListSet[Local] with ReferenceEquality - object bottom extends ListSet[Local] with ReferenceEquality - - def lub2(exceptional: Boolean)(a: Elem, b: Elem): Elem = a ++ b - } - - final class LivenessAnalysis extends DataFlowAnalysis[livenessLattice.type] { - type P = BasicBlock - val lattice = livenessLattice - var method: IMethod = _ - val gen: mutable.Map[BasicBlock, Set[Local]] = perRunCaches.newMap() - val kill: mutable.Map[BasicBlock, Set[Local]] = perRunCaches.newMap() - - def init(m: IMethod) { - this.method = m - gen.clear() - kill.clear() - - m foreachBlock { b => - val (g, k) = genAndKill(b) - gen += (b -> g) - kill += (b -> k) - } - - init { - m foreachBlock { b => - worklist += b - in(b) = lattice.bottom - out(b) = lattice.bottom - } - } - } - - import opcodes._ - - /** Return the gen and kill sets for this block. */ - def genAndKill(b: BasicBlock): (Set[Local], Set[Local]) = { - var genSet = new ListSet[Local] - var killSet = new ListSet[Local] - for (i <- b) i match { - case LOAD_LOCAL(local) if (!killSet(local)) => genSet = genSet + local - case STORE_LOCAL(local) if (!genSet(local)) => killSet = killSet + local - case _ => () - } - (genSet, killSet) - } - - override def run() { - backwardAnalysis(blockTransfer) - if (settings.debug) { - linearizer.linearize(method).foreach(b => if (b != method.startBlock) - assert(lattice.bottom != in(b), - "Block " + b + " in " + this.method + " has input equal to bottom -- not visited?")) - } - } - - def blockTransfer(b: BasicBlock, out: lattice.Elem): lattice.Elem = - gen(b) ++ (out -- kill(b)) - - /** Abstract interpretation for one instruction. Very important: - * liveness is a backward DFA, so this method should be used to compute - * liveness *before* the given instruction `i`. - */ - def interpret(out: lattice.Elem, i: Instruction): lattice.Elem = { - debuglog("- " + i + "\nout: " + out + "\n") - i match { - case LOAD_LOCAL(l) => out + l - case STORE_LOCAL(l) => out - l - case _ => out - } - } - override def toString() = - (method.blocks map (b => "\nlive-in(%s)=%s\nlive-out(%s)=%s".format(b, in(b), b, out(b)))).mkString - } /* Liveness analysis */ -} diff --git a/src/compiler/scala/tools/nsc/backend/icode/analysis/LubException.scala b/src/compiler/scala/tools/nsc/backend/icode/analysis/LubException.scala deleted file mode 100644 index e91bf7a044..0000000000 --- a/src/compiler/scala/tools/nsc/backend/icode/analysis/LubException.scala +++ /dev/null @@ -1,12 +0,0 @@ -/* NSC -- new Scala compiler - * Copyright 2005-2013 LAMP/EPFL - * @author Martin Odersky - */ - - -package scala.tools.nsc -package backend.icode.analysis - -class LubException(a: Any, b: Any, msg: String) extends Exception { - override def toString() = "Lub error: " + msg + a + b -} diff --git a/src/compiler/scala/tools/nsc/backend/icode/analysis/ProgramPoint.scala b/src/compiler/scala/tools/nsc/backend/icode/analysis/ProgramPoint.scala deleted file mode 100644 index 4e4026f526..0000000000 --- a/src/compiler/scala/tools/nsc/backend/icode/analysis/ProgramPoint.scala +++ /dev/null @@ -1,18 +0,0 @@ -/* NSC -- new Scala compiler - * Copyright 2005-2013 LAMP/EPFL - * @author Martin Odersky - */ - - -package scala.tools.nsc -package backend.icode.analysis - -/** Program points are locations in the program where we want to - * assert certain properties through data flow analysis, e.g. - * basic blocks. - */ -trait ProgramPoint[a <: ProgramPoint[a]] { - def predecessors: List[a] - def successors: List[a] - def exceptionHandlerStart: Boolean -} diff --git a/src/compiler/scala/tools/nsc/backend/icode/analysis/ReachingDefinitions.scala b/src/compiler/scala/tools/nsc/backend/icode/analysis/ReachingDefinitions.scala deleted file mode 100644 index fecd48ed27..0000000000 --- a/src/compiler/scala/tools/nsc/backend/icode/analysis/ReachingDefinitions.scala +++ /dev/null @@ -1,250 +0,0 @@ -/* NSC -- new Scala compiler - * Copyright 2005-2013 LAMP/EPFL - * @author Martin Odersky - */ - - -package scala.tools.nsc -package backend.icode -package analysis - -import scala.collection.{ mutable, immutable } -import immutable.ListSet - -/** Compute reaching definitions. We are only interested in reaching - * definitions for local variables, since values on the stack - * behave as-if in SSA form: the closest instruction which produces a value - * on the stack is a reaching definition. - */ -abstract class ReachingDefinitions { - val global: Global - import global._ - import icodes._ - - /** The lattice for reaching definitions. Elements are - * a triple (local variable, basic block, index of instruction of that basic block) - */ - object rdefLattice extends SemiLattice { - type Definition = (Local, BasicBlock, Int) - type Elem = IState[ListSet[Definition], Stack] - type StackPos = ListSet[(BasicBlock, Int)] - type Stack = List[StackPos] - - private def referenceEqualSet(name: String) = new ListSet[Definition] with ReferenceEquality { - override def toString = "<" + name + ">" - } - - val top: Elem = IState(referenceEqualSet("top"), Nil) - val bottom: Elem = IState(referenceEqualSet("bottom"), Nil) - - /** The least upper bound is set inclusion for locals, and pairwise set inclusion for stacks. */ - def lub2(exceptional: Boolean)(a: Elem, b: Elem): Elem = { - if (bottom == a) b - else if (bottom == b) a - else IState(a.vars ++ b.vars, - if (a.stack.isEmpty) b.stack - else if (b.stack.isEmpty) a.stack - else { - // !!! These stacks are with some frequency not of the same size. - // I can't reverse engineer the logic well enough to say whether this - // indicates a problem. Even if it doesn't indicate a problem, - // it'd be nice not to call zip with mismatched sequences because - // it makes it harder to spot the real problems. - val result = (a.stack, b.stack).zipped map (_ ++ _) - if (settings.debug && (a.stack.length != b.stack.length)) - devWarning(s"Mismatched stacks in ReachingDefinitions#lub2: ${a.stack}, ${b.stack}, returning $result") - result - } - ) - } - } - - class ReachingDefinitionsAnalysis extends DataFlowAnalysis[rdefLattice.type] { - type P = BasicBlock - val lattice = rdefLattice - import lattice.{ Definition, Stack, Elem, StackPos } - var method: IMethod = _ - - val gen = mutable.Map[BasicBlock, ListSet[Definition]]() - val kill = mutable.Map[BasicBlock, ListSet[Local]]() - val drops = mutable.Map[BasicBlock, Int]() - val outStack = mutable.Map[BasicBlock, Stack]() - - def init(m: IMethod) { - this.method = m - - gen.clear() - kill.clear() - drops.clear() - outStack.clear() - - m foreachBlock { b => - val (g, k) = genAndKill(b) - val (d, st) = dropsAndGen(b) - - gen += (b -> g) - kill += (b -> k) - drops += (b -> d) - outStack += (b -> st) - } - - init { - m foreachBlock { b => - worklist += b - in(b) = lattice.bottom - out(b) = lattice.bottom - } - m.exh foreach { e => - in(e.startBlock) = lattice.IState(new ListSet[Definition], List(new StackPos)) - } - } - } - - import opcodes._ - - def genAndKill(b: BasicBlock): (ListSet[Definition], ListSet[Local]) = { - var genSet = ListSet[Definition]() - var killSet = ListSet[Local]() - for ((STORE_LOCAL(local), idx) <- b.toList.zipWithIndex) { - killSet = killSet + local - genSet = updateReachingDefinition(b, idx, genSet) - } - (genSet, killSet) - } - - private def dropsAndGen(b: BasicBlock): (Int, Stack) = { - var depth, drops = 0 - var stackOut: Stack = Nil - - for ((instr, idx) <- b.toList.zipWithIndex) { - instr match { - case LOAD_EXCEPTION(_) => () - case _ if instr.consumed > depth => - drops += (instr.consumed - depth) - depth = 0 - stackOut = Nil - case _ => - stackOut = stackOut.drop(instr.consumed) - depth -= instr.consumed - } - var prod = instr.produced - depth += prod - while (prod > 0) { - stackOut ::= ListSet((b, idx)) - prod -= 1 - } - } -// Console.println("drops(" + b + ") = " + drops) -// Console.println("stackout(" + b + ") = " + stackOut) - (drops, stackOut) - } - - override def run() { - forwardAnalysis(blockTransfer) - if (settings.debug) { - linearizer.linearize(method).foreach(b => if (b != method.startBlock) - assert(lattice.bottom != in(b), - "Block " + b + " in " + this.method + " has input equal to bottom -- not visited? " + in(b) - + ": bot: " + lattice.bottom - + "\nin(b) == bottom: " + (in(b) == lattice.bottom) - + "\nbottom == in(b): " + (lattice.bottom == in(b)))) - } - } - - import opcodes._ - import lattice.IState - def updateReachingDefinition(b: BasicBlock, idx: Int, rd: ListSet[Definition]): ListSet[Definition] = { - val STORE_LOCAL(local) = b(idx) - val tmp = local - (rd filter { case (l, _, _) => l != tmp }) + ((tmp, b, idx)) - } - - private def blockTransfer(b: BasicBlock, in: lattice.Elem): lattice.Elem = { - var locals: ListSet[Definition] = (in.vars filter { case (l, _, _) => !kill(b)(l) }) ++ gen(b) - if (locals eq lattice.bottom.vars) locals = new ListSet[Definition] - IState(locals, outStack(b) ::: in.stack.drop(drops(b))) - } - - /** Return the reaching definitions corresponding to the point after idx. */ - def interpret(b: BasicBlock, idx: Int, in: lattice.Elem): Elem = { - var locals = in.vars - var stack = in.stack - val instr = b(idx) - - instr match { - case STORE_LOCAL(l1) => - locals = updateReachingDefinition(b, idx, locals) - stack = stack.drop(instr.consumed) - case LOAD_EXCEPTION(_) => - stack = Nil - case _ => - stack = stack.drop(instr.consumed) - } - - var prod = instr.produced - while (prod > 0) { - stack ::= ListSet((b, idx)) - prod -= 1 - } - - IState(locals, stack) - } - - /** Return the instructions that produced the 'm' elements on the stack, below given 'depth'. - * for instance, findefs(bb, idx, 1, 1) returns the instructions that might have produced the - * value found below the topmost element of the stack. - */ - def findDefs(bb: BasicBlock, idx: Int, m: Int, depth: Int): List[(BasicBlock, Int)] = if (idx > 0) { - assert(bb.closed, bb) - - val instrs = bb.getArray - var res: List[(BasicBlock, Int)] = Nil - var i = idx - var n = m - var d = depth - // "I look for who produced the 'n' elements below the 'd' topmost slots of the stack" - while (n > 0 && i > 0) { - i -= 1 - val prod = instrs(i).produced - if (prod > d) { - res = (bb, i) :: res - n = n - (prod - d) - instrs(i) match { - case LOAD_EXCEPTION(_) => () - case _ => d = instrs(i).consumed - } - } else { - d -= prod - d += instrs(i).consumed - } - } - - if (n > 0) { - val stack = this.in(bb).stack - assert(stack.length >= n, "entry stack is too small, expected: " + n + " found: " + stack) - stack.drop(d).take(n) foreach { defs => - res = defs.toList ::: res - } - } - res - } else { - val stack = this.in(bb).stack - assert(stack.length >= m, "entry stack is too small, expected: " + m + " found: " + stack) - stack.drop(depth).take(m) flatMap (_.toList) - } - - /** Return the definitions that produced the topmost 'm' elements on the stack, - * and that reach the instruction at index 'idx' in basic block 'bb'. - */ - def findDefs(bb: BasicBlock, idx: Int, m: Int): List[(BasicBlock, Int)] = - findDefs(bb, idx, m, 0) - - override def toString: String = { - if (method eq null) "<null>" - else method.code.blocks map { b => - " entry(%s) = %s\n".format(b, in(b)) + - " exit(%s) = %s\n".format(b, out(b)) - } mkString ("ReachingDefinitions {\n", "\n", "\n}") - } - } -} diff --git a/src/compiler/scala/tools/nsc/backend/icode/analysis/SemiLattice.scala b/src/compiler/scala/tools/nsc/backend/icode/analysis/SemiLattice.scala deleted file mode 100644 index f718c705c2..0000000000 --- a/src/compiler/scala/tools/nsc/backend/icode/analysis/SemiLattice.scala +++ /dev/null @@ -1,49 +0,0 @@ -/* NSC -- new Scala compiler - * Copyright 2005-2013 LAMP/EPFL - * @author Martin Odersky - */ - -package scala.tools.nsc -package backend.icode -package analysis - -/** A complete lattice. - */ -trait SemiLattice { - type Elem <: AnyRef - - /** Hold together local variable and stack state. The - * equals method uses reference equality for top and bottom, - * and structural equality for other values. - */ - final case class IState[V, S](vars: V, stack: S) { - override def hashCode = vars.hashCode + stack.hashCode - override def equals(other: Any): Boolean = other match { - case x: IState[_, _] => - if ((this eq bottom) || (this eq top) || (x eq bottom) || (x eq top)) this eq x - else stack == x.stack && vars == x.vars - case _ => - false - } - private def tstring(x: Any): String = x match { - case xs: TraversableOnce[_] => xs map tstring mkString " " - case _ => "" + x - } - override def toString = "IState(" + tstring(vars) + ", " + tstring(stack) + ")" - } - - /** Return the least upper bound of a and b. */ - def lub2(exceptional: Boolean)(a: Elem, b: Elem): Elem - - /** Return the top element. */ - def top: Elem - - /** Return the bottom element. */ - def bottom: Elem - - /** Compute the least upper bound of a list of elements. */ - def lub(xs: List[Elem], exceptional: Boolean): Elem = - if (xs.isEmpty) bottom - else try xs reduceLeft lub2(exceptional) - catch { case e: LubException => Console.println("Lub on blocks: " + xs) ; throw e } -} diff --git a/src/compiler/scala/tools/nsc/backend/icode/analysis/TypeFlowAnalysis.scala b/src/compiler/scala/tools/nsc/backend/icode/analysis/TypeFlowAnalysis.scala deleted file mode 100644 index 64c9901a3e..0000000000 --- a/src/compiler/scala/tools/nsc/backend/icode/analysis/TypeFlowAnalysis.scala +++ /dev/null @@ -1,725 +0,0 @@ -/* NSC -- new Scala compiler - * Copyright 2005-2013 LAMP/EPFL - * @author Martin Odersky - */ - -package scala -package tools.nsc -package backend.icode.analysis - -import scala.collection.{mutable, immutable} -import java.util.concurrent.TimeUnit - -/** A data-flow analysis on types, that works on `ICode`. - * - * @author Iulian Dragos - */ -abstract class TypeFlowAnalysis { - val global: Global - import global._ - import definitions.{ ObjectClass, NothingClass, AnyRefClass, StringClass, ThrowableClass } - - /** The lattice of ICode types. - */ - object typeLattice extends SemiLattice { - type Elem = icodes.TypeKind - - val top = icodes.REFERENCE(ObjectClass) - val bottom = icodes.REFERENCE(NothingClass) - - def lub2(exceptional: Boolean)(a: Elem, b: Elem) = - if (a eq bottom) b - else if (b eq bottom) a - else icodes.lub(a, b) - } - - /** The lattice of type stacks. It is a straight forward extension of - * the type lattice (lub is pairwise lub of the list elements). - */ - object typeStackLattice extends SemiLattice { - import icodes._ - type Elem = TypeStack - - val top = new TypeStack - val bottom = new TypeStack - val exceptionHandlerStack = new TypeStack(List(REFERENCE(AnyRefClass))) - - def lub2(exceptional: Boolean)(s1: TypeStack, s2: TypeStack) = { - if (s1 eq bottom) s2 - else if (s2 eq bottom) s1 - else if ((s1 eq exceptionHandlerStack) || (s2 eq exceptionHandlerStack)) sys.error("merging with exhan stack") - else { -// if (s1.length != s2.length) -// throw new CheckerException("Incompatible stacks: " + s1 + " and " + s2); - new TypeStack((s1.types, s2.types).zipped map icodes.lub) - } - } - } - - /** A map which returns the bottom type for unfound elements */ - class VarBinding extends mutable.HashMap[icodes.Local, icodes.TypeKind] { - override def default(l: icodes.Local) = typeLattice.bottom - - def this(o: VarBinding) = { - this() - this ++= o - } - } - - /** The type flow lattice contains a binding from local variable - * names to types and a type stack. - */ - object typeFlowLattice extends SemiLattice { - type Elem = IState[VarBinding, icodes.TypeStack] - - val top = new Elem(new VarBinding, typeStackLattice.top) - val bottom = new Elem(new VarBinding, typeStackLattice.bottom) - - def lub2(exceptional: Boolean)(a: Elem, b: Elem) = { - val IState(env1, _) = a - val IState(env2, _) = b - - val resultingLocals = new VarBinding - env1 foreach { case (k, v) => - resultingLocals += ((k, typeLattice.lub2(exceptional)(v, env2(k)))) - } - env2 collect { case (k, v) if resultingLocals(k) eq typeLattice.bottom => - resultingLocals += ((k, typeLattice.lub2(exceptional)(v, env1(k)))) - } - val stack = - if (exceptional) typeStackLattice.exceptionHandlerStack - else typeStackLattice.lub2(exceptional)(a.stack, b.stack) - - IState(resultingLocals, stack) - } - } - - val timer = new Timer - - class MethodTFA extends DataFlowAnalysis[typeFlowLattice.type] { - import icodes._ - import icodes.opcodes._ - - type P = BasicBlock - val lattice = typeFlowLattice - - val STRING = icodes.REFERENCE(StringClass) - var method: IMethod = _ - - /** Initialize the in/out maps for the analysis of the given method. */ - def init(m: icodes.IMethod) { - this.method = m - //typeFlowLattice.lubs = 0 - init { - worklist += m.startBlock - worklist ++= (m.exh map (_.startBlock)) - m foreachBlock { b => - in(b) = typeFlowLattice.bottom - out(b) = typeFlowLattice.bottom - } - - // start block has var bindings for each of its parameters - val entryBindings = new VarBinding ++= (m.params map (p => ((p, p.kind)))) - in(m.startBlock) = lattice.IState(entryBindings, typeStackLattice.bottom) - - m.exh foreach { e => - in(e.startBlock) = lattice.IState(in(e.startBlock).vars, typeStackLattice.exceptionHandlerStack) - } - } - } - - def this(m: icodes.IMethod) { - this() - init(m) - } - - def run() = { - timer.start() - // icodes.lubs0 = 0 - forwardAnalysis(blockTransfer) - timer.stop - if (settings.debug) { - linearizer.linearize(method).foreach(b => if (b != method.startBlock) - assert(visited.contains(b), - "Block " + b + " in " + this.method + " has input equal to bottom -- not visited? .." + visited)) - } - // log("" + method.symbol.fullName + " [" + method.code.blocks.size + " blocks] " - // + "\n\t" + iterations + " iterations: " + t + " ms." - // + "\n\tlubs: " + typeFlowLattice.lubs + " out of which " + icodes.lubs0 + " typer lubs") - } - - def blockTransfer(b: BasicBlock, in: lattice.Elem): lattice.Elem = { - var result = lattice.IState(new VarBinding(in.vars), new TypeStack(in.stack)) - var instrs = b.toList - while(!instrs.isEmpty) { - val i = instrs.head - result = mutatingInterpret(result, i) - instrs = instrs.tail - } - result - } - - /** Abstract interpretation for one instruction. */ - def interpret(in: typeFlowLattice.Elem, i: Instruction): typeFlowLattice.Elem = { - val out = lattice.IState(new VarBinding(in.vars), new TypeStack(in.stack)) - mutatingInterpret(out, i) - } - - def mutatingInterpret(out: typeFlowLattice.Elem, i: Instruction): typeFlowLattice.Elem = { - val bindings = out.vars - val stack = out.stack - - if (settings.debug) { - // Console.println("[before] Stack: " + stack); - // Console.println(i); - } - i match { - - case THIS(clasz) => stack push toTypeKind(clasz.tpe) - case CONSTANT(const) => stack push toTypeKind(const.tpe) - - case LOAD_ARRAY_ITEM(kind) => - stack.pop2 match { - case (idxKind, ARRAY(elem)) => - assert(idxKind == INT || idxKind == CHAR || idxKind == SHORT || idxKind == BYTE) - stack.push(elem) - case (_, _) => - stack.push(kind) - } - - case LOAD_LOCAL(local) => - val t = bindings(local) - stack push (if (t == typeLattice.bottom) local.kind else t) - - case LOAD_FIELD(field, isStatic) => - if (!isStatic) { stack.pop } - stack push toTypeKind(field.tpe) - - case LOAD_MODULE(module) => stack push toTypeKind(module.tpe) - case STORE_ARRAY_ITEM(kind) => stack.pop3 - case STORE_LOCAL(local) => val t = stack.pop; bindings += (local -> t) - case STORE_THIS(_) => stack.pop - - case STORE_FIELD(field, isStatic) => if (isStatic) stack.pop else stack.pop2 - - case CALL_PRIMITIVE(primitive) => - primitive match { - case Negation(kind) => stack.pop; stack.push(kind) - - case Test(_, kind, zero) => - stack.pop - if (!zero) { stack.pop } - stack push BOOL - - case Comparison(_, _) => stack.pop2; stack push INT - - case Arithmetic(op, kind) => - stack.pop - if (op != NOT) { stack.pop } - val k = kind match { - case BYTE | SHORT | CHAR => INT - case _ => kind - } - stack push k - - case Logical(op, kind) => stack.pop2; stack push kind - case Shift(op, kind) => stack.pop2; stack push kind - case Conversion(src, dst) => stack.pop; stack push dst - case ArrayLength(kind) => stack.pop; stack push INT - case StartConcat => stack.push(ConcatClass) - case EndConcat => stack.pop; stack.push(STRING) - case StringConcat(el) => stack.pop2; stack push ConcatClass - } - - case cm @ CALL_METHOD(_, _) => - stack pop cm.consumed - cm.producedTypes foreach (stack push _) - - case BOX(kind) => stack.pop; stack.push(BOXED(kind)) - case UNBOX(kind) => stack.pop; stack.push(kind) - - case NEW(kind) => stack.push(kind) - - case CREATE_ARRAY(elem, dims) => stack.pop(dims); stack.push(ARRAY(elem)) - - case IS_INSTANCE(tpe) => stack.pop; stack.push(BOOL) - case CHECK_CAST(tpe) => stack.pop; stack.push(tpe) - - case _: SWITCH => stack.pop - case _: JUMP => () - case _: CJUMP => stack.pop2 - case _: CZJUMP => stack.pop - - case RETURN(kind) => if (kind != UNIT) { stack.pop } - case THROW(_) => stack.pop - - case DROP(kind) => stack.pop - case DUP(kind) => stack.push(stack.head) - - case MONITOR_ENTER() | MONITOR_EXIT() => stack.pop - - case SCOPE_ENTER(_) | SCOPE_EXIT(_) => () - - case LOAD_EXCEPTION(clasz) => - stack.pop(stack.length) - stack.push(toTypeKind(clasz.tpe)) - - case _ => - dumpClassesAndAbort("Unknown instruction: " + i) - } - out - } // interpret - - abstract class InferredType { - /** Return the type kind pointed by this inferred type. */ - def getKind(in: lattice.Elem): icodes.TypeKind = this match { - case Const(k) => - k - case TypeOfVar(l: icodes.Local) => - if (in.vars.isDefinedAt(l)) in.vars(l) else l.kind - case TypeOfStackPos(n: Int) => - assert(in.stack.length >= n) - in.stack(n) - } - } - /** A type that does not depend on input to the transfer function. */ - case class Const(t: icodes.TypeKind) extends InferredType - /** The type of a given local variable. */ - case class TypeOfVar(l: icodes.Local) extends InferredType - /** The type found at a stack position. */ - case class TypeOfStackPos(n: Int) extends InferredType - - abstract class Gen - case class Bind(l: icodes.Local, t: InferredType) extends Gen - case class Push(t: InferredType) extends Gen - - /** A flow transfer function of a basic block. */ - class TransferFunction(consumed: Int, gens: List[Gen]) extends (lattice.Elem => lattice.Elem) { - def apply(in: lattice.Elem): lattice.Elem = { - val out = lattice.IState(new VarBinding(in.vars), new TypeStack(in.stack)) - val stack = out.stack - - out.stack.pop(consumed) - for (g <- gens) g match { - case Bind(l, t) => - out.vars += (l -> t.getKind(in)) - case Push(t) => - stack.push(t.getKind(in)) - } - out - } - } - } - - case class CallsiteInfo(bb: icodes.BasicBlock, receiver: Symbol, stackLength: Int, concreteMethod: Symbol) - - /** - - A full type-flow analysis on a method computes in- and out-flows for each basic block (that's what MethodTFA does). - - For the purposes of Inliner, doing so guarantees that an abstract typestack-slot is available by the time an inlining candidate (a CALL_METHOD instruction) is visited. - This subclass (MTFAGrowable) of MethodTFA also aims at performing such analysis on CALL_METHOD instructions, with some differences: - - (a) early screening is performed while the type-flow is being computed (in an override of `blockTransfer`) by testing a subset of the conditions that Inliner checks later. - The reasoning here is: if the early check fails at some iteration, there's no chance a follow-up iteration (with a yet more lub-ed typestack-slot) will succeed. - Failure is sufficient to remove that particular CALL_METHOD from the typeflow's `remainingCALLs`. - A forward note: in case inlining occurs at some basic block B, all blocks reachable from B get their CALL_METHOD instructions considered again as candidates - (because of the more precise types that -- perhaps -- can be computed). - - (b) in case the early check does not fail, no conclusive decision can be made, thus the CALL_METHOD stays `isOnwatchlist`. - - In other words, `remainingCALLs` tracks those callsites that still remain as candidates for inlining, so that Inliner can focus on those. - `remainingCALLs` also caches info about the typestack just before the callsite, so as to spare computing them again at inlining time. - - Besides caching, a further optimization involves skipping those basic blocks whose in-flow and out-flow isn't needed anyway (as explained next). - A basic block lacking a callsite in `remainingCALLs`, when visited by the standard algorithm, won't cause any inlining. - But as we know from the way type-flows are computed, computing the in- and out-flow for a basic block relies in general on those of other basic blocks. - In detail, we want to focus on that sub-graph of the CFG such that control flow may reach a remaining candidate callsite. - Those basic blocks not in that subgraph can be skipped altogether. That's why: - - `forwardAnalysis()` in `MTFAGrowable` now checks for inclusion of a basic block in `relevantBBs` - - same check is performed before adding a block to the worklist, and as part of choosing successors. - The bookkeeping supporting on-the-fly pruning of irrelevant blocks requires overriding most methods of the dataflow-analysis. - - The rest of the story takes place in Inliner, which does not visit all of the method's basic blocks but only on those represented in `remainingCALLs`. - - @author Miguel Garcia, http://lampwww.epfl.ch/~magarcia/ScalaCompilerCornerReloaded/ - - */ - class MTFAGrowable extends MethodTFA { - - import icodes._ - - val remainingCALLs = mutable.Map.empty[opcodes.CALL_METHOD, CallsiteInfo] - - val preCandidates = mutable.Set.empty[BasicBlock] - - var callerLin: Traversable[BasicBlock] = null - - override def run { - - timer.start() - forwardAnalysis(blockTransfer) - timer.stop - - /* Now that `forwardAnalysis(blockTransfer)` has finished, all inlining candidates can be found in `remainingCALLs`, - whose keys are callsites and whose values are pieces of information about the typestack just before the callsite in question. - In order to keep `analyzeMethod()` simple, we collect in `preCandidates` those basic blocks containing at least one candidate. */ - preCandidates.clear() - for(rc <- remainingCALLs) { - preCandidates += rc._2.bb - } - - if (settings.debug) { - for(b <- callerLin; if (b != method.startBlock) && preCandidates(b)) { - assert(visited.contains(b), - "Block " + b + " in " + this.method + " has input equal to bottom -- not visited? .." + visited) - } - } - - } - - var shrinkedWatchlist = false - - /* - This is the method where information cached elsewhere is put to use. References are given those other places that populate those caches. - - The goal is avoiding computing type-flows for blocks we don't need (ie blocks not tracked in `relevantBBs`). The method used to add to `relevantBBs` is `putOnRadar`. - - Moreover, it's often the case that the last CALL_METHOD of interest ("of interest" equates to "being tracked in `isOnWatchlist`) isn't the last instruction on the block. - There are cases where the typeflows computed past this `lastInstruction` are needed, and cases when they aren't. - The reasoning behind this decision is described in `populatePerimeter()`. All `blockTransfer()` needs to do (in order to know at which instruction it can stop) - is querying `isOnPerimeter`. - - Upon visiting a CALL_METHOD that's an inlining candidate, the relevant pieces of information about the pre-instruction typestack are collected for future use. - That is, unless the candidacy test fails. The reasoning here is: if such early check fails at some iteration, there's no chance a follow-up iteration - (with a yet more lub-ed typestack-slot) will succeed. In case of failure we can safely remove the CALL_METHOD from both `isOnWatchlist` and `remainingCALLs`. - - */ - override def blockTransfer(b: BasicBlock, in: lattice.Elem): lattice.Elem = { - var result = lattice.IState(new VarBinding(in.vars), new TypeStack(in.stack)) - - val stopAt = if(isOnPerimeter(b)) lastInstruction(b) else null - var isPastLast = false - - var instrs = b.toList - while(!isPastLast && !instrs.isEmpty) { - val i = instrs.head - - if(isOnWatchlist(i)) { - val cm = i.asInstanceOf[opcodes.CALL_METHOD] - val msym = cm.method - val paramsLength = msym.info.paramTypes.size - val receiver = result.stack.types.drop(paramsLength).head match { - case REFERENCE(s) => s - case _ => NoSymbol // e.g. the scrutinee is BOX(s) or ARRAY - } - val concreteMethod = inliner.lookupImplFor(msym, receiver) - val isCandidate = { - ( inliner.isClosureClass(receiver) || concreteMethod.isEffectivelyFinalOrNotOverridden || receiver.isEffectivelyFinalOrNotOverridden ) && - !blackballed(concreteMethod) - } - if(isCandidate) { - remainingCALLs(cm) = CallsiteInfo(b, receiver, result.stack.length, concreteMethod) - } else { - remainingCALLs.remove(cm) - isOnWatchlist.remove(cm) - shrinkedWatchlist = true - } - } - - isPastLast = (i eq stopAt) - - if(!isPastLast) { - result = mutatingInterpret(result, i) - instrs = instrs.tail - } - } - - result - } // end of method blockTransfer - - val isOnWatchlist = mutable.Set.empty[Instruction] - - val warnIfInlineFails = mutable.Set.empty[opcodes.CALL_METHOD] // cache for a given IMethod (ie cleared on Inliner.analyzeMethod). - - /* Each time CallerCalleeInfo.isSafeToInline determines a concrete callee is unsafe to inline in the current caller, - the fact is recorded in this TFA instance for the purpose of avoiding devoting processing to that callsite next time. - The condition of "being unsafe to inline in the current caller" sticks across inlinings and TFA re-inits - because it depends on the instructions of the callee, which stay unchanged during the course of `analyzeInc(caller)` - (with the caveat of the side-effecting `makePublic` in `helperIsSafeToInline`).*/ - val knownUnsafe = mutable.Set.empty[Symbol] - val knownSafe = mutable.Set.empty[Symbol] - val knownNever = mutable.Set.empty[Symbol] // `knownNever` needs be cleared only at the very end of the inlining phase (unlike `knownUnsafe` and `knownSafe`) - final def blackballed(msym: Symbol): Boolean = { knownUnsafe(msym) || knownNever(msym) } - - val relevantBBs = mutable.Set.empty[BasicBlock] - - /* - * Rationale to prevent some methods from ever being inlined: - * - * (1) inlining getters and setters results in exposing a private field, - * which may itself prevent inlining of the caller (at best) or - * lead to situations like SI-5442 ("IllegalAccessError when mixing optimized and unoptimized bytecode") - * - * (2) only invocations having a receiver object are considered (ie no static-methods are ever inlined). - * This is taken care of by checking `isDynamic` (ie virtual method dispatch) and `Static(true)` (ie calls to private members) - */ - private def isPreCandidate(cm: opcodes.CALL_METHOD): Boolean = { - val msym = cm.method - val style = cm.style - - !blackballed(msym) && - !msym.isConstructor && - (!msym.isAccessor || inliner.isClosureClass(msym.owner)) && - (style.isDynamic || (style.hasInstance && style.isStatic)) - } - - override def init(m: icodes.IMethod) { - super.init(m) - remainingCALLs.clear() - knownUnsafe.clear() - knownSafe.clear() - // initially populate the watchlist with all callsites standing a chance of being inlined - isOnWatchlist.clear() - relevantBBs.clear() - warnIfInlineFails.clear() - /* TODO Do we want to perform inlining in non-finally exception handlers? - * Seems counterproductive (the larger the method the less likely it will be JITed. - * It's not that putting on radar only `linearizer linearizeAt (m, m.startBlock)` makes for much shorter inlining times (a minor speedup nonetheless) - * but the effect on method size could be explored. */ - putOnRadar(m.linearizedBlocks(linearizer)) - populatePerimeter() - // usually but not always true (counterexample in SI-6015) `(relevantBBs.isEmpty || relevantBBs.contains(m.startBlock))` - } - - def conclusives(b: BasicBlock): List[opcodes.CALL_METHOD] = { - knownBeforehand(b) filter { cm => inliner.isMonadicMethod(cm.method) || inliner.hasInline(cm.method) } - } - - def knownBeforehand(b: BasicBlock): List[opcodes.CALL_METHOD] = { - b.toList collect { case c : opcodes.CALL_METHOD => c } filter { cm => isPreCandidate(cm) && isReceiverKnown(cm) } - } - - private def isReceiverKnown(cm: opcodes.CALL_METHOD): Boolean = { - cm.method.isEffectivelyFinalOrNotOverridden && cm.method.owner.isEffectivelyFinalOrNotOverridden - } - - private def putOnRadar(blocks: Traversable[BasicBlock]) { - for(bb <- blocks) { - val calls = bb.toList collect { case cm : opcodes.CALL_METHOD => cm } - for(c <- calls; if(inliner.hasInline(c.method))) { - warnIfInlineFails += c - } - val preCands = calls filter isPreCandidate - isOnWatchlist ++= preCands - } - relevantBBs ++= blocks - } - - /* those BBs in the argument are also included in the result */ - private def transitivePreds(starters: Traversable[BasicBlock]): Set[BasicBlock] = { - val result = mutable.Set.empty[BasicBlock] - var toVisit: List[BasicBlock] = starters.toList.distinct - while(toVisit.nonEmpty) { - val h = toVisit.head - toVisit = toVisit.tail - result += h - for(p <- h.predecessors; if !result(p) && !toVisit.contains(p)) { toVisit = p :: toVisit } - } - result.toSet - } - - /* A basic block B is "on the perimeter" of the current control-flow subgraph if none of its successors belongs to that subgraph. - * In that case, for the purposes of inlining, we're interested in the typestack right before the last inline candidate in B, not in those afterwards. - * In particular we can do without computing the outflow at B. */ - private def populatePerimeter() { - isOnPerimeter.clear() - var done = true - do { - val (frontier, toPrune) = (relevantBBs filter hasNoRelevantSuccs) partition isWatching - isOnPerimeter ++= frontier - relevantBBs --= toPrune - done = toPrune.isEmpty - } while(!done) - - lastInstruction.clear() - for (b <- isOnPerimeter; lastIns = b.toList.reverse find isOnWatchlist) { - lastInstruction += (b -> lastIns.get.asInstanceOf[opcodes.CALL_METHOD]) - } - - // assertion: "no relevant block can have a predecessor that is on perimeter" - assert((for (b <- relevantBBs; if transitivePreds(b.predecessors) exists isOnPerimeter) yield b).isEmpty) - } - - private val isOnPerimeter = mutable.Set.empty[BasicBlock] - private val lastInstruction = mutable.Map.empty[BasicBlock, opcodes.CALL_METHOD] - - def hasNoRelevantSuccs(x: BasicBlock): Boolean = { !(x.successors exists relevantBBs) } - - def isWatching(x: BasicBlock): Boolean = (x.toList exists isOnWatchlist) - - - - - /** - - This method is invoked after one or more inlinings have been performed in basic blocks whose in-flow is non-bottom (this makes a difference later). - What we know about those inlinings is given by: - - - `staleOut`: These are the blocks where a callsite was inlined. - For each callsite, all instructions in that block before the callsite were left in the block, and the rest moved to an `afterBlock`. - The out-flow of these basic blocks is thus in general stale, that's why we'll add them to the TFA worklist. - - - `inlined` : These blocks were spliced into the method's CFG as part of inlining. Being new blocks, they haven't been visited yet by the typeflow analysis. - - - `staleIn` : These blocks are what `doInline()` calls `afterBlock`s, ie the new home for instructions that previously appeared - after a callsite in a `staleOut` block. - - Based on the above information, we have to bring up-to-date the caches that `forwardAnalysis` and `blockTransfer` use to skip blocks and instructions. - Those caches are `relevantBBs` and `isOnPerimeter` (for blocks) and `isOnWatchlist` and `lastInstruction` (for CALL_METHODs). - Please notice that all `inlined` and `staleIn` blocks are reachable from `staleOut` blocks. - - The update takes place in two steps: - - (1) `staleOut foreach { so => putOnRadar(linearizer linearizeAt (m, so)) }` - This results in initial populations for `relevantBBs` and `isOnWatchlist`. - Because of the way `isPreCandidate` reuses previous decision-outcomes that are still valid, - this already prunes some candidates standing no chance of being inlined. - - (2) `populatePerimeter()` - Based on the CFG-subgraph determined in (1) as reflected in `relevantBBs`, - this method detects some blocks whose typeflows aren't needed past a certain CALL_METHOD - (not needed because none of its successors is relevant for the purposes of inlining, see `hasNoRelevantSuccs`). - The blocks thus chosen are said to be "on the perimeter" of the CFG-subgraph. - For each of them, its `lastInstruction` (after which no more typeflows are needed) is found. - - */ - def reinit(m: icodes.IMethod, staleOut: List[BasicBlock], inlined: scala.collection.Set[BasicBlock], staleIn: scala.collection.Set[BasicBlock]) { - if (this.method == null || this.method.symbol != m.symbol) { - init(m) - return - } else if(staleOut.isEmpty && inlined.isEmpty && staleIn.isEmpty) { - // this promotes invoking reinit if in doubt, no performance degradation will ensue! - return - } - - worklist.clear() // calling reinit(f: => Unit) would also clear visited, thus forgetting about blocks visited before reinit. - - // asserts conveying an idea what CFG shapes arrive here: - // staleIn foreach (p => assert( !in.isDefinedAt(p), p)) - // staleIn foreach (p => assert(!out.isDefinedAt(p), p)) - // inlined foreach (p => assert( !in.isDefinedAt(p), p)) - // inlined foreach (p => assert(!out.isDefinedAt(p), p)) - // inlined foreach (p => assert(!p.successors.isEmpty || p.lastInstruction.isInstanceOf[icodes.opcodes.THROW], p)) - // staleOut foreach (p => assert( in.isDefinedAt(p), p)) - - // remainingCALLs.clear() - isOnWatchlist.clear() - relevantBBs.clear() - - // never rewrite in(m.startBlock) - staleOut foreach { b => - enqueue(b) - out(b) = typeFlowLattice.bottom - } - // nothing else is added to the worklist, bb's reachable via succs will be tfa'ed - blankOut(inlined) - blankOut(staleIn) - // no need to add startBlocks from m.exh - - staleOut foreach { so => putOnRadar(linearizer linearizeAt (m, so)) } - populatePerimeter() - - } // end of method reinit - - /* this is not a general purpose method to add to the worklist, - * because the assert is expected to hold only when called from MTFAGrowable.reinit() */ - private def enqueue(b: BasicBlock) { - assert(in(b) ne typeFlowLattice.bottom) - if(!worklist.contains(b)) { worklist += b } - } - - private def blankOut(blocks: scala.collection.Set[BasicBlock]) { - blocks foreach { b => - in(b) = typeFlowLattice.bottom - out(b) = typeFlowLattice.bottom - } - } - - /* - This is basically the plain-old forward-analysis part of a dataflow algorithm, - adapted to skip non-relevant blocks (as determined by `reinit()` via `populatePerimeter()`). - - The adaptations are: - - - only relevant blocks dequeued from the worklist move on to have the transfer function applied - - - `visited` now means the transfer function was applied to the block, - but please notice that this does not imply anymore its out-flow to be different from bottom, - because a block on the perimeter will have per-instruction typeflows computed only up to its `lastInstruction`. - In case you need to know whether a visted block `v` has been "fully visited", evaluate `out(v) ne typeflowLattice.bottom` - - - given that the transfer function may remove callsite-candidates from the watchlist (thus, they are not candidates anymore) - there's an opportunity to detect whether a previously relevant block has been left without candidates. - That's what `shrinkedWatchlist` detects. Provided the block was on the perimeter, we know we can skip it from now now, - and we can also constrain the CFG-subgraph by finding a new perimeter (thus the invocation to `populatePerimeter()`). - */ - override def forwardAnalysis(f: (P, lattice.Elem) => lattice.Elem): Unit = { - while (!worklist.isEmpty && relevantBBs.nonEmpty) { - if (stat) iterations += 1 - val point = worklist.iterator.next(); worklist -= point - if(relevantBBs(point)) { - shrinkedWatchlist = false - val output = f(point, in(point)) - visited += point - if(isOnPerimeter(point)) { - if(shrinkedWatchlist && !isWatching(point)) { - relevantBBs -= point - populatePerimeter() - } - } else { - val propagate = ((lattice.bottom == out(point)) || output != out(point)) - if (propagate) { - out(point) = output - val succs = point.successors filter relevantBBs - succs foreach { p => - assert((p.predecessors filter isOnPerimeter).isEmpty) - val existing = in(p) - // TODO move the following assertion to typeFlowLattice.lub2 for wider applicability (ie MethodTFA in addition to MTFAGrowable). - assert(existing == lattice.bottom || - p.exceptionHandlerStart || - (output.stack.length == existing.stack.length), - "Trying to merge non-bottom type-stacks with different stack heights. For a possible cause see SI-6157.") - val updated = lattice.lub(List(output, existing), p.exceptionHandlerStart) - if(updated != in(p)) { - in(p) = updated - enqueue(p) - } - } - } - } - } - } - } - - } - - class Timer { - var millis = 0L - - private var lastStart = 0L - - def start() { - lastStart = System.nanoTime() - } - - /** Stop the timer and return the number of milliseconds since the last - * call to start. The 'millis' field is increased by the elapsed time. - */ - def stop: Long = { - val elapsed = TimeUnit.NANOSECONDS.toMillis(System.nanoTime() - lastStart) - millis += elapsed - elapsed - } - } -} diff --git a/src/compiler/scala/tools/nsc/backend/jvm/AsmUtils.scala b/src/compiler/scala/tools/nsc/backend/jvm/AsmUtils.scala index cd7e0b83e8..402dc66a7f 100644 --- a/src/compiler/scala/tools/nsc/backend/jvm/AsmUtils.scala +++ b/src/compiler/scala/tools/nsc/backend/jvm/AsmUtils.scala @@ -5,11 +5,15 @@ package scala.tools.nsc.backend.jvm -import scala.tools.asm.tree.{InsnList, AbstractInsnNode, ClassNode, MethodNode} -import java.io.{StringWriter, PrintWriter} -import scala.tools.asm.util.{CheckClassAdapter, TraceClassVisitor, TraceMethodVisitor, Textifier} -import scala.tools.asm.{ClassWriter, Attribute, ClassReader} -import scala.collection.convert.decorateAsScala._ +import scala.tools.asm.tree.{AbstractInsnNode, ClassNode, FieldNode, InsnList, MethodNode} +import java.io.{PrintWriter, StringWriter} +import java.util + +import scala.tools.asm.util.{CheckClassAdapter, Textifier, TraceClassVisitor, TraceMethodVisitor} +import scala.tools.asm.{Attribute, ClassReader, ClassWriter} +import scala.collection.JavaConverters._ +import scala.concurrent.duration.Duration +import scala.concurrent.{Await, Future} import scala.tools.nsc.backend.jvm.analysis.InitialProducer import scala.tools.nsc.backend.jvm.opt.InlineInfoAttributePrototype @@ -29,7 +33,7 @@ object AsmUtils { final val traceClassPattern = "" /** - * Print the bytedcode of classes as they are serialized by the ASM library. The serialization + * Print the bytecode of classes as they are serialized by the ASM library. The serialization * performed by `asm.ClassWriter` can change the code generated by GenBCode. For example, it * introduces stack map frames, it computes the maximal stack sizes, and it replaces dead * code by NOPs (see also https://github.com/scala/scala/pull/3726#issuecomment-42861780). @@ -55,6 +59,48 @@ object AsmUtils { node } + def readClass(filename: String): ClassNode = readClass(classBytes(filename)) + + def classBytes(file: String): Array[Byte] = { + val f = new java.io.RandomAccessFile(file, "r") + val bytes = new Array[Byte](f.length.toInt) + f.read(bytes) + bytes + } + + def classFromBytes(bytes: Array[Byte]): ClassNode = { + val node = new ClassNode() + new ClassReader(bytes).accept(node, ClassReader.SKIP_DEBUG | ClassReader.SKIP_FRAMES) + + node + } + +// def main(args: Array[String]): Unit = println(textify(sortedClassRead(classBytes(args.head)))) + + def sortClassMembers(node: ClassNode): node.type = { + node.fields.sort(_.name compareTo _.name) + node.methods.sort(_.name compareTo _.name) + node + } + + // drop ScalaSig annotation and class attributes + def zapScalaClassAttrs(node: ClassNode): node.type = { + if (node.visibleAnnotations != null) + node.visibleAnnotations = node.visibleAnnotations.asScala.filterNot(a => a == null || a.desc.contains("Lscala/reflect/ScalaSignature")).asJava + + node.attrs = null + node + } + + def main(args: Array[String]): Unit = args.par.foreach { classFileName => + val node = zapScalaClassAttrs(sortClassMembers(classFromBytes(classBytes(classFileName)))) + + val pw = new PrintWriter(classFileName + ".asm") + val trace = new TraceClassVisitor(pw) + node.accept(trace) + pw.close() + } + /** * Returns a human-readable representation of the cnode ClassNode. */ @@ -115,12 +161,12 @@ object AsmUtils { * Run ASM's CheckClassAdapter over a class. Returns None if no problem is found, otherwise * Some(msg) with the verifier's error message. */ - def checkClass(classNode: ClassNode): Option[String] = { + def checkClass(classNode: ClassNode, dumpNonErroneous: Boolean = false): Option[String] = { val cw = new ClassWriter(ClassWriter.COMPUTE_MAXS) classNode.accept(cw) val sw = new StringWriter() val pw = new PrintWriter(sw) - CheckClassAdapter.verify(new ClassReader(cw.toByteArray), false, pw) + CheckClassAdapter.verify(new ClassReader(cw.toByteArray), dumpNonErroneous, pw) val res = sw.toString if (res.isEmpty) None else Some(res) } diff --git a/src/compiler/scala/tools/nsc/backend/jvm/BCodeAsmCommon.scala b/src/compiler/scala/tools/nsc/backend/jvm/BCodeAsmCommon.scala deleted file mode 100644 index 93f5159f89..0000000000 --- a/src/compiler/scala/tools/nsc/backend/jvm/BCodeAsmCommon.scala +++ /dev/null @@ -1,465 +0,0 @@ -/* NSC -- new Scala compiler - * Copyright 2005-2014 LAMP/EPFL - * @author Martin Odersky - */ - -package scala.tools.nsc -package backend.jvm - -import scala.tools.nsc.Global -import scala.tools.nsc.backend.jvm.BTypes.{InternalName, MethodInlineInfo, InlineInfo} -import BackendReporting.ClassSymbolInfoFailureSI9111 -import scala.tools.asm - -/** - * This trait contains code shared between GenBCode and GenASM that depends on types defined in - * the compiler cake (Global). - */ -final class BCodeAsmCommon[G <: Global](val global: G) { - import global._ - import definitions._ - - val ExcludedForwarderFlags = { - import scala.tools.nsc.symtab.Flags._ - // Should include DEFERRED but this breaks findMember. - SPECIALIZED | LIFTED | PROTECTED | STATIC | EXPANDEDNAME | BridgeAndPrivateFlags | MACRO - } - - /** - * True for classes generated by the Scala compiler that are considered top-level in terms of - * the InnerClass / EnclosingMethod classfile attributes. See comment in BTypes. - */ - def considerAsTopLevelImplementationArtifact(classSym: Symbol) = { - classSym.isImplClass || classSym.isSpecialized - } - - /** - * Cache the value of delambdafy == "inline" for each run. We need to query this value many - * times, so caching makes sense. - */ - object delambdafyInline { - private var runId = -1 - private var value = false - - def apply(): Boolean = { - if (runId != global.currentRunId) { - runId = global.currentRunId - value = settings.Ydelambdafy.value == "inline" - } - value - } - } - - /** - * True if `classSym` is an anonymous class or a local class. I.e., false if `classSym` is a - * member class. This method is used to decide if we should emit an EnclosingMethod attribute. - * It is also used to decide whether the "owner" field in the InnerClass attribute should be - * null. - */ - def isAnonymousOrLocalClass(classSym: Symbol): Boolean = { - assert(classSym.isClass, s"not a class: $classSym") - val r = exitingPickler(classSym.isAnonymousClass) || !classSym.originalOwner.isClass - if (r && settings.Ybackend.value == "GenBCode") { - // this assertion only holds in GenBCode. lambda lift renames symbols and may accidentally - // introduce `$lambda` into a class name, making `isDelambdafyFunction` true. under GenBCode - // we prevent this, see `nonAnon` in LambdaLift. - // phase travel necessary: after flatten, the name includes the name of outer classes. - // if some outer name contains $lambda, a non-lambda class is considered lambda. - assert(exitingPickler(!classSym.isDelambdafyFunction), classSym.name) - } - r - } - - /** - * The next enclosing definition in the source structure. Includes anonymous function classes - * under delambdafy:inline, even though they are only generated during UnCurry. - */ - def nextEnclosing(sym: Symbol): Symbol = { - val origOwner = sym.originalOwner - // phase travel necessary: after flatten, the name includes the name of outer classes. - // if some outer name contains $anon, a non-anon class is considered anon. - if (delambdafyInline() && sym.rawowner.isAnonymousFunction) { - // SI-9105: special handling for anonymous functions under delambdafy:inline. - // - // class C { def t = () => { def f { class Z } } } - // - // class C { def t = byNameMethod { def f { class Z } } } - // - // In both examples, the method f lambda-lifted into the anonfun class. - // - // In both examples, the enclosing method of Z is f, the enclosing class is the anonfun. - // So nextEnclosing needs to return the following chain: Z - f - anonFunClassSym - ... - // - // In the first example, the initial owner of f is a TermSymbol named "$anonfun" (note: not the anonFunClassSym!) - // In the second, the initial owner of f is t (no anon fun term symbol for by-name args!). - // - // In both cases, the rawowner of class Z is the anonFunClassSym. So the check in the `if` - // above makes sure we don't jump over the anonymous function in the by-name argument case. - // - // However, we cannot directly return the rawowner: if `sym` is Z, we need to include method f - // in the result. This is done by comparing the rawowners (read: lambdalift-targets) of `sym` - // and `sym.originalOwner`: if they are the same, then the originalOwner is "in between", and - // we need to return it. - // If the rawowners are different, the symbol was not in between. In the first example, the - // originalOwner of `f` is the anonfun-term-symbol, whose rawowner is C. So the nextEnclosing - // of `f` is its rawowner, the anonFunClassSym. - // - // In delambdafy:method we don't have that problem. The f method is lambda-lifted into C, - // not into the anonymous function class. The originalOwner chain is Z - f - C. - if (sym.originalOwner.rawowner == sym.rawowner) sym.originalOwner - else sym.rawowner - } else { - origOwner - } - } - - def nextEnclosingClass(sym: Symbol): Symbol = { - if (sym.isClass) sym - else nextEnclosingClass(nextEnclosing(sym)) - } - - def classOriginallyNestedInClass(nestedClass: Symbol, enclosingClass: Symbol) ={ - nextEnclosingClass(nextEnclosing(nestedClass)) == enclosingClass - } - - /** - * Returns the enclosing method for non-member classes. In the following example - * - * class A { - * def f = { - * class B { - * class C - * } - * } - * } - * - * the method returns Some(f) for B, but None for C, because C is a member class. For non-member - * classes that are not enclosed by a method, it returns None: - * - * class A { - * { class B } - * } - * - * In this case, for B, we return None. - * - * The EnclosingMethod attribute needs to be added to non-member classes (see doc in BTypes). - * This is a source-level property, so we need to use the originalOwner chain to reconstruct it. - */ - private def enclosingMethodForEnclosingMethodAttribute(classSym: Symbol): Option[Symbol] = { - assert(classSym.isClass, classSym) - - def doesNotExist(method: Symbol) = { - // (1) SI-9124, some trait methods don't exist in the generated interface. see comment in BTypes. - // (2) Value classes. Member methods of value classes exist in the generated box class. However, - // nested methods lifted into a value class are moved to the companion object and don't exist - // in the value class itself. We can identify such nested methods: the initial enclosing class - // is a value class, but the current owner is some other class (the module class). - method.owner.isTrait && method.isImplOnly || { // (1) - val enclCls = nextEnclosingClass(method) - exitingPickler(enclCls.isDerivedValueClass) && method.owner != enclCls // (2) - } - } - - def enclosingMethod(sym: Symbol): Option[Symbol] = { - if (sym.isClass || sym == NoSymbol) None - else if (sym.isMethod) { - if (doesNotExist(sym)) None else Some(sym) - } - else enclosingMethod(nextEnclosing(sym)) - } - enclosingMethod(nextEnclosing(classSym)) - } - - /** - * The enclosing class for emitting the EnclosingMethod attribute. Since this is a source-level - * property, this method looks at the originalOwner chain. See doc in BTypes. - */ - private def enclosingClassForEnclosingMethodAttribute(classSym: Symbol): Symbol = { - assert(classSym.isClass, classSym) - val r = nextEnclosingClass(nextEnclosing(classSym)) - // this should be an assertion, but we are more cautious for now as it was introduced before the 2.11.6 minor release - if (considerAsTopLevelImplementationArtifact(r)) devWarning(s"enclosing class of $classSym should not be an implementation artifact class: $r") - r - } - - final case class EnclosingMethodEntry(owner: String, name: String, methodDescriptor: String) - - /** - * Data for emitting an EnclosingMethod attribute. None if `classSym` is a member class (not - * an anonymous or local class). See doc in BTypes. - * - * The class is parametrized by two functions to obtain a bytecode class descriptor for a class - * symbol, and to obtain a method signature descriptor fro a method symbol. These function depend - * on the implementation of GenASM / GenBCode, so they need to be passed in. - */ - def enclosingMethodAttribute(classSym: Symbol, classDesc: Symbol => String, methodDesc: Symbol => String): Option[EnclosingMethodEntry] = { - // trait impl classes are always top-level, see comment in BTypes - if (isAnonymousOrLocalClass(classSym) && !considerAsTopLevelImplementationArtifact(classSym)) { - val enclosingClass = enclosingClassForEnclosingMethodAttribute(classSym) - val methodOpt = enclosingMethodForEnclosingMethodAttribute(classSym) match { - case some @ Some(m) => - if (m.owner != enclosingClass) { - // This should never happen. In case it does, it prevents emitting an invalid - // EnclosingMethod attribute: if the attribute specifies an enclosing method, - // it needs to exist in the specified enclosing class. - devWarning(s"the owner of the enclosing method ${m.locationString} should be the same as the enclosing class $enclosingClass") - None - } else some - case none => none - } - Some(EnclosingMethodEntry( - classDesc(enclosingClass), - methodOpt.map(_.javaSimpleName.toString).orNull, - methodOpt.map(methodDesc).orNull)) - } else { - None - } - } - - /** - * This is basically a re-implementation of sym.isStaticOwner, but using the originalOwner chain. - * - * The problem is that we are interested in a source-level property. Various phases changed the - * symbol's properties in the meantime, mostly lambdalift modified (destructively) the owner. - * Therefore, `sym.isStatic` is not what we want. For example, in - * object T { def f { object U } } - * the owner of U is T, so UModuleClass.isStatic is true. Phase travel does not help here. - */ - def isOriginallyStaticOwner(sym: Symbol): Boolean = { - sym.isPackageClass || sym.isModuleClass && isOriginallyStaticOwner(sym.originalOwner) - } - - /** - * Reconstruct the classfile flags from a Java defined class symbol. - * - * The implementation of this method is slightly different that `javaFlags` in BTypesFromSymbols. - * The javaFlags method is primarily used to map Scala symbol flags to sensible classfile flags - * that are used in the generated classfiles. For example, all classes emitted by the Scala - * compiler have ACC_PUBLIC. - * - * When building a [[ClassBType]] from a Java class symbol, the flags in the type's `info` have - * to correspond exactly to the flags in the classfile. For example, if the class is package - * protected (i.e., it doesn't have the ACC_PUBLIC flag), this needs to be reflected in the - * ClassBType. For example, the inliner needs the correct flags for access checks. - * - * Class flags are listed here: - * https://docs.oracle.com/javase/specs/jvms/se7/html/jvms-4.html#jvms-4.1-200-E.1 - */ - def javaClassfileFlags(classSym: Symbol): Int = { - assert(classSym.isJava, s"Expected Java class symbol, got ${classSym.fullName}") - import asm.Opcodes._ - def enumFlags = ACC_ENUM | { - // Java enums have the `ACC_ABSTRACT` flag if they have a deferred method. - // We cannot trust `hasAbstractFlag`: the ClassfileParser adds `ABSTRACT` and `SEALED` to all - // Java enums for exhaustiveness checking. - val hasAbstractMethod = classSym.info.decls.exists(s => s.isMethod && s.isDeferred) - if (hasAbstractMethod) ACC_ABSTRACT else 0 - } - GenBCode.mkFlags( - // SI-9393: the classfile / java source parser make java annotation symbols look like classes. - // here we recover the actual classfile flags. - if (classSym.hasJavaAnnotationFlag) ACC_ANNOTATION | ACC_INTERFACE | ACC_ABSTRACT else 0, - if (classSym.isPublic) ACC_PUBLIC else 0, - if (classSym.isFinal) ACC_FINAL else 0, - // see the link above. javac does the same: ACC_SUPER for all classes, but not interfaces. - if (classSym.isInterface) ACC_INTERFACE else ACC_SUPER, - // for Java enums, we cannot trust `hasAbstractFlag` (see comment in enumFlags) - if (!classSym.hasJavaEnumFlag && classSym.hasAbstractFlag) ACC_ABSTRACT else 0, - if (classSym.isArtifact) ACC_SYNTHETIC else 0, - if (classSym.hasJavaEnumFlag) enumFlags else 0 - ) - } - - /** - * The member classes of a class symbol. Note that the result of this method depends on the - * current phase, for example, after lambdalift, all local classes become member of the enclosing - * class. - * - * Impl classes are always considered top-level, see comment in BTypes. - */ - def memberClassesForInnerClassTable(classSymbol: Symbol): List[Symbol] = classSymbol.info.decls.collect({ - case sym if sym.isClass && !considerAsTopLevelImplementationArtifact(sym) => - sym - case sym if sym.isModule && !considerAsTopLevelImplementationArtifact(sym) => // impl classes get the lateMODULE flag in mixin - val r = exitingPickler(sym.moduleClass) - assert(r != NoSymbol, sym.fullLocationString) - r - })(collection.breakOut) - - lazy val AnnotationRetentionPolicyModule = AnnotationRetentionPolicyAttr.companionModule - lazy val AnnotationRetentionPolicySourceValue = AnnotationRetentionPolicyModule.tpe.member(TermName("SOURCE")) - lazy val AnnotationRetentionPolicyClassValue = AnnotationRetentionPolicyModule.tpe.member(TermName("CLASS")) - lazy val AnnotationRetentionPolicyRuntimeValue = AnnotationRetentionPolicyModule.tpe.member(TermName("RUNTIME")) - - /** Whether an annotation should be emitted as a Java annotation - * .initialize: if 'annot' is read from pickle, atp might be uninitialized - */ - def shouldEmitAnnotation(annot: AnnotationInfo) = { - annot.symbol.initialize.isJavaDefined && - annot.matches(ClassfileAnnotationClass) && - retentionPolicyOf(annot) != AnnotationRetentionPolicySourceValue && - annot.args.isEmpty - } - - def isRuntimeVisible(annot: AnnotationInfo): Boolean = { - annot.atp.typeSymbol.getAnnotation(AnnotationRetentionAttr) match { - case Some(retentionAnnot) => - retentionAnnot.assocs.contains(nme.value -> LiteralAnnotArg(Constant(AnnotationRetentionPolicyRuntimeValue))) - case _ => - // SI-8926: if the annotation class symbol doesn't have a @RetentionPolicy annotation, the - // annotation is emitted with visibility `RUNTIME` - true - } - } - - private def retentionPolicyOf(annot: AnnotationInfo): Symbol = - annot.atp.typeSymbol.getAnnotation(AnnotationRetentionAttr).map(_.assocs).flatMap(assoc => - assoc.collectFirst { - case (`nme`.value, LiteralAnnotArg(Constant(value: Symbol))) => value - }).getOrElse(AnnotationRetentionPolicyClassValue) - - def implementedInterfaces(classSym: Symbol): List[Symbol] = { - // Additional interface parents based on annotations and other cues - def newParentForAnnotation(ann: AnnotationInfo): Option[Type] = ann.symbol match { - case RemoteAttr => Some(RemoteInterfaceClass.tpe) - case _ => None - } - - // SI-9393: java annotations are interfaces, but the classfile / java source parsers make them look like classes. - def isInterfaceOrTrait(sym: Symbol) = sym.isInterface || sym.isTrait || sym.hasJavaAnnotationFlag - - val classParents = { - val parents = classSym.info.parents - // SI-9393: the classfile / java source parsers add Annotation and ClassfileAnnotation to the - // parents of a java annotations. undo this for the backend (where we need classfile-level information). - if (classSym.hasJavaAnnotationFlag) parents.filterNot(c => c.typeSymbol == ClassfileAnnotationClass || c.typeSymbol == AnnotationClass) - else parents - } - - val allParents = classParents ++ classSym.annotations.flatMap(newParentForAnnotation) - - // We keep the superClass when computing minimizeParents to eliminate more interfaces. - // Example: T can be eliminated from D - // trait T - // class C extends T - // class D extends C with T - val interfaces = erasure.minimizeParents(allParents) match { - case superClass :: ifs if !isInterfaceOrTrait(superClass.typeSymbol) => - ifs - case ifs => - // minimizeParents removes the superclass if it's redundant, for example: - // trait A - // class C extends Object with A // minimizeParents removes Object - ifs - } - interfaces.map(_.typeSymbol) - } - - /** - * This is a hack to work around SI-9111. The completer of `methodSym` may report type errors. We - * cannot change the typer context of the completer at this point and make it silent: the context - * captured when creating the completer in the namer. However, we can temporarily replace - * global.reporter (it's a var) to store errors. - */ - def completeSilentlyAndCheckErroneous(sym: Symbol): Boolean = { - if (sym.hasCompleteInfo) false - else { - val originalReporter = global.reporter - val storeReporter = new reporters.StoreReporter() - global.reporter = storeReporter - try { - sym.info - } finally { - global.reporter = originalReporter - } - sym.isErroneous - } - } - - /** - * Build the [[InlineInfo]] for a class symbol. - */ - def buildInlineInfoFromClassSymbol(classSym: Symbol, classSymToInternalName: Symbol => InternalName, methodSymToDescriptor: Symbol => String): InlineInfo = { - val traitSelfType = if (classSym.isTrait && !classSym.isImplClass) { - // The mixin phase uses typeOfThis for the self parameter in implementation class methods. - val selfSym = classSym.typeOfThis.typeSymbol - if (selfSym != classSym) Some(classSymToInternalName(selfSym)) else None - } else { - None - } - - val isEffectivelyFinal = classSym.isEffectivelyFinal - - var warning = Option.empty[ClassSymbolInfoFailureSI9111] - - // Primitive methods cannot be inlined, so there's no point in building a MethodInlineInfo. Also, some - // primitive methods (e.g., `isInstanceOf`) have non-erased types, which confuses [[typeToBType]]. - val methodInlineInfos = classSym.info.decls.iterator.filter(m => m.isMethod && !scalaPrimitives.isPrimitive(m)).flatMap({ - case methodSym => - if (completeSilentlyAndCheckErroneous(methodSym)) { - // Happens due to SI-9111. Just don't provide any MethodInlineInfo for that method, we don't need fail the compiler. - if (!classSym.isJavaDefined) devWarning("SI-9111 should only be possible for Java classes") - warning = Some(ClassSymbolInfoFailureSI9111(classSym.fullName)) - None - } else { - val name = methodSym.javaSimpleName.toString // same as in genDefDef - val signature = name + methodSymToDescriptor(methodSym) - - // Some detours are required here because of changing flags (lateDEFERRED, lateMODULE): - // 1. Why the phase travel? Concrete trait methods obtain the lateDEFERRED flag in Mixin. - // This makes isEffectivelyFinalOrNotOverridden false, which would prevent non-final - // but non-overridden methods of sealed traits from being inlined. - // 2. Why the special case for `classSym.isImplClass`? Impl class symbols obtain the - // lateMODULE flag during Mixin. During the phase travel to exitingPickler, the late - // flag is ignored. The members are therefore not isEffectivelyFinal (their owner - // is not a module). Since we know that all impl class members are static, we can - // just take the shortcut. - val effectivelyFinal = classSym.isImplClass || exitingPickler(methodSym.isEffectivelyFinalOrNotOverridden) - - // Identify trait interface methods that have a static implementation in the implementation - // class. Invocations of these methods can be re-wrired directly to the static implementation - // if they are final or the receiver is known. - // - // Using `erasure.needsImplMethod` is not enough: it keeps field accessors, module getters - // and super accessors. When AddInterfaces creates the impl class, these methods are - // initially added to it. - // - // The mixin phase later on filters out most of these members from the impl class (see - // Mixin.isImplementedStatically). However, accessors for concrete lazy vals remain in the - // impl class after mixin. So the filter in mixin is not exactly what we need here (we - // want to identify concrete trait methods, not any accessors). So we check some symbol - // properties manually. - val traitMethodWithStaticImplementation = { - import symtab.Flags._ - classSym.isTrait && !classSym.isImplClass && - erasure.needsImplMethod(methodSym) && - !methodSym.isModule && - !(methodSym hasFlag (ACCESSOR | SUPERACCESSOR)) - } - - val info = MethodInlineInfo( - effectivelyFinal = effectivelyFinal, - traitMethodWithStaticImplementation = traitMethodWithStaticImplementation, - annotatedInline = methodSym.hasAnnotation(ScalaInlineClass), - annotatedNoInline = methodSym.hasAnnotation(ScalaNoInlineClass) - ) - Some((signature, info)) - } - }).toMap - - InlineInfo(traitSelfType, isEffectivelyFinal, methodInlineInfos, warning) - } -} - -object BCodeAsmCommon { - /** - * Valid flags for InnerClass attribute entry. - * See http://docs.oracle.com/javase/specs/jvms/se8/html/jvms-4.html#jvms-4.7.6 - */ - val INNER_CLASSES_FLAGS = { - asm.Opcodes.ACC_PUBLIC | asm.Opcodes.ACC_PRIVATE | asm.Opcodes.ACC_PROTECTED | - asm.Opcodes.ACC_STATIC | asm.Opcodes.ACC_FINAL | asm.Opcodes.ACC_INTERFACE | - asm.Opcodes.ACC_ABSTRACT | asm.Opcodes.ACC_SYNTHETIC | asm.Opcodes.ACC_ANNOTATION | - asm.Opcodes.ACC_ENUM - } -} diff --git a/src/compiler/scala/tools/nsc/backend/jvm/BCodeBodyBuilder.scala b/src/compiler/scala/tools/nsc/backend/jvm/BCodeBodyBuilder.scala index 416628d5ba..37dea477c6 100644 --- a/src/compiler/scala/tools/nsc/backend/jvm/BCodeBodyBuilder.scala +++ b/src/compiler/scala/tools/nsc/backend/jvm/BCodeBodyBuilder.scala @@ -11,10 +11,13 @@ package jvm import scala.annotation.switch import scala.reflect.internal.Flags - import scala.tools.asm import GenBCode._ import BackendReporting._ +import scala.collection.mutable +import scala.tools.asm.Opcodes +import scala.tools.asm.tree.{MethodInsnNode, MethodNode} +import scala.tools.nsc.backend.jvm.BCodeHelpers.{InvokeStyle, TestOp} /* * @@ -26,24 +29,12 @@ abstract class BCodeBodyBuilder extends BCodeSkelBuilder { import global._ import definitions._ import bTypes._ - import bCodeICodeCommon._ import coreBTypes._ /* * Functionality to build the body of ASM MethodNode, except for `synchronized` and `try` expressions. */ abstract class PlainBodyBuilder(cunit: CompilationUnit) extends PlainSkelBuilder(cunit) { - import icodes.TestOp - import icodes.opcodes.InvokeStyle - - /* If the selector type has a member with the right name, - * it is the host class; otherwise the symbol's owner. - */ - def findHostClass(selector: Type, sym: Symbol) = selector member sym.name match { - case NoSymbol => debuglog(s"Rejecting $selector as host class for $sym") ; sym.owner - case _ => selector.typeSymbol - } - /* ---------------- helper utils for generating methods and code ---------------- */ def emit(opc: Int) { mnode.visitInsn(opc) } @@ -71,12 +62,14 @@ abstract class BCodeBodyBuilder extends BCodeSkelBuilder { def genStat(tree: Tree) { lineNumber(tree) tree match { - case Assign(lhs @ Select(_, _), rhs) => + case Assign(lhs @ Select(qual, _), rhs) => val isStatic = lhs.symbol.isStaticMember if (!isStatic) { genLoadQualifier(lhs) } genLoad(rhs, symInfoTK(lhs.symbol)) lineNumber(tree) - fieldStore(lhs.symbol) + // receiverClass is used in the bytecode to access the field. using sym.owner may lead to IllegalAccessError, SI-4283 + val receiverClass = qual.tpe.typeSymbol + fieldStore(lhs.symbol, receiverClass) case Assign(lhs, rhs) => val s = lhs.symbol @@ -94,12 +87,12 @@ abstract class BCodeBodyBuilder extends BCodeSkelBuilder { val thrownKind = tpeTK(expr) // `throw null` is valid although scala.Null (as defined in src/library-aux) isn't a subtype of Throwable. // Similarly for scala.Nothing (again, as defined in src/library-aux). - assert(thrownKind.isNullType || thrownKind.isNothingType || thrownKind.asClassBType.isSubtypeOf(ThrowableReference).get) + assert(thrownKind.isNullType || thrownKind.isNothingType || thrownKind.asClassBType.isSubtypeOf(jlThrowableRef).get) genLoad(expr, thrownKind) lineNumber(expr) emit(asm.Opcodes.ATHROW) // ICode enters here into enterIgnoreMode, we'll rely instead on DCE at ClassNode level. - RT_NOTHING // always returns the same, the invoker should know :) + srNothingRef // always returns the same, the invoker should know :) } /* Generate code for primitive arithmetic operations. */ @@ -119,21 +112,22 @@ abstract class BCodeBodyBuilder extends BCodeSkelBuilder { code match { case POS => () // nothing case NEG => bc.neg(resKind) - case NOT => bc.genPrimitiveArithmetic(icodes.NOT, resKind) + case NOT => bc.genPrimitiveNot(resKind) case _ => abort(s"Unknown unary operation: ${fun.symbol.fullName} code: $code") } // binary operation case rarg :: Nil => - resKind = tpeTK(larg).maxType(tpeTK(rarg)) - if (scalaPrimitives.isShiftOp(code) || scalaPrimitives.isBitwiseOp(code)) { + val isShiftOp = scalaPrimitives.isShiftOp(code) + resKind = tpeTK(larg).maxType(if (isShiftOp) INT else tpeTK(rarg)) + + if (isShiftOp || scalaPrimitives.isBitwiseOp(code)) { assert(resKind.isIntegralType || (resKind == BOOL), s"$resKind incompatible with arithmetic modulo operation.") } genLoad(larg, resKind) - genLoad(rarg, // check .NET size of shift arguments! - if (scalaPrimitives.isShiftOp(code)) INT else resKind) + genLoad(rarg, if (isShiftOp) INT else resKind) (code: @switch) match { case ADD => bc add resKind @@ -171,21 +165,13 @@ abstract class BCodeBodyBuilder extends BCodeSkelBuilder { genLoad(args.head, INT) generatedType = k.asArrayBType.componentType bc.aload(elementType) - } - else if (scalaPrimitives.isArraySet(code)) { - args match { - case a1 :: a2 :: Nil => - genLoad(a1, INT) - genLoad(a2) - // the following line should really be here, but because of bugs in erasure - // we pretend we generate whatever type is expected from us. - //generatedType = UNIT - bc.astore(elementType) - case _ => - abort(s"Too many arguments for array set operation: $tree") - } - } - else { + } else if (scalaPrimitives.isArraySet(code)) { + val List(a1, a2) = args + genLoad(a1, INT) + genLoad(a2, elementType) + generatedType = UNIT + bc.astore(elementType) + } else { generatedType = INT emit(asm.Opcodes.ARRAYLENGTH) } @@ -203,14 +189,14 @@ abstract class BCodeBodyBuilder extends BCodeSkelBuilder { val hasElse = !elsep.isEmpty val postIf = if (hasElse) new asm.Label else failure - genCond(condp, success, failure) + genCond(condp, success, failure, targetIfNoJump = success) + markProgramPoint(success) val thenKind = tpeTK(thenp) val elseKind = if (!hasElse) UNIT else tpeTK(elsep) def hasUnitBranch = (thenKind == UNIT || elseKind == UNIT) val resKind = if (hasUnitBranch) UNIT else tpeTK(tree) - markProgramPoint(success) genLoad(thenp, resKind) if (hasElse) { bc goTo postIf } markProgramPoint(failure) @@ -235,14 +221,14 @@ abstract class BCodeBodyBuilder extends BCodeSkelBuilder { else if (isArrayOp(code)) genArrayOp(tree, code, expectedType) else if (isLogicalOp(code) || isComparisonOp(code)) { val success, failure, after = new asm.Label - genCond(tree, success, failure) + genCond(tree, success, failure, targetIfNoJump = success) // success block - markProgramPoint(success) - bc boolconst true - bc goTo after + markProgramPoint(success) + bc boolconst true + bc goTo after // failure block - markProgramPoint(failure) - bc boolconst false + markProgramPoint(failure) + bc boolconst false // after markProgramPoint(after) @@ -311,6 +297,15 @@ abstract class BCodeBodyBuilder extends BCodeSkelBuilder { case app : Apply => generatedType = genApply(app, expectedType) + case app @ ApplyDynamic(qual, Literal(Constant(bootstrapMethodRef: Symbol)) :: staticAndDynamicArgs) => + val numStaticArgs = bootstrapMethodRef.paramss.head.size - 3 /*JVM provided args*/ + val (staticArgs, dynamicArgs) = staticAndDynamicArgs.splitAt(numStaticArgs) + val bootstrapDescriptor = staticHandleFromSymbol(bootstrapMethodRef) + val bootstrapArgs = staticArgs.map({case t @ Literal(c: Constant) => bootstrapMethodArg(c, t.pos)}) + val descriptor = methodBTypeFromMethodType(qual.symbol.info, false) + genLoadArguments(dynamicArgs, qual.symbol.info.params.map(param => typeToBType(param.info))) + mnode.visitInvokeDynamicInsn(qual.symbol.name.encoded, descriptor.descriptor, bootstrapDescriptor, bootstrapArgs : _*) + case ApplyDynamic(qual, args) => sys.error("No invokedynamic support yet.") case This(qual) => @@ -323,7 +318,7 @@ abstract class BCodeBodyBuilder extends BCodeSkelBuilder { else { mnode.visitVarInsn(asm.Opcodes.ALOAD, 0) generatedType = - if (tree.symbol == ArrayClass) ObjectReference + if (tree.symbol == ArrayClass) ObjectRef else classBTypeFromSymbol(claszSymbol) } @@ -331,26 +326,22 @@ abstract class BCodeBodyBuilder extends BCodeSkelBuilder { assert(tree.symbol.isModule, s"Selection of non-module from empty package: $tree sym: ${tree.symbol} at: ${tree.pos}") genLoadModule(tree) - case Select(qualifier, selector) => + case Select(qualifier, _) => val sym = tree.symbol generatedType = symInfoTK(sym) - val hostClass = findHostClass(qualifier.tpe, sym) - debuglog(s"Host class of $sym with qual $qualifier (${qualifier.tpe}) is $hostClass") val qualSafeToElide = treeInfo isQualifierSafeToElide qualifier - def genLoadQualUnlessElidable() { if (!qualSafeToElide) { genLoadQualifier(tree) } } - + // receiverClass is used in the bytecode to access the field. using sym.owner may lead to IllegalAccessError, SI-4283 + def receiverClass = qualifier.tpe.typeSymbol if (sym.isModule) { genLoadQualUnlessElidable() genLoadModule(tree) - } - else if (sym.isStaticMember) { + } else if (sym.isStaticMember) { genLoadQualUnlessElidable() - fieldLoad(sym, hostClass) - } - else { + fieldLoad(sym, receiverClass) + } else { genLoadQualifier(tree) - fieldLoad(sym, hostClass) + fieldLoad(sym, receiverClass) } case Ident(name) => @@ -366,7 +357,7 @@ abstract class BCodeBodyBuilder extends BCodeSkelBuilder { if (value.tag != UnitTag) (value.tag, expectedType) match { case (IntTag, LONG ) => bc.lconst(value.longValue); generatedType = LONG case (FloatTag, DOUBLE) => bc.dconst(value.doubleValue); generatedType = DOUBLE - case (NullTag, _ ) => bc.emit(asm.Opcodes.ACONST_NULL); generatedType = RT_NULL + case (NullTag, _ ) => bc.emit(asm.Opcodes.ACONST_NULL); generatedType = srNullRef case _ => genConstant(value); generatedType = tpeTK(tree) } @@ -403,24 +394,18 @@ abstract class BCodeBodyBuilder extends BCodeSkelBuilder { /* * must-single-thread */ - def fieldLoad( field: Symbol, hostClass: Symbol = null) { - fieldOp(field, isLoad = true, hostClass) - } + def fieldLoad(field: Symbol, hostClass: Symbol): Unit = fieldOp(field, isLoad = true, hostClass) + /* * must-single-thread */ - def fieldStore(field: Symbol, hostClass: Symbol = null) { - fieldOp(field, isLoad = false, hostClass) - } + def fieldStore(field: Symbol, hostClass: Symbol): Unit = fieldOp(field, isLoad = false, hostClass) /* * must-single-thread */ - private def fieldOp(field: Symbol, isLoad: Boolean, hostClass: Symbol) { - // LOAD_FIELD.hostClass , CALL_METHOD.hostClass , and #4283 - val owner = - if (hostClass == null) internalName(field.owner) - else internalName(hostClass) + private def fieldOp(field: Symbol, isLoad: Boolean, hostClass: Symbol): Unit = { + val owner = internalName(if (hostClass == null) field.owner else hostClass) val fieldJName = field.javaSimpleName.toString val fieldDescr = symInfoTK(field).descriptor val isStatic = field.isStaticMember @@ -428,7 +413,6 @@ abstract class BCodeBodyBuilder extends BCodeSkelBuilder { if (isLoad) { if (isStatic) asm.Opcodes.GETSTATIC else asm.Opcodes.GETFIELD } else { if (isStatic) asm.Opcodes.PUTSTATIC else asm.Opcodes.PUTFIELD } mnode.visitFieldInsn(opc, owner, fieldJName, fieldDescr) - } // ---------------- emitting constant values ---------------- @@ -461,19 +445,16 @@ abstract class BCodeBodyBuilder extends BCodeSkelBuilder { case NullTag => emit(asm.Opcodes.ACONST_NULL) case ClazzTag => - val toPush: BType = { - toTypeKind(const.typeValue) match { - case kind: PrimitiveBType => boxedClassOfPrimitive(kind) - case kind => kind - } - } - mnode.visitLdcInsn(toPush.toASMType) + val tp = typeToBType(const.typeValue) + // classOf[Int] is transformed to Integer.TYPE by CleanUp + assert(!tp.isPrimitive, s"expected class type in classOf[T], found primitive type $tp") + mnode.visitLdcInsn(tp.toASMType) case EnumTag => val sym = const.symbolValue val ownerName = internalName(sym.owner) val fieldName = sym.javaSimpleName.toString - val fieldDesc = toTypeKind(sym.tpe.underlying).descriptor + val fieldDesc = typeToBType(sym.tpe.underlying).descriptor mnode.visitFieldInsn( asm.Opcodes.GETSTATIC, ownerName, @@ -507,16 +488,11 @@ abstract class BCodeBodyBuilder extends BCodeSkelBuilder { bc emitRETURN returnType case nextCleanup :: rest => if (saveReturnValue) { - if (insideCleanupBlock) { - reporter.warning(r.pos, "Return statement found in finally-clause, discarding its return-value in favor of that of a more deeply nested return.") - bc drop returnType - } else { - // regarding return value, the protocol is: in place of a `return-stmt`, a sequence of `adapt, store, jump` are inserted. - if (earlyReturnVar == null) { - earlyReturnVar = locals.makeLocal(returnType, "earlyReturnVar") - } - locals.store(earlyReturnVar) + // regarding return value, the protocol is: in place of a `return-stmt`, a sequence of `adapt, store, jump` are inserted. + if (earlyReturnVar == null) { + earlyReturnVar = locals.makeLocal(returnType, "earlyReturnVar") } + locals.store(earlyReturnVar) } bc goTo nextCleanup shouldEmitCleanup = true @@ -527,6 +503,7 @@ abstract class BCodeBodyBuilder extends BCodeSkelBuilder { private def genApply(app: Apply, expectedType: BType): BType = { var generatedType = expectedType lineNumber(app) + app match { case Apply(TypeApply(fun, targs), _) => @@ -551,8 +528,8 @@ abstract class BCodeBodyBuilder extends BCodeSkelBuilder { else if (l.isPrimitive) { bc drop l if (cast) { - mnode.visitTypeInsn(asm.Opcodes.NEW, classCastExceptionReference.internalName) - bc dup ObjectReference + mnode.visitTypeInsn(asm.Opcodes.NEW, jlClassCastExceptionRef.internalName) + bc dup ObjectRef emit(asm.Opcodes.ATHROW) } else { bc boolconst false @@ -574,19 +551,33 @@ abstract class BCodeBodyBuilder extends BCodeSkelBuilder { generatedType = genTypeApply() - // 'super' call: Note: since constructors are supposed to - // return an instance of what they construct, we have to take - // special care. On JVM they are 'void', and Scala forbids (syntactically) - // to call super constructors explicitly and/or use their 'returned' value. - // therefore, we can ignore this fact, and generate code that leaves nothing - // on the stack (contrary to what the type in the AST says). - case Apply(fun @ Select(Super(_, mix), _), args) => - val invokeStyle = icodes.opcodes.SuperCall(mix) - // if (fun.symbol.isConstructor) Static(true) else SuperCall(mix); + case Apply(fun @ Select(Super(_, _), _), args) => + def initModule() { + // we initialize the MODULE$ field immediately after the super ctor + if (!isModuleInitialized && + jMethodName == INSTANCE_CONSTRUCTOR_NAME && + fun.symbol.javaSimpleName.toString == INSTANCE_CONSTRUCTOR_NAME && + isStaticModuleClass(claszSymbol)) { + isModuleInitialized = true + mnode.visitVarInsn(asm.Opcodes.ALOAD, 0) + mnode.visitFieldInsn( + asm.Opcodes.PUTSTATIC, + thisBType.internalName, + strMODULE_INSTANCE_FIELD, + thisBType.descriptor + ) + } + } + // 'super' call: Note: since constructors are supposed to + // return an instance of what they construct, we have to take + // special care. On JVM they are 'void', and Scala forbids (syntactically) + // to call super constructors explicitly and/or use their 'returned' value. + // therefore, we can ignore this fact, and generate code that leaves nothing + // on the stack (contrary to what the type in the AST says). mnode.visitVarInsn(asm.Opcodes.ALOAD, 0) genLoadArguments(args, paramTKs(app)) - genCallMethod(fun.symbol, invokeStyle, app.pos) - generatedType = asmMethodType(fun.symbol).returnType + generatedType = genCallMethod(fun.symbol, InvokeStyle.Super, app.pos) + initModule() // 'new' constructor call: Note: since constructors are // thought to return an instance of what they construct, @@ -617,8 +608,8 @@ abstract class BCodeBodyBuilder extends BCodeSkelBuilder { } argsSize match { case 1 => bc newarray elemKind - case _ => - val descr = ('[' * argsSize) + elemKind.descriptor // denotes the same as: arrayN(elemKind, argsSize).descriptor + case _ => // this is currently dead code in Scalac, unlike in Dotty + val descr = ("[" * argsSize) + elemKind.descriptor // denotes the same as: arrayN(elemKind, argsSize).descriptor mnode.visitMultiANewArrayInsn(descr, argsSize) } @@ -627,7 +618,7 @@ abstract class BCodeBodyBuilder extends BCodeSkelBuilder { mnode.visitTypeInsn(asm.Opcodes.NEW, rt.internalName) bc dup generatedType genLoadArguments(args, paramTKs(app)) - genCallMethod(ctor, icodes.opcodes.Static(onInstance = true), app.pos) + genCallMethod(ctor, InvokeStyle.Special, app.pos) case _ => abort(s"Cannot instantiate $tpt of kind: $generatedType") @@ -635,85 +626,97 @@ abstract class BCodeBodyBuilder extends BCodeSkelBuilder { case Apply(fun, args) if app.hasAttachment[delambdafy.LambdaMetaFactoryCapable] => val attachment = app.attachments.get[delambdafy.LambdaMetaFactoryCapable].get genLoadArguments(args, paramTKs(app)) - genInvokeDynamicLambda(attachment.target, attachment.arity, attachment.functionalInterface) - generatedType = asmMethodType(fun.symbol).returnType + genInvokeDynamicLambda(attachment.target, attachment.arity, attachment.functionalInterface, attachment.sam, attachment.isSerializable, attachment.addScalaSerializableMarker) + generatedType = methodBTypeFromSymbol(fun.symbol).returnType - case Apply(fun @ _, List(expr)) if currentRun.runDefinitions.isBox(fun.symbol) => - val nativeKind = tpeTK(expr) + case Apply(fun, List(expr)) if currentRun.runDefinitions.isBox(fun.symbol) => + val nativeKind = typeToBType(fun.symbol.firstParam.info) genLoad(expr, nativeKind) - val MethodNameAndType(mname, methodType) = asmBoxTo(nativeKind) - bc.invokestatic(BoxesRunTime.internalName, mname, methodType.descriptor, app.pos) - generatedType = boxResultType(fun.symbol) // was toTypeKind(fun.symbol.tpe.resultType) + val MethodNameAndType(mname, methodType) = srBoxesRuntimeBoxToMethods(nativeKind) + bc.invokestatic(srBoxesRunTimeRef.internalName, mname, methodType.descriptor, itf = false, app.pos) + generatedType = boxResultType(fun.symbol) - case Apply(fun @ _, List(expr)) if currentRun.runDefinitions.isUnbox(fun.symbol) => + case Apply(fun, List(expr)) if currentRun.runDefinitions.isUnbox(fun.symbol) => genLoad(expr) - val boxType = unboxResultType(fun.symbol) // was toTypeKind(fun.symbol.owner.linkedClassOfClass.tpe) + val boxType = unboxResultType(fun.symbol) generatedType = boxType - val MethodNameAndType(mname, methodType) = asmUnboxTo(boxType) - bc.invokestatic(BoxesRunTime.internalName, mname, methodType.descriptor, app.pos) + val MethodNameAndType(mname, methodType) = srBoxesRuntimeUnboxToMethods(boxType) + bc.invokestatic(srBoxesRunTimeRef.internalName, mname, methodType.descriptor, itf = false, app.pos) case app @ Apply(fun, args) => val sym = fun.symbol - if (sym.isLabel) { // jump to a label + if (sym.isLabel) { // jump to a label genLoadLabelArguments(args, labelDef(sym), app.pos) bc goTo programPoint(sym) } else if (isPrimitive(sym)) { // primitive method call generatedType = genPrimitiveOp(app, expectedType) - } else { // normal method call - - def genNormalMethodCall() { - - val invokeStyle = - if (sym.isStaticMember) icodes.opcodes.Static(onInstance = false) - else if (sym.isPrivate || sym.isClassConstructor) icodes.opcodes.Static(onInstance = true) - else icodes.opcodes.Dynamic; - - if (invokeStyle.hasInstance) { - genLoadQualifier(fun) + } else { // normal method call + def isTraitSuperAccessorBodyCall = app.hasAttachment[UseInvokeSpecial.type] + val invokeStyle = + if (sym.isStaticMember) + InvokeStyle.Static + else if (sym.isPrivate || sym.isClassConstructor) InvokeStyle.Special + else if (isTraitSuperAccessorBodyCall) + InvokeStyle.Special + else InvokeStyle.Virtual + + if (invokeStyle.hasInstance) genLoadQualifier(fun) + genLoadArguments(args, paramTKs(app)) + + val Select(qual, _) = fun // fun is a Select, also checked in genLoadQualifier + if (sym == definitions.Array_clone) { + // Special-case Array.clone, introduced in 36ef60e. The goal is to generate this call + // as "[I.clone" instead of "java/lang/Object.clone". This is consistent with javac. + // Arrays have a public method `clone` (jls 10.7). + // + // The JVMS is not explicit about this, but that receiver type can be an array type + // descriptor (instead of a class internal name): + // invokevirtual #2; //Method "[I".clone:()Ljava/lang/Object + // + // Note that using `Object.clone()` would work as well, but only because the JVM + // relaxes protected access specifically if the receiver is an array: + // http://hg.openjdk.java.net/jdk8/jdk8/hotspot/file/87ee5ee27509/src/share/vm/interpreter/linkResolver.cpp#l439 + // Example: `class C { override def clone(): Object = "hi" }` + // Emitting `def f(c: C) = c.clone()` as `Object.clone()` gives a VerifyError. + val target: String = tpeTK(qual).asRefBType.classOrArrayType + val methodBType = methodBTypeFromSymbol(sym) + bc.invokevirtual(target, sym.javaSimpleName.toString, methodBType.descriptor, app.pos) + generatedType = methodBType.returnType + } else { + val receiverClass = if (!invokeStyle.isVirtual) null else { + // receiverClass is used in the bytecode to as the method receiver. using sym.owner + // may lead to IllegalAccessErrors, see 9954eaf / aladdin bug 455. + val qualSym = qual.tpe.typeSymbol + if (qualSym == ArrayClass) { + // For invocations like `Array(1).hashCode` or `.wait()`, use Object as receiver + // in the bytecode. Using the array descriptor (like we do for clone above) seems + // to work as well, but it seems safer not to change this. Javac also uses Object. + // Note that array apply/update/length are handled by isPrimitive (above). + assert(sym.owner == ObjectClass, s"unexpected array call: ${show(app)}") + ObjectClass + } else qualSym } - genLoadArguments(args, paramTKs(app)) - - // In "a couple cases", squirrel away a extra information (hostClass, targetTypeKind). TODO Document what "in a couple cases" refers to. - var hostClass: Symbol = null - var targetTypeKind: BType = null - fun match { - case Select(qual, _) => - val qualSym = findHostClass(qual.tpe, sym) - if (qualSym == ArrayClass) { - targetTypeKind = tpeTK(qual) - log(s"Stored target type kind for ${sym.fullName} as $targetTypeKind") - } - else { - hostClass = qualSym - if (qual.tpe.typeSymbol != qualSym) { - log(s"Precisified host class for $sym from ${qual.tpe.typeSymbol.fullName} to ${qualSym.fullName}") - } - } - - case _ => - } - if ((targetTypeKind != null) && (sym == definitions.Array_clone) && invokeStyle.isDynamic) { - // An invokevirtual points to a CONSTANT_Methodref_info which in turn points to a - // CONSTANT_Class_info of the receiver type. - // The JVMS is not explicit about this, but that receiver type may be an array type - // descriptor (instead of a class internal name): - // invokevirtual #2; //Method "[I".clone:()Ljava/lang/Object - val target: String = targetTypeKind.asRefBType.classOrArrayType - bc.invokevirtual(target, "clone", "()Ljava/lang/Object;", app.pos) - } - else { - genCallMethod(sym, invokeStyle, app.pos, hostClass) + generatedType = genCallMethod(sym, invokeStyle, app.pos, receiverClass) + + // Check if the Apply tree has an InlineAnnotatedAttachment, added by the typer + // for callsites marked `f(): @inline/noinline`. For nullary calls, the attachment + // is on the Select node (not on the Apply node added by UnCurry). + def recordInlineAnnotated(t: Tree): Unit = { + if (t.hasAttachment[InlineAnnotatedAttachment]) lastInsn match { + case m: MethodInsnNode => + if (app.hasAttachment[NoInlineCallsiteAttachment.type]) noInlineAnnotatedCallsites += m + else inlineAnnotatedCallsites += m + case _ => + } else t match { + case Apply(fun, _) => recordInlineAnnotated(fun) + case _ => + } } - - } // end of genNormalMethodCall() - - genNormalMethodCall() - - generatedType = asmMethodType(sym).returnType + recordInlineAnnotated(app) + } } - } generatedType @@ -767,7 +770,7 @@ abstract class BCodeBodyBuilder extends BCodeSkelBuilder { for (caze @ CaseDef(pat, guard, body) <- tree.cases) { assert(guard == EmptyTree, guard) val switchBlockPoint = new asm.Label - switchBlocks ::= (switchBlockPoint, body) + switchBlocks ::= ((switchBlockPoint, body)) pat match { case Literal(value) => flatKeys ::= value.intValue @@ -843,8 +846,7 @@ abstract class BCodeBodyBuilder extends BCodeSkelBuilder { * loading another throwable first). * * New (http://docs.oracle.com/javase/specs/jvms/se8/html/jvms-4.html#jvms-4.10.1) - * - Requires consistent stack map frames. GenBCode generates stack frames if -target:jvm-1.6 - * or higher. + * - Requires consistent stack map frames. GenBCode always generates stack frames. * - In practice: the ASM library computes stack map frames for us (ClassWriter). Emitting * correct frames after an ATHROW is probably complex, so ASM uses the following strategy: * - Every time when generating an ATHROW, a new basic block is started. @@ -866,10 +868,24 @@ abstract class BCodeBodyBuilder extends BCodeSkelBuilder { * emitted instruction was an ATHROW. As explained above, it is OK to emit a second ATHROW, * the verifiers will be happy. */ - emit(asm.Opcodes.ATHROW) + if (lastInsn.getOpcode != asm.Opcodes.ATHROW) + emit(asm.Opcodes.ATHROW) } else if (from.isNullType) { - bc drop from - emit(asm.Opcodes.ACONST_NULL) + /* After loading an expression of type `scala.runtime.Null$`, introduce POP; ACONST_NULL. + * This is required to pass the verifier: in Scala's type system, Null conforms to any + * reference type. In bytecode, the type Null is represented by scala.runtime.Null$, which + * is not a subtype of all reference types. Example: + * + * def nl: Null = null // in bytecode, nl has return type scala.runtime.Null$ + * val a: String = nl // OK for Scala but not for the JVM, scala.runtime.Null$ does not conform to String + * + * In order to fix the above problem, the value returned by nl is dropped and ACONST_NULL is + * inserted instead - after all, an expression of type scala.runtime.Null$ can only be null. + */ + if (lastInsn.getOpcode != asm.Opcodes.ACONST_NULL) { + bc drop from + emit(asm.Opcodes.ACONST_NULL) + } } else (from, to) match { case (BYTE, LONG) | (SHORT, LONG) | (CHAR, LONG) | (INT, LONG) => bc.emitT2T(INT, LONG) @@ -902,7 +918,7 @@ abstract class BCodeBodyBuilder extends BCodeSkelBuilder { (args zip params) filterNot isTrivial } - // first push *all* arguments. This makes sure muliple uses of the same labelDef-var will all denote the (previous) value. + // first push *all* arguments. This makes sure multiple uses of the same labelDef-var will all denote the (previous) value. aps foreach { case (arg, param) => genLoad(arg, locals(param).tk) } // `locals` is known to contain `param` because `genDefDef()` visited `labelDefsAtOrUnder` // second assign one by one to the LabelDef's variables. @@ -922,7 +938,7 @@ abstract class BCodeBodyBuilder extends BCodeSkelBuilder { def genLoadModule(tree: Tree): BType = { val module = ( if (!tree.symbol.isPackageClass) tree.symbol - else tree.symbol.info.member(nme.PACKAGE) match { + else tree.symbol.info.packageObject match { case NoSymbol => abort(s"SI-5604: Cannot use package as value: $tree") case s => abort(s"SI-5604: found package class where package object expected: $tree") } @@ -942,7 +958,7 @@ abstract class BCodeBodyBuilder extends BCodeSkelBuilder { asm.Opcodes.GETSTATIC, mbt.internalName /* + "$" */ , strMODULE_INSTANCE_FIELD, - mbt.descriptor // for nostalgics: toTypeKind(module.tpe).descriptor + mbt.descriptor // for nostalgics: typeToBType(module.tpe).descriptor ) } } @@ -978,92 +994,113 @@ abstract class BCodeBodyBuilder extends BCodeSkelBuilder { def genStringConcat(tree: Tree): BType = { lineNumber(tree) liftStringConcat(tree) match { - // Optimization for expressions of the form "" + x. We can avoid the StringBuilder. case List(Literal(Constant("")), arg) => - genLoad(arg, ObjectReference) - genCallMethod(String_valueOf, icodes.opcodes.Static(onInstance = false), arg.pos) + genLoad(arg, ObjectRef) + genCallMethod(String_valueOf, InvokeStyle.Static, arg.pos) case concatenations => bc.genStartConcat(tree.pos) for (elem <- concatenations) { - val kind = tpeTK(elem) - genLoad(elem, kind) - bc.genStringConcat(kind, elem.pos) + val loadedElem = elem match { + case Apply(boxOp, value :: Nil) if currentRun.runDefinitions.isBox(boxOp.symbol) => + // Eliminate boxing of primitive values. Boxing is introduced by erasure because + // there's only a single synthetic `+` method "added" to the string class. + value + + case _ => elem + } + val elemType = tpeTK(loadedElem) + genLoad(loadedElem, elemType) + bc.genConcat(elemType, loadedElem.pos) } bc.genEndConcat(tree.pos) - } - - StringReference + StringRef } - def genCallMethod(method: Symbol, style: InvokeStyle, pos: Position, hostClass0: Symbol = null) { - - val siteSymbol = claszSymbol - val hostSymbol = if (hostClass0 == null) method.owner else hostClass0 + /** + * Generate a method invocation. If `specificReceiver != null`, it is used as receiver in the + * invocation instruction, otherwise `method.owner`. A specific receiver class is needed to + * prevent an IllegalAccessError, (aladdin bug 455). + */ + def genCallMethod(method: Symbol, style: InvokeStyle, pos: Position, specificReceiver: Symbol = null): BType = { val methodOwner = method.owner - // info calls so that types are up to date; erasure may add lateINTERFACE to traits - hostSymbol.info ; methodOwner.info - - def needsInterfaceCall(sym: Symbol) = ( - sym.isInterface - || sym.isJavaDefined && sym.isNonBottomSubClass(definitions.ClassfileAnnotationClass) - ) - - // whether to reference the type of the receiver or - // the type of the method owner - val useMethodOwner = ( - style != icodes.opcodes.Dynamic - || hostSymbol.isBottomClass - || methodOwner == definitions.ObjectClass - ) - val receiver = if (useMethodOwner) methodOwner else hostSymbol - val jowner = internalName(receiver) - val jname = method.javaSimpleName.toString - val bmType = asmMethodType(method) - val mdescr = bmType.descriptor - - def initModule() { - // we initialize the MODULE$ field immediately after the super ctor - if (!isModuleInitialized && - jMethodName == INSTANCE_CONSTRUCTOR_NAME && - jname == INSTANCE_CONSTRUCTOR_NAME && - isStaticModuleClass(siteSymbol)) { - isModuleInitialized = true - mnode.visitVarInsn(asm.Opcodes.ALOAD, 0) - mnode.visitFieldInsn( - asm.Opcodes.PUTSTATIC, - thisName, - strMODULE_INSTANCE_FIELD, - "L" + thisName + ";" - ) + // the class used in the invocation's method descriptor in the classfile + val receiverClass = { + if (specificReceiver != null) + assert(style.isVirtual || specificReceiver == methodOwner, s"specificReceiver can only be specified for virtual calls. $method - $specificReceiver") + + val useSpecificReceiver = specificReceiver != null && !specificReceiver.isBottomClass + val receiver = if (useSpecificReceiver) specificReceiver else methodOwner + + // workaround for a JVM bug: https://bugs.openjdk.java.net/browse/JDK-8154587 + // when an interface method overrides a member of Object (note that all interfaces implicitly + // have superclass Object), the receiver needs to be the interface declaring the override (and + // not a sub-interface that inherits it). example: + // trait T { override def clone(): Object = "" } + // trait U extends T + // class C extends U + // class D { def f(u: U) = u.clone() } + // The invocation `u.clone()` needs `T` as a receiver: + // - using Object is illegal, as Object.clone is protected + // - using U results in a `NoSuchMethodError: U.clone. This is the JVM bug. + // Note that a mixin forwarder is generated, so the correct method is executed in the end: + // class C { override def clone(): Object = super[T].clone() } + val isTraitMethodOverridingObjectMember = { + receiver != methodOwner && // fast path - the boolean is used to pick either of these two, if they are the same it does not matter + style.isVirtual && + receiver.isTraitOrInterface && + ObjectTpe.decl(method.name).exists && // fast path - compute overrideChain on the next line only if necessary + method.overrideChain.last.owner == ObjectClass } + if (isTraitMethodOverridingObjectMember) methodOwner else receiver } - if (style.isStatic) { - if (style.hasInstance) { bc.invokespecial (jowner, jname, mdescr, pos) } - else { bc.invokestatic (jowner, jname, mdescr, pos) } - } - else if (style.isDynamic) { - if (needsInterfaceCall(receiver)) { bc.invokeinterface(jowner, jname, mdescr, pos) } - else { bc.invokevirtual (jowner, jname, mdescr, pos) } + receiverClass.info // ensure types the type is up to date; erasure may add lateINTERFACE to traits + val receiverBType = classBTypeFromSymbol(receiverClass) + val receiverName = receiverBType.internalName + + def needsInterfaceCall(sym: Symbol) = { + sym.isTraitOrInterface || + sym.isJavaDefined && sym.isNonBottomSubClass(definitions.ClassfileAnnotationClass) } - else { - assert(style.isSuper, s"An unknown InvokeStyle: $style") - bc.invokespecial(jowner, jname, mdescr, pos) - initModule() + + val jname = method.javaSimpleName.toString + val bmType = methodBTypeFromSymbol(method) + val mdescr = bmType.descriptor + + val isInterface = receiverBType.isInterface.get + import InvokeStyle._ + if (style == Super) { + assert(receiverClass == methodOwner, s"for super call, expecting $receiverClass == $methodOwner") + if (receiverClass.isTrait && !receiverClass.isJavaDefined) { + val staticDesc = MethodBType(typeToBType(method.owner.info) :: bmType.argumentTypes, bmType.returnType).descriptor + val staticName = traitSuperAccessorName(method).toString + bc.invokestatic(receiverName, staticName, staticDesc, isInterface, pos) + } else { + if (receiverClass.isTraitOrInterface) { + // An earlier check in Mixin reports an error in this case, so it doesn't reach the backend + assert(cnode.interfaces.contains(receiverName), s"cannot invokespecial $receiverName.$jname, the interface is not a direct parent.") + } + bc.invokespecial(receiverName, jname, mdescr, isInterface, pos) + } + } else { + val opc = style match { + case Static => Opcodes.INVOKESTATIC + case Special => Opcodes.INVOKESPECIAL + case Virtual => if (isInterface) Opcodes.INVOKEINTERFACE else Opcodes.INVOKEVIRTUAL + } + bc.emitInvoke(opc, receiverName, jname, mdescr, isInterface, pos) } + bmType.returnType } // end of genCallMethod() /* Generate the scala ## method. */ def genScalaHash(tree: Tree, applyPos: Position): BType = { - genLoadModule(ScalaRunTimeModule) // TODO why load ScalaRunTimeModule if ## has InvokeStyle of Static(false) ? - genLoad(tree, ObjectReference) - genCallMethod(hashMethodSym, icodes.opcodes.Static(onInstance = false), applyPos) - - INT + genLoad(tree, ObjectRef) + genCallMethod(hashMethodSym, InvokeStyle.Static, applyPos) } /* @@ -1082,86 +1119,98 @@ abstract class BCodeBodyBuilder extends BCodeSkelBuilder { } /* Emit code to compare the two top-most stack values using the 'op' operator. */ - private def genCJUMP(success: asm.Label, failure: asm.Label, op: TestOp, tk: BType) { - if (tk.isIntSizedType) { // BOOL, BYTE, CHAR, SHORT, or INT - bc.emitIF_ICMP(op, success) - } else if (tk.isRef) { // REFERENCE(_) | ARRAY(_) - bc.emitIF_ACMP(op, success) - } else { - (tk: @unchecked) match { - case LONG => emit(asm.Opcodes.LCMP) - case FLOAT => - if (op == icodes.LT || op == icodes.LE) emit(asm.Opcodes.FCMPG) - else emit(asm.Opcodes.FCMPL) - case DOUBLE => - if (op == icodes.LT || op == icodes.LE) emit(asm.Opcodes.DCMPG) - else emit(asm.Opcodes.DCMPL) + private def genCJUMP(success: asm.Label, failure: asm.Label, op: TestOp, tk: BType, targetIfNoJump: asm.Label, negated: Boolean = false) { + if (targetIfNoJump == success) genCJUMP(failure, success, op.negate, tk, targetIfNoJump, negated = !negated) + else { + if (tk.isIntSizedType) { // BOOL, BYTE, CHAR, SHORT, or INT + bc.emitIF_ICMP(op, success) + } else if (tk.isRef) { // REFERENCE(_) | ARRAY(_) + bc.emitIF_ACMP(op, success) + } else { + def useCmpG = if (negated) op == TestOp.GT || op == TestOp.GE else op == TestOp.LT || op == TestOp.LE + (tk: @unchecked) match { + case LONG => emit(asm.Opcodes.LCMP) + case FLOAT => emit(if (useCmpG) asm.Opcodes.FCMPG else asm.Opcodes.FCMPL) + case DOUBLE => emit(if (useCmpG) asm.Opcodes.DCMPG else asm.Opcodes.DCMPL) + } + bc.emitIF(op, success) } - bc.emitIF(op, success) + if (targetIfNoJump != failure) bc goTo failure } - bc goTo failure } /* Emits code to compare (and consume) stack-top and zero using the 'op' operator */ - private def genCZJUMP(success: asm.Label, failure: asm.Label, op: TestOp, tk: BType) { - if (tk.isIntSizedType) { // BOOL, BYTE, CHAR, SHORT, or INT - bc.emitIF(op, success) - } else if (tk.isRef) { // REFERENCE(_) | ARRAY(_) - // @unchecked because references aren't compared with GT, GE, LT, LE. - (op : @unchecked) match { - case icodes.EQ => bc emitIFNULL success - case icodes.NE => bc emitIFNONNULL success - } - } else { - (tk: @unchecked) match { - case LONG => - emit(asm.Opcodes.LCONST_0) - emit(asm.Opcodes.LCMP) - case FLOAT => - emit(asm.Opcodes.FCONST_0) - if (op == icodes.LT || op == icodes.LE) emit(asm.Opcodes.FCMPG) - else emit(asm.Opcodes.FCMPL) - case DOUBLE => - emit(asm.Opcodes.DCONST_0) - if (op == icodes.LT || op == icodes.LE) emit(asm.Opcodes.DCMPG) - else emit(asm.Opcodes.DCMPL) + private def genCZJUMP(success: asm.Label, failure: asm.Label, op: TestOp, tk: BType, targetIfNoJump: asm.Label, negated: Boolean = false) { + if (targetIfNoJump == success) genCZJUMP(failure, success, op.negate, tk, targetIfNoJump, negated = !negated) + else { + if (tk.isIntSizedType) { // BOOL, BYTE, CHAR, SHORT, or INT + bc.emitIF(op, success) + } else if (tk.isRef) { // REFERENCE(_) | ARRAY(_) + op match { // references are only compared with EQ and NE + case TestOp.EQ => bc emitIFNULL success + case TestOp.NE => bc emitIFNONNULL success + } + } else { + def useCmpG = if (negated) op == TestOp.GT || op == TestOp.GE else op == TestOp.LT || op == TestOp.LE + (tk: @unchecked) match { + case LONG => + emit(asm.Opcodes.LCONST_0) + emit(asm.Opcodes.LCMP) + case FLOAT => + emit(asm.Opcodes.FCONST_0) + emit(if (useCmpG) asm.Opcodes.FCMPG else asm.Opcodes.FCMPL) + case DOUBLE => + emit(asm.Opcodes.DCONST_0) + emit(if (useCmpG) asm.Opcodes.DCMPG else asm.Opcodes.DCMPL) + } + bc.emitIF(op, success) } - bc.emitIF(op, success) + if (targetIfNoJump != failure) bc goTo failure } - bc goTo failure } - val testOpForPrimitive: Array[TestOp] = Array( - icodes.EQ, icodes.NE, icodes.EQ, icodes.NE, icodes.LT, icodes.LE, icodes.GE, icodes.GT - ) + def testOpForPrimitive(primitiveCode: Int) = (primitiveCode: @switch) match { + case scalaPrimitives.ID => TestOp.EQ + case scalaPrimitives.NI => TestOp.NE + case scalaPrimitives.EQ => TestOp.EQ + case scalaPrimitives.NE => TestOp.NE + case scalaPrimitives.LT => TestOp.LT + case scalaPrimitives.LE => TestOp.LE + case scalaPrimitives.GT => TestOp.GT + case scalaPrimitives.GE => TestOp.GE + } + + /** Some useful equality helpers. */ + def isNull(t: Tree) = PartialFunction.cond(t) { case Literal(Constant(null)) => true } + def isLiteral(t: Tree) = PartialFunction.cond(t) { case Literal(_) => true } + def isNonNullExpr(t: Tree) = isLiteral(t) || ((t.symbol ne null) && t.symbol.isModule) + /** If l or r is constant null, returns the other ; otherwise null */ + def ifOneIsNull(l: Tree, r: Tree) = if (isNull(l)) r else if (isNull(r)) l else null /* * Generate code for conditional expressions. * The jump targets success/failure of the test are `then-target` and `else-target` resp. */ - private def genCond(tree: Tree, success: asm.Label, failure: asm.Label) { + private def genCond(tree: Tree, success: asm.Label, failure: asm.Label, targetIfNoJump: asm.Label) { def genComparisonOp(l: Tree, r: Tree, code: Int) { - val op: TestOp = testOpForPrimitive(code - scalaPrimitives.ID) - // special-case reference (in)equality test for null (null eq x, x eq null) - var nonNullSide: Tree = null - if (scalaPrimitives.isReferenceEqualityOp(code) && - { nonNullSide = ifOneIsNull(l, r); nonNullSide != null } - ) { - genLoad(nonNullSide, ObjectReference) - genCZJUMP(success, failure, op, ObjectReference) - } - else { + val op = testOpForPrimitive(code) + val nonNullSide = if (scalaPrimitives.isReferenceEqualityOp(code)) ifOneIsNull(l, r) else null + if (nonNullSide != null) { + // special-case reference (in)equality test for null (null eq x, x eq null) + genLoad(nonNullSide, ObjectRef) + genCZJUMP(success, failure, op, ObjectRef, targetIfNoJump) + } else { val tk = tpeTK(l).maxType(tpeTK(r)) genLoad(l, tk) genLoad(r, tk) - genCJUMP(success, failure, op, tk) + genCJUMP(success, failure, op, tk, targetIfNoJump) } } - def default() = { + def loadAndTestBoolean() = { genLoad(tree, BOOL) - genCZJUMP(success, failure, icodes.NE, BOOL) + genCZJUMP(success, failure, TestOp.NE, BOOL, targetIfNoJump) } lineNumber(tree) @@ -1172,37 +1221,35 @@ abstract class BCodeBodyBuilder extends BCodeSkelBuilder { // lhs and rhs of test lazy val Select(lhs, _) = fun - val rhs = if (args.isEmpty) EmptyTree else args.head; // args.isEmpty only for ZNOT + val rhs = if (args.isEmpty) EmptyTree else args.head // args.isEmpty only for ZNOT - def genZandOrZor(and: Boolean) { // TODO WRONG + def genZandOrZor(and: Boolean) { // reaching "keepGoing" indicates the rhs should be evaluated too (ie not short-circuited). val keepGoing = new asm.Label - if (and) genCond(lhs, keepGoing, failure) - else genCond(lhs, success, keepGoing) + if (and) genCond(lhs, keepGoing, failure, targetIfNoJump = keepGoing) + else genCond(lhs, success, keepGoing, targetIfNoJump = keepGoing) markProgramPoint(keepGoing) - genCond(rhs, success, failure) + genCond(rhs, success, failure, targetIfNoJump) } getPrimitive(fun.symbol) match { - case ZNOT => genCond(lhs, failure, success) + case ZNOT => genCond(lhs, failure, success, targetIfNoJump) case ZAND => genZandOrZor(and = true) case ZOR => genZandOrZor(and = false) case code => - // TODO !!!!!!!!!! isReferenceType, in the sense of TypeKind? (ie non-array, non-boxed, non-nothing, may be null) if (scalaPrimitives.isUniversalEqualityOp(code) && tpeTK(lhs).isClass) { - // `lhs` has reference type - if (code == EQ) genEqEqPrimitive(lhs, rhs, success, failure, tree.pos) - else genEqEqPrimitive(lhs, rhs, failure, success, tree.pos) - } - else if (scalaPrimitives.isComparisonOp(code)) + // rewrite `==` to null tests and `equals`. not needed for arrays (`equals` is reference equality). + if (code == EQ) genEqEqPrimitive(lhs, rhs, success, failure, targetIfNoJump, tree.pos) + else genEqEqPrimitive(lhs, rhs, failure, success, targetIfNoJump, tree.pos) + } else if (scalaPrimitives.isComparisonOp(code)) { genComparisonOp(lhs, rhs, code) - else - default + } else + loadAndTestBoolean() } - case _ => default + case _ => loadAndTestBoolean() } } // end of genCond() @@ -1214,69 +1261,75 @@ abstract class BCodeBodyBuilder extends BCodeSkelBuilder { * @param l left-hand-side of the '==' * @param r right-hand-side of the '==' */ - def genEqEqPrimitive(l: Tree, r: Tree, success: asm.Label, failure: asm.Label, pos: Position) { + def genEqEqPrimitive(l: Tree, r: Tree, success: asm.Label, failure: asm.Label, targetIfNoJump: asm.Label, pos: Position) { /* True if the equality comparison is between values that require the use of the rich equality - * comparator (scala.runtime.Comparator.equals). This is the case when either side of the + * comparator (scala.runtime.BoxesRunTime.equals). This is the case when either side of the * comparison might have a run-time type subtype of java.lang.Number or java.lang.Character. - * When it is statically known that both sides are equal and subtypes of Number of Character, - * not using the rich equality is possible (their own equals method will do ok.) + * + * When it is statically known that both sides are equal and subtypes of Number or Character, + * not using the rich equality is possible (their own equals method will do ok), except for + * java.lang.Float and java.lang.Double: their `equals` have different behavior around `NaN` + * and `-0.0`, see Javadoc (scala-dev#329). */ val mustUseAnyComparator: Boolean = { - val areSameFinals = l.tpe.isFinalType && r.tpe.isFinalType && (l.tpe =:= r.tpe) - - !areSameFinals && platform.isMaybeBoxed(l.tpe.typeSymbol) && platform.isMaybeBoxed(r.tpe.typeSymbol) + platform.isMaybeBoxed(l.tpe.typeSymbol) && platform.isMaybeBoxed(r.tpe.typeSymbol) && { + val areSameFinals = l.tpe.isFinalType && r.tpe.isFinalType && (l.tpe =:= r.tpe) && { + val sym = l.tpe.typeSymbol + sym != BoxedFloatClass && sym != BoxedDoubleClass + } + !areSameFinals + } } if (mustUseAnyComparator) { val equalsMethod: Symbol = { if (l.tpe <:< BoxedNumberClass.tpe) { if (r.tpe <:< BoxedNumberClass.tpe) platform.externalEqualsNumNum - else if (r.tpe <:< BoxedCharacterClass.tpe) platform.externalEqualsNumObject // will be externalEqualsNumChar in 2.12, SI-9030 + else if (r.tpe <:< BoxedCharacterClass.tpe) platform.externalEqualsNumChar else platform.externalEqualsNumObject } else platform.externalEquals } - genLoad(l, ObjectReference) - genLoad(r, ObjectReference) - genCallMethod(equalsMethod, icodes.opcodes.Static(onInstance = false), pos) - genCZJUMP(success, failure, icodes.NE, BOOL) - } - else { + genLoad(l, ObjectRef) + genLoad(r, ObjectRef) + genCallMethod(equalsMethod, InvokeStyle.Static, pos) + genCZJUMP(success, failure, TestOp.NE, BOOL, targetIfNoJump) + } else { if (isNull(l)) { // null == expr -> expr eq null - genLoad(r, ObjectReference) - genCZJUMP(success, failure, icodes.EQ, ObjectReference) + genLoad(r, ObjectRef) + genCZJUMP(success, failure, TestOp.EQ, ObjectRef, targetIfNoJump) } else if (isNull(r)) { // expr == null -> expr eq null - genLoad(l, ObjectReference) - genCZJUMP(success, failure, icodes.EQ, ObjectReference) + genLoad(l, ObjectRef) + genCZJUMP(success, failure, TestOp.EQ, ObjectRef, targetIfNoJump) } else if (isNonNullExpr(l)) { // SI-7852 Avoid null check if L is statically non-null. - genLoad(l, ObjectReference) - genLoad(r, ObjectReference) - genCallMethod(Object_equals, icodes.opcodes.Dynamic, pos) - genCZJUMP(success, failure, icodes.NE, BOOL) + genLoad(l, ObjectRef) + genLoad(r, ObjectRef) + genCallMethod(Object_equals, InvokeStyle.Virtual, pos) + genCZJUMP(success, failure, TestOp.NE, BOOL, targetIfNoJump) } else { // l == r -> if (l eq null) r eq null else l.equals(r) - val eqEqTempLocal = locals.makeLocal(ObjectReference, nme.EQEQ_LOCAL_VAR.toString) + val eqEqTempLocal = locals.makeLocal(ObjectRef, nme.EQEQ_LOCAL_VAR.toString) val lNull = new asm.Label val lNonNull = new asm.Label - genLoad(l, ObjectReference) - genLoad(r, ObjectReference) + genLoad(l, ObjectRef) + genLoad(r, ObjectRef) locals.store(eqEqTempLocal) - bc dup ObjectReference - genCZJUMP(lNull, lNonNull, icodes.EQ, ObjectReference) + bc dup ObjectRef + genCZJUMP(lNull, lNonNull, TestOp.EQ, ObjectRef, targetIfNoJump = lNull) markProgramPoint(lNull) - bc drop ObjectReference + bc drop ObjectRef locals.load(eqEqTempLocal) - genCZJUMP(success, failure, icodes.EQ, ObjectReference) + genCZJUMP(success, failure, TestOp.EQ, ObjectRef, targetIfNoJump = lNonNull) markProgramPoint(lNonNull) locals.load(eqEqTempLocal) - genCallMethod(Object_equals, icodes.opcodes.Dynamic, pos) - genCZJUMP(success, failure, icodes.NE, BOOL) + genCallMethod(Object_equals, InvokeStyle.Virtual, pos) + genCZJUMP(success, failure, TestOp.NE, BOOL, targetIfNoJump) } } } @@ -1285,44 +1338,37 @@ abstract class BCodeBodyBuilder extends BCodeSkelBuilder { def genSynchronized(tree: Apply, expectedType: BType): BType def genLoadTry(tree: Try): BType - def genInvokeDynamicLambda(lambdaTarget: Symbol, arity: Int, functionalInterface: Symbol) { + def genInvokeDynamicLambda(lambdaTarget: Symbol, arity: Int, functionalInterface: Symbol, sam: Symbol, isSerializable: Boolean, addScalaSerializableMarker: Boolean) { val isStaticMethod = lambdaTarget.hasFlag(Flags.STATIC) def asmType(sym: Symbol) = classBTypeFromSymbol(sym).toASMType + val isInterface = lambdaTarget.owner.isTrait val implMethodHandle = - new asm.Handle(if (lambdaTarget.hasFlag(Flags.STATIC)) asm.Opcodes.H_INVOKESTATIC else asm.Opcodes.H_INVOKEVIRTUAL, + new asm.Handle(if (lambdaTarget.hasFlag(Flags.STATIC)) asm.Opcodes.H_INVOKESTATIC else if (isInterface) asm.Opcodes.H_INVOKEINTERFACE else asm.Opcodes.H_INVOKEVIRTUAL, classBTypeFromSymbol(lambdaTarget.owner).internalName, lambdaTarget.name.toString, - asmMethodType(lambdaTarget).descriptor) + methodBTypeFromSymbol(lambdaTarget).descriptor, + /* itf = */ isInterface) val receiver = if (isStaticMethod) Nil else lambdaTarget.owner :: Nil val (capturedParams, lambdaParams) = lambdaTarget.paramss.head.splitAt(lambdaTarget.paramss.head.length - arity) - // Requires https://github.com/scala/scala-java8-compat on the runtime classpath - val invokedType = asm.Type.getMethodDescriptor(asmType(functionalInterface), (receiver ::: capturedParams).map(sym => toTypeKind(sym.info).toASMType): _*) - - val constrainedType = new MethodBType(lambdaParams.map(p => toTypeKind(p.tpe)), toTypeKind(lambdaTarget.tpe.resultType)).toASMType - val sam = functionalInterface.info.decls.find(_.isDeferred).getOrElse(functionalInterface.info.member(nme.apply)) - val samName = sam.name.toString - val samMethodType = asmMethodType(sam).toASMType - - val flags = 3 // TODO 2.12.x Replace with LambdaMetafactory.FLAG_SERIALIZABLE | LambdaMetafactory.FLAG_MARKERS - - val ScalaSerializable = classBTypeFromSymbol(definitions.SerializableClass).toASMType - bc.jmethod.visitInvokeDynamicInsn(samName, invokedType, lambdaMetaFactoryBootstrapHandle, - /* samMethodType = */ samMethodType, - /* implMethod = */ implMethodHandle, - /* instantiatedMethodType = */ constrainedType, - /* flags = */ flags.asInstanceOf[AnyRef], - /* markerInterfaceCount = */ 1.asInstanceOf[AnyRef], - /* markerInterfaces[0] = */ ScalaSerializable, - /* bridgeCount = */ 0.asInstanceOf[AnyRef] - ) - indyLambdaHosts += this.claszSymbol + val invokedType = asm.Type.getMethodDescriptor(asmType(functionalInterface), (receiver ::: capturedParams).map(sym => typeToBType(sym.info).toASMType): _*) + val constrainedType = new MethodBType(lambdaParams.map(p => typeToBType(p.tpe)), typeToBType(lambdaTarget.tpe.resultType)).toASMType + val samMethodType = methodBTypeFromSymbol(sam).toASMType + val markers = if (addScalaSerializableMarker) classBTypeFromSymbol(definitions.SerializableClass).toASMType :: Nil else Nil + visitInvokeDynamicInsnLMF(bc.jmethod, sam.name.toString, invokedType, samMethodType, implMethodHandle, constrainedType, isSerializable, markers) + if (isSerializable) + addIndyLambdaImplMethod(cnode.name, implMethodHandle :: Nil) } } - lazy val lambdaMetaFactoryBootstrapHandle = - new asm.Handle(asm.Opcodes.H_INVOKESTATIC, - definitions.LambdaMetaFactory.fullName('/'), sn.AltMetafactory.toString, - "(Ljava/lang/invoke/MethodHandles$Lookup;Ljava/lang/String;Ljava/lang/invoke/MethodType;[Ljava/lang/Object;)Ljava/lang/invoke/CallSite;") + private def visitInvokeDynamicInsnLMF(jmethod: MethodNode, samName: String, invokedType: String, samMethodType: asm.Type, + implMethodHandle: asm.Handle, instantiatedMethodType: asm.Type, + serializable: Boolean, markerInterfaces: Seq[asm.Type]) = { + import java.lang.invoke.LambdaMetafactory.{FLAG_MARKERS, FLAG_SERIALIZABLE} + def flagIf(b: Boolean, flag: Int): Int = if (b) flag else 0 + val flags = FLAG_MARKERS | flagIf(serializable, FLAG_SERIALIZABLE) + val bsmArgs = Seq(samMethodType, implMethodHandle, instantiatedMethodType, Int.box(flags), Int.box(markerInterfaces.length)) ++ markerInterfaces + jmethod.visitInvokeDynamicInsn(samName, invokedType, lambdaMetaFactoryAltMetafactoryHandle, bsmArgs: _*) + } } diff --git a/src/compiler/scala/tools/nsc/backend/jvm/BCodeHelpers.scala b/src/compiler/scala/tools/nsc/backend/jvm/BCodeHelpers.scala index 1b97681743..a74c70a684 100644 --- a/src/compiler/scala/tools/nsc/backend/jvm/BCodeHelpers.scala +++ b/src/compiler/scala/tools/nsc/backend/jvm/BCodeHelpers.scala @@ -8,10 +8,10 @@ package tools.nsc package backend.jvm import scala.tools.asm -import scala.collection.mutable import scala.tools.nsc.io.AbstractFile import GenBCode._ import BackendReporting._ +import scala.reflect.internal.Flags /* * Traits encapsulating functionality to convert Scala AST Trees into ASM ClassNodes. @@ -22,8 +22,223 @@ import BackendReporting._ */ abstract class BCodeHelpers extends BCodeIdiomatic with BytecodeWriters { import global._ + import definitions._ import bTypes._ import coreBTypes._ + import BTypes.{InternalName, InlineInfo, MethodInlineInfo} + + /** + * True for classes generated by the Scala compiler that are considered top-level in terms of + * the InnerClass / EnclosingMethod classfile attributes. See comment in BTypes. + */ + def considerAsTopLevelImplementationArtifact(classSym: Symbol) = classSym.isSpecialized + + /** + * Cache the value of delambdafy == "inline" for each run. We need to query this value many + * times, so caching makes sense. + */ + object delambdafyInline { + private var runId = -1 + private var value = false + + def apply(): Boolean = { + if (runId != global.currentRunId) { + runId = global.currentRunId + value = settings.Ydelambdafy.value == "inline" + } + value + } + } + + def needsStaticImplMethod(sym: Symbol) = sym.hasAttachment[global.mixer.NeedStaticImpl.type] + + final def traitSuperAccessorName(sym: Symbol): Name = { + val name = sym.javaSimpleName + if (sym.isMixinConstructor) name + else name.append(nme.NAME_JOIN_STRING) + } + + /** + * True if `classSym` is an anonymous class or a local class. I.e., false if `classSym` is a + * member class. This method is used to decide if we should emit an EnclosingMethod attribute. + * It is also used to decide whether the "owner" field in the InnerClass attribute should be + * null. + */ + def isAnonymousOrLocalClass(classSym: Symbol): Boolean = { + assert(classSym.isClass, s"not a class: $classSym") + val r = exitingPickler(classSym.isAnonymousClass) || !classSym.originalOwner.isClass + if (r) { + // lambda lift renames symbols and may accidentally introduce `$lambda` into a class name, making `isDelambdafyFunction` true. + // we prevent this, see `nonAnon` in LambdaLift. + // phase travel necessary: after flatten, the name includes the name of outer classes. + // if some outer name contains $lambda, a non-lambda class is considered lambda. + assert(exitingPickler(!classSym.isDelambdafyFunction), classSym.name) + } + r + } + + /** + * The next enclosing definition in the source structure. Includes anonymous function classes + * under delambdafy:inline, even though they are only generated during UnCurry. + */ + def nextEnclosing(sym: Symbol): Symbol = { + val origOwner = sym.originalOwner + // phase travel necessary: after flatten, the name includes the name of outer classes. + // if some outer name contains $anon, a non-anon class is considered anon. + if (delambdafyInline() && exitingPickler(sym.rawowner.isAnonymousFunction)) { + // SI-9105: special handling for anonymous functions under delambdafy:inline. + // + // class C { def t = () => { def f { class Z } } } + // + // class C { def t = byNameMethod { def f { class Z } } } + // + // In both examples, the method f lambda-lifted into the anonfun class. + // + // In both examples, the enclosing method of Z is f, the enclosing class is the anonfun. + // So nextEnclosing needs to return the following chain: Z - f - anonFunClassSym - ... + // + // In the first example, the initial owner of f is a TermSymbol named "$anonfun" (note: not the anonFunClassSym!) + // In the second, the initial owner of f is t (no anon fun term symbol for by-name args!). + // + // In both cases, the rawowner of class Z is the anonFunClassSym. So the check in the `if` + // above makes sure we don't jump over the anonymous function in the by-name argument case. + // + // However, we cannot directly return the rawowner: if `sym` is Z, we need to include method f + // in the result. This is done by comparing the rawowners (read: lambdalift-targets) of `sym` + // and `sym.originalOwner`: if they are the same, then the originalOwner is "in between", and + // we need to return it. + // If the rawowners are different, the symbol was not in between. In the first example, the + // originalOwner of `f` is the anonfun-term-symbol, whose rawowner is C. So the nextEnclosing + // of `f` is its rawowner, the anonFunClassSym. + // + // In delambdafy:method we don't have that problem. The f method is lambda-lifted into C, + // not into the anonymous function class. The originalOwner chain is Z - f - C. + if (sym.originalOwner.rawowner == sym.rawowner) sym.originalOwner + else sym.rawowner + } else { + origOwner + } + } + + def nextEnclosingClass(sym: Symbol): Symbol = + if (sym.isClass) sym + else nextEnclosingClass(nextEnclosing(sym)) + + def classOriginallyNestedInClass(nestedClass: Symbol, enclosingClass: Symbol) = + nextEnclosingClass(nextEnclosing(nestedClass)) == enclosingClass + + /** + * Returns the enclosing method for non-member classes. In the following example + * + * class A { + * def f = { + * class B { + * class C + * } + * } + * } + * + * the method returns Some(f) for B, but None for C, because C is a member class. For non-member + * classes that are not enclosed by a method, it returns None: + * + * class A { + * { class B } + * } + * + * In this case, for B, we return None. + * + * The EnclosingMethod attribute needs to be added to non-member classes (see doc in BTypes). + * This is a source-level property, so we need to use the originalOwner chain to reconstruct it. + */ + private def enclosingMethodForEnclosingMethodAttribute(classSym: Symbol): Option[Symbol] = { + assert(classSym.isClass, classSym) + + def doesNotExist(method: Symbol) = { + // Value classes. Member methods of value classes exist in the generated box class. However, + // nested methods lifted into a value class are moved to the companion object and don't exist + // in the value class itself. We can identify such nested methods: the initial enclosing class + // is a value class, but the current owner is some other class (the module class). + val enclCls = nextEnclosingClass(method) + exitingPickler(enclCls.isDerivedValueClass) && method.owner != enclCls + } + + def enclosingMethod(sym: Symbol): Option[Symbol] = { + if (sym.isClass || sym == NoSymbol) None + else if (sym.isMethod && !sym.isGetter) { + if (doesNotExist(sym)) None else Some(sym) + } + else enclosingMethod(nextEnclosing(sym)) + } + enclosingMethod(nextEnclosing(classSym)) + } + + /** + * The enclosing class for emitting the EnclosingMethod attribute. Since this is a source-level + * property, this method looks at the originalOwner chain. See doc in BTypes. + */ + private def enclosingClassForEnclosingMethodAttribute(classSym: Symbol): Symbol = { + assert(classSym.isClass, classSym) + val r = nextEnclosingClass(nextEnclosing(classSym)) + r + } + + final case class EnclosingMethodEntry(owner: String, name: String, methodDescriptor: String) + + /** + * Data for emitting an EnclosingMethod attribute. None if `classSym` is a member class (not + * an anonymous or local class). See doc in BTypes. + * + * The class is parameterized by two functions to obtain a bytecode class descriptor for a class + * symbol, and to obtain a method signature descriptor fro a method symbol. These function depend + * on the implementation of GenASM / GenBCode, so they need to be passed in. + */ + def enclosingMethodAttribute(classSym: Symbol, classDesc: Symbol => String, methodDesc: Symbol => String): Option[EnclosingMethodEntry] = { + // specialized classes are always top-level, see comment in BTypes + if (isAnonymousOrLocalClass(classSym) && !considerAsTopLevelImplementationArtifact(classSym)) { + val enclosingClass = enclosingClassForEnclosingMethodAttribute(classSym) + val methodOpt = enclosingMethodForEnclosingMethodAttribute(classSym) + for (m <- methodOpt) assert(m.owner == enclosingClass, s"the owner of the enclosing method ${m.locationString} should be the same as the enclosing class $enclosingClass") + Some(EnclosingMethodEntry( + classDesc(enclosingClass), + methodOpt.map(_.javaSimpleName.toString).orNull, + methodOpt.map(methodDesc).orNull)) + } else { + None + } + } + + /** + * This is basically a re-implementation of sym.isStaticOwner, but using the originalOwner chain. + * + * The problem is that we are interested in a source-level property. Various phases changed the + * symbol's properties in the meantime, mostly lambdalift modified (destructively) the owner. + * Therefore, `sym.isStatic` is not what we want. For example, in + * object T { def f { object U } } + * the owner of U is T, so UModuleClass.isStatic is true. Phase travel does not help here. + */ + def isOriginallyStaticOwner(sym: Symbol): Boolean = + sym.isPackageClass || sym.isModuleClass && isOriginallyStaticOwner(sym.originalOwner) + + /** + * This is a hack to work around SI-9111. The completer of `methodSym` may report type errors. We + * cannot change the typer context of the completer at this point and make it silent: the context + * captured when creating the completer in the namer. However, we can temporarily replace + * global.reporter (it's a var) to store errors. + */ + def completeSilentlyAndCheckErroneous(sym: Symbol): Boolean = + if (sym.hasCompleteInfo) false + else { + val originalReporter = global.reporter + val storeReporter = new reporters.StoreReporter() + global.reporter = storeReporter + try { + sym.info + } finally { + global.reporter = originalReporter + } + sym.isErroneous + } + /* * must-single-thread @@ -117,7 +332,7 @@ abstract class BCodeHelpers extends BCodeIdiomatic with BytecodeWriters { failNoForwarder("companion contains its own main method (implementation restriction: no main is allowed, regardless of signature)") else if (companion.isTrait) failNoForwarder("companion is a trait") - // Now either succeeed, or issue some additional warnings for things which look like + // Now either succeed, or issue some additional warnings for things which look like // attempts to be java main methods. else (possibles exists definitions.isJavaMainMethod) || { possibles exists { m => @@ -191,20 +406,18 @@ abstract class BCodeHelpers extends BCodeIdiomatic with BytecodeWriters { } /* - * Populates the InnerClasses JVM attribute with `refedInnerClasses`. - * In addition to inner classes mentioned somewhere in `jclass` (where `jclass` is a class file being emitted) - * `refedInnerClasses` should contain those inner classes defined as direct member classes of `jclass` - * but otherwise not mentioned in `jclass`. + * Populates the InnerClasses JVM attribute with `refedInnerClasses`. See also the doc on inner + * classes in BTypes.scala. * - * `refedInnerClasses` may contain duplicates, - * need not contain the enclosing inner classes of each inner class it lists (those are looked up for consistency). + * `refedInnerClasses` may contain duplicates, need not contain the enclosing inner classes of + * each inner class it lists (those are looked up and included). * - * This method serializes in the InnerClasses JVM attribute in an appropriate order, - * not necessarily that given by `refedInnerClasses`. + * This method serializes in the InnerClasses JVM attribute in an appropriate order, not + * necessarily that given by `refedInnerClasses`. * * can-multi-thread */ - final def addInnerClassesASM(jclass: asm.ClassVisitor, refedInnerClasses: List[ClassBType]) { + final def addInnerClasses(jclass: asm.ClassVisitor, refedInnerClasses: List[ClassBType]) { val allNestedClasses = refedInnerClasses.flatMap(_.enclosingNestedClassesChain.get).distinct // sorting ensures nested classes are listed after their enclosing class thus satisfying the Eclipse Java compiler @@ -310,85 +523,114 @@ abstract class BCodeHelpers extends BCodeIdiomatic with BytecodeWriters { final val emitLines = debugLevel >= 2 final val emitVars = debugLevel >= 3 - /* - * Contains class-symbols that: - * (a) are known to denote inner classes - * (b) are mentioned somewhere in the class being generated. - * - * In other words, the lifetime of `innerClassBufferASM` is associated to "the class being generated". - */ - final val innerClassBufferASM = mutable.Set.empty[ClassBType] - /** - * The class internal name for a given class symbol. If the symbol describes a nested class, the - * ClassBType is added to the innerClassBufferASM. + * The class internal name for a given class symbol. */ - final def internalName(sym: Symbol): String = { - // For each java class, the scala compiler creates a class and a module (thus a module class). - // If the `sym` is a java module class, we use the java class instead. This ensures that we - // register the class (instead of the module class) in innerClassBufferASM. - // The two symbols have the same name, so the resulting internalName is the same. - // Phase travel (exitingPickler) required for SI-6613 - linkedCoC is only reliable in early phases (nesting) - val classSym = if (sym.isJavaDefined && sym.isModuleClass) exitingPickler(sym.linkedClassOfClass) else sym - getClassBTypeAndRegisterInnerClass(classSym).internalName - } + final def internalName(sym: Symbol): String = classBTypeFromSymbol(sym).internalName + } // end of trait BCInnerClassGen + + trait BCAnnotGen extends BCInnerClassGen { + private lazy val AnnotationRetentionPolicyModule = AnnotationRetentionPolicyAttr.companionModule + private lazy val AnnotationRetentionPolicySourceValue = AnnotationRetentionPolicyModule.tpe.member(TermName("SOURCE")) + private lazy val AnnotationRetentionPolicyClassValue = AnnotationRetentionPolicyModule.tpe.member(TermName("CLASS")) + private lazy val AnnotationRetentionPolicyRuntimeValue = AnnotationRetentionPolicyModule.tpe.member(TermName("RUNTIME")) /** - * The ClassBType for a class symbol. If the class is nested, the ClassBType is added to the - * innerClassBufferASM. + * Annotations are not processed by the compilation pipeline like ordinary trees. Instead, the + * typer extracts them into [[AnnotationInfo]] objects which are attached to the corresponding + * symbol (sym.annotations) or type (as an AnnotatedType, eliminated by erasure). * - * TODO: clean up the way we track referenced inner classes. - * doing it during code generation is not correct when the optimizer changes the code. + * For Scala annotations this is OK: they are stored in the pickle and ignored by the backend. + * Java annotations on the other hand are additionally emitted to the classfile in Java's format. + * + * This means that [[Type]] instances within an AnnotationInfo reach the backend non-erased. Examples: + * - @(javax.annotation.Resource @annotation.meta.getter) val x = 0 + * Here, annotationInfo.atp is an AnnotatedType. + * - @SomeAnnotation[T] val x = 0 + * In principle, the annotationInfo.atp is a non-erased type ref. However, this cannot + * actually happen because Java annotations cannot be generic. + * - @javax.annotation.Resource(`type` = classOf[List[_]]) val x = 0 + * The annotationInfo.assocs contains a LiteralAnnotArg(Constant(tp)) where tp is the + * non-erased existential type. */ - final def getClassBTypeAndRegisterInnerClass(sym: Symbol): ClassBType = { - val r = classBTypeFromSymbol(sym) - if (r.isNestedClass.get) innerClassBufferASM += r - r + def erasedType(tp: Type): Type = enteringErasure { + // make sure we don't erase value class references to the type that the value class boxes + // this is basically the same logic as in erasure's preTransform, case Literal(classTag). + tp.dealiasWiden match { + case tr @ TypeRef(_, clazz, _) if clazz.isDerivedValueClass => erasure.scalaErasure.eraseNormalClassRef(tr) + case tpe => erasure.erasure(tpe.typeSymbol)(tpe) + } } - /** - * The BType for a type reference. If the result is a ClassBType for a nested class, it is added - * to the innerClassBufferASM. - * TODO: clean up the way we track referenced inner classes. - */ - final def toTypeKind(t: Type): BType = typeToBType(t) match { - case c: ClassBType if c.isNestedClass.get => - innerClassBufferASM += c - c - case r => r + def descriptorForErasedType(tp: Type): String = typeToBType(erasedType(tp)).descriptor + + /** Whether an annotation should be emitted as a Java annotation + * .initialize: if 'annot' is read from pickle, atp might be uninitialized + */ + private def shouldEmitAnnotation(annot: AnnotationInfo) = { + annot.symbol.initialize.isJavaDefined && + annot.matches(ClassfileAnnotationClass) && + retentionPolicyOf(annot) != AnnotationRetentionPolicySourceValue && + annot.args.isEmpty } - /** - * Class components that are nested classes are added to the innerClassBufferASM. - * TODO: clean up the way we track referenced inner classes. - */ - final def asmMethodType(msym: Symbol): MethodBType = { - val r = methodBTypeFromSymbol(msym) - (r.returnType :: r.argumentTypes) foreach { - case c: ClassBType if c.isNestedClass.get => innerClassBufferASM += c + private def isRuntimeVisible(annot: AnnotationInfo): Boolean = { + annot.atp.typeSymbol.getAnnotation(AnnotationRetentionAttr) match { + case Some(retentionAnnot) => + retentionAnnot.assocs.contains(nme.value -> LiteralAnnotArg(Constant(AnnotationRetentionPolicyRuntimeValue))) case _ => + // SI-8926: if the annotation class symbol doesn't have a @RetentionPolicy annotation, the + // annotation is emitted with visibility `RUNTIME` + true } - r } - /** - * The jvm descriptor of a type. If `t` references a nested class, its ClassBType is added to - * the innerClassBufferASM. - */ - final def descriptor(t: Type): String = { toTypeKind(t).descriptor } - - /** - * The jvm descriptor for a symbol. If `sym` represents a nested class, its ClassBType is added - * to the innerClassBufferASM. - */ - final def descriptor(sym: Symbol): String = { getClassBTypeAndRegisterInnerClass(sym).descriptor } - - } // end of trait BCInnerClassGen - - trait BCAnnotGen extends BCInnerClassGen { + private def retentionPolicyOf(annot: AnnotationInfo): Symbol = + annot.atp.typeSymbol.getAnnotation(AnnotationRetentionAttr).map(_.assocs).flatMap(assoc => + assoc.collectFirst { + case (`nme`.value, LiteralAnnotArg(Constant(value: Symbol))) => value + }).getOrElse(AnnotationRetentionPolicyClassValue) + + def ubytesToCharArray(bytes: Array[Byte]): Array[Char] = { + val ca = new Array[Char](bytes.length) + var idx = 0 + while(idx < bytes.length) { + val b: Byte = bytes(idx) + assert((b & ~0x7f) == 0) + ca(idx) = b.asInstanceOf[Char] + idx += 1 + } + ca + } - import genASM.{ubytesToCharArray, arrEncode} - import bCodeAsmCommon.{shouldEmitAnnotation, isRuntimeVisible} + final def arrEncode(sb: ScalaSigBytes): Array[String] = { + var strs: List[String] = Nil + val bSeven: Array[Byte] = sb.sevenBitsMayBeZero + // chop into slices of at most 65535 bytes, counting 0x00 as taking two bytes (as per JVMS 4.4.7 The CONSTANT_Utf8_info Structure) + var prevOffset = 0 + var offset = 0 + var encLength = 0 + while(offset < bSeven.length) { + val deltaEncLength = (if(bSeven(offset) == 0) 2 else 1) + val newEncLength = encLength.toLong + deltaEncLength + if(newEncLength >= 65535) { + val ba = bSeven.slice(prevOffset, offset) + strs ::= new java.lang.String(ubytesToCharArray(ba)) + encLength = 0 + prevOffset = offset + } else { + encLength += deltaEncLength + offset += 1 + } + } + if(prevOffset < offset) { + assert(offset == bSeven.length) + val ba = bSeven.slice(prevOffset, offset) + strs ::= new java.lang.String(ubytesToCharArray(ba)) + } + assert(strs.size > 1, "encode instead as one String via strEncode()") // TODO too strict? + strs.reverse.toArray + } /* * can-multi-thread @@ -420,9 +662,10 @@ abstract class BCodeHelpers extends BCodeIdiomatic with BytecodeWriters { case StringTag => assert(const.value != null, const) // TODO this invariant isn't documented in `case class Constant` av.visit(name, const.stringValue) // `stringValue` special-cases null, but that execution path isn't exercised for a const with StringTag - case ClazzTag => av.visit(name, toTypeKind(const.typeValue).toASMType) + case ClazzTag => + av.visit(name, typeToBType(erasedType(const.typeValue)).toASMType) case EnumTag => - val edesc = descriptor(const.tpe) // the class descriptor of the enumeration class. + val edesc = descriptorForErasedType(const.tpe) // the class descriptor of the enumeration class. val evalue = const.symbolValue.name.toString // value the actual enumeration value. av.visitEnum(name, edesc, evalue) } @@ -435,7 +678,7 @@ abstract class BCodeHelpers extends BCodeIdiomatic with BytecodeWriters { av.visit(name, strEncode(sb)) } else { val arrAnnotV: asm.AnnotationVisitor = av.visitArray(name) - for(arg <- genASM.arrEncode(sb)) { arrAnnotV.visit(name, arg) } + for(arg <- arrEncode(sb)) { arrAnnotV.visit(name, arg) } arrAnnotV.visitEnd() } // for the lazy val in ScalaSigBytes to be GC'ed, the invoker of emitAnnotations() should hold the ScalaSigBytes in a method-local var that doesn't escape. @@ -447,7 +690,7 @@ abstract class BCodeHelpers extends BCodeIdiomatic with BytecodeWriters { case NestedAnnotArg(annInfo) => val AnnotationInfo(typ, args, assocs) = annInfo assert(args.isEmpty, args) - val desc = descriptor(typ) // the class descriptor of the nested annotation class + val desc = descriptorForErasedType(typ) // the class descriptor of the nested annotation class val nestedVisitor = av.visitAnnotation(name, desc) emitAssocs(nestedVisitor, assocs) } @@ -472,7 +715,7 @@ abstract class BCodeHelpers extends BCodeIdiomatic with BytecodeWriters { for(annot <- annotations; if shouldEmitAnnotation(annot)) { val AnnotationInfo(typ, args, assocs) = annot assert(args.isEmpty, args) - val av = cw.visitAnnotation(descriptor(typ), isRuntimeVisible(annot)) + val av = cw.visitAnnotation(descriptorForErasedType(typ), isRuntimeVisible(annot)) emitAssocs(av, assocs) } } @@ -484,7 +727,7 @@ abstract class BCodeHelpers extends BCodeIdiomatic with BytecodeWriters { for(annot <- annotations; if shouldEmitAnnotation(annot)) { val AnnotationInfo(typ, args, assocs) = annot assert(args.isEmpty, args) - val av = mw.visitAnnotation(descriptor(typ), isRuntimeVisible(annot)) + val av = mw.visitAnnotation(descriptorForErasedType(typ), isRuntimeVisible(annot)) emitAssocs(av, assocs) } } @@ -496,7 +739,7 @@ abstract class BCodeHelpers extends BCodeIdiomatic with BytecodeWriters { for(annot <- annotations; if shouldEmitAnnotation(annot)) { val AnnotationInfo(typ, args, assocs) = annot assert(args.isEmpty, args) - val av = fw.visitAnnotation(descriptor(typ), isRuntimeVisible(annot)) + val av = fw.visitAnnotation(descriptorForErasedType(typ), isRuntimeVisible(annot)) emitAssocs(av, assocs) } } @@ -511,16 +754,40 @@ abstract class BCodeHelpers extends BCodeIdiomatic with BytecodeWriters { annot <- annots) { val AnnotationInfo(typ, args, assocs) = annot assert(args.isEmpty, args) - val pannVisitor: asm.AnnotationVisitor = jmethod.visitParameterAnnotation(idx, descriptor(typ), isRuntimeVisible(annot)) + val pannVisitor: asm.AnnotationVisitor = jmethod.visitParameterAnnotation(idx, descriptorForErasedType(typ), isRuntimeVisible(annot)) emitAssocs(pannVisitor, assocs) } } + /* + * must-single-thread + */ + def emitParamNames(jmethod: asm.MethodVisitor, params: List[Symbol]) = { + for (param <- params) { + var access = asm.Opcodes.ACC_FINAL + if (param.isArtifact) + access |= asm.Opcodes.ACC_SYNTHETIC + jmethod.visitParameter(param.name.decoded, access) + } + } } // end of trait BCAnnotGen trait BCJGenSigGen { - def getCurrentCUnit(): CompilationUnit + // @M don't generate java generics sigs for (members of) implementation + // classes, as they are monomorphic (TODO: ok?) + private def needsGenericSignature(sym: Symbol) = !( + // PP: This condition used to include sym.hasExpandedName, but this leads + // to the total loss of generic information if a private member is + // accessed from a closure: both the field and the accessor were generated + // without it. This is particularly bad because the availability of + // generic information could disappear as a consequence of a seemingly + // unrelated change. + settings.Ynogenericsig + || sym.isArtifact + || sym.isLiftedMethod + || sym.isBridge + ) /* @return * - `null` if no Java signature is to be added (`null` is what ASM expects in these cases). @@ -528,7 +795,63 @@ abstract class BCodeHelpers extends BCodeIdiomatic with BytecodeWriters { * * must-single-thread */ - def getGenericSignature(sym: Symbol, owner: Symbol): String = genASM.getGenericSignature(sym, owner, getCurrentCUnit()) + def getGenericSignature(sym: Symbol, owner: Symbol): String = { + val memberTpe = enteringErasure(owner.thisType.memberInfo(sym)) + getGenericSignature(sym, owner, memberTpe) + } + + def getGenericSignature(sym: Symbol, owner: Symbol, memberTpe: Type): String = { + if (!needsGenericSignature(sym)) { return null } + + val jsOpt: Option[String] = erasure.javaSig(sym, memberTpe) + if (jsOpt.isEmpty) { return null } + + val sig = jsOpt.get + log(sig) // This seems useful enough in the general case. + + def wrap(op: => Unit) = { + try { op; true } + catch { case _: Throwable => false } + } + + if (settings.Xverify) { + // Run the signature parser to catch bogus signatures. + val isValidSignature = wrap { + // Alternative: scala.tools.reflect.SigParser (frontend to sun.reflect.generics.parser.SignatureParser) + import scala.tools.asm.util.CheckClassAdapter + if (sym.isMethod) { CheckClassAdapter checkMethodSignature sig } // requires asm-util.jar + else if (sym.isTerm) { CheckClassAdapter checkFieldSignature sig } + else { CheckClassAdapter checkClassSignature sig } + } + + if(!isValidSignature) { + reporter.warning(sym.pos, + sm"""|compiler bug: created invalid generic signature for $sym in ${sym.owner.skipPackageObject.fullName} + |signature: $sig + |if this is reproducible, please report bug at https://issues.scala-lang.org/ + """.trim) + return null + } + } + + if ((settings.check containsName phaseName)) { + val normalizedTpe = enteringErasure(erasure.prepareSigMap(memberTpe)) + val bytecodeTpe = owner.thisType.memberInfo(sym) + if (!sym.isType && !sym.isConstructor && !(erasure.erasure(sym)(normalizedTpe) =:= bytecodeTpe)) { + reporter.warning(sym.pos, + sm"""|compiler bug: created generic signature for $sym in ${sym.owner.skipPackageObject.fullName} that does not conform to its erasure + |signature: $sig + |original type: $memberTpe + |normalized type: $normalizedTpe + |erasure type: $bytecodeTpe + |if this is reproducible, please report bug at http://issues.scala-lang.org/ + """.trim) + return null + } + } + + sig + } } // end of trait BCJGenSigGen @@ -541,11 +864,15 @@ abstract class BCodeHelpers extends BCodeIdiomatic with BytecodeWriters { * must-single-thread */ def addRemoteExceptionAnnot(isRemoteClass: Boolean, isJMethodPublic: Boolean, meth: Symbol) { - val needsAnnotation = ( - ( isRemoteClass || - isRemote(meth) && isJMethodPublic - ) && !(meth.throwsAnnotations contains definitions.RemoteExceptionClass) - ) + def hasThrowsRemoteException = meth.annotations.exists { + case ThrownException(exc) => exc.typeSymbol == definitions.RemoteExceptionClass + case _ => false + } + val needsAnnotation = { + (isRemoteClass || + isRemote(meth) && isJMethodPublic + ) && !hasThrowsRemoteException + } if (needsAnnotation) { val c = Constant(definitions.RemoteExceptionClass.tpe) val arg = Literal(c) setType c.tpe @@ -557,10 +884,23 @@ abstract class BCodeHelpers extends BCodeIdiomatic with BytecodeWriters { * * must-single-thread */ - private def addForwarder(isRemoteClass: Boolean, jclass: asm.ClassVisitor, module: Symbol, m: Symbol) { - val moduleName = internalName(module) - val methodInfo = module.thisType.memberInfo(m) - val paramJavaTypes: List[BType] = methodInfo.paramTypes map toTypeKind + private def addForwarder(isRemoteClass: Boolean, jclass: asm.ClassVisitor, moduleClass: Symbol, m: Symbol): Unit = { + def staticForwarderGenericSignature: String = { + // SI-3452 Static forwarder generation uses the same erased signature as the method if forwards to. + // By rights, it should use the signature as-seen-from the module class, and add suitable + // primitive and value-class boxing/unboxing. + // But for now, just like we did in mixin, we just avoid writing a wrong generic signature + // (one that doesn't erase to the actual signature). See run/t3452b for a test case. + val memberTpe = enteringErasure(moduleClass.thisType.memberInfo(m)) + val erasedMemberType = erasure.erasure(m)(memberTpe) + if (erasedMemberType =:= m.info) + getGenericSignature(m, moduleClass, memberTpe) + else null + } + + val moduleName = internalName(moduleClass) + val methodInfo = moduleClass.thisType.memberInfo(m) + val paramJavaTypes: List[BType] = methodInfo.paramTypes map typeToBType // val paramNames = 0 until paramJavaTypes.length map ("x_" + _) /* Forwarders must not be marked final, @@ -574,12 +914,12 @@ abstract class BCodeHelpers extends BCodeIdiomatic with BytecodeWriters { ) // TODO needed? for(ann <- m.annotations) { ann.symbol.initialize } - val jgensig = genASM.staticForwarderGenericSignature(m, module, getCurrentCUnit()) + val jgensig = staticForwarderGenericSignature addRemoteExceptionAnnot(isRemoteClass, hasPublicBitSet(flags), m) val (throws, others) = m.annotations partition (_.symbol == definitions.ThrowsClass) val thrownExceptions: List[String] = getExceptions(throws) - val jReturnType = toTypeKind(methodInfo.resultType) + val jReturnType = typeToBType(methodInfo.resultType) val mdesc = MethodBType(paramJavaTypes, jReturnType).descriptor val mirrorMethodName = m.javaSimpleName.toString val mirrorMethod: asm.MethodVisitor = jclass.visitMethod( @@ -595,7 +935,7 @@ abstract class BCodeHelpers extends BCodeIdiomatic with BytecodeWriters { mirrorMethod.visitCode() - mirrorMethod.visitFieldInsn(asm.Opcodes.GETSTATIC, moduleName, strMODULE_INSTANCE_FIELD, descriptor(module)) + mirrorMethod.visitFieldInsn(asm.Opcodes.GETSTATIC, moduleName, strMODULE_INSTANCE_FIELD, classBTypeFromSymbol(moduleClass).descriptor) var index = 0 for(jparamType <- paramJavaTypes) { @@ -604,7 +944,7 @@ abstract class BCodeHelpers extends BCodeIdiomatic with BytecodeWriters { index += jparamType.size } - mirrorMethod.visitMethodInsn(asm.Opcodes.INVOKEVIRTUAL, moduleName, mirrorMethodName, asmMethodType(m).descriptor, false) + mirrorMethod.visitMethodInsn(asm.Opcodes.INVOKEVIRTUAL, moduleName, mirrorMethodName, methodBTypeFromSymbol(m).descriptor, false) mirrorMethod.visitInsn(jReturnType.typedOpcode(asm.Opcodes.IRETURN)) mirrorMethod.visitMaxs(0, 0) // just to follow protocol, dummy arguments @@ -629,9 +969,9 @@ abstract class BCodeHelpers extends BCodeIdiomatic with BytecodeWriters { } debuglog(s"Potentially conflicting names for forwarders: $conflictingNames") - for (m <- moduleClass.info.membersBasedOnFlags(bCodeAsmCommon.ExcludedForwarderFlags, symtab.Flags.METHOD)) { + for (m <- moduleClass.info.membersBasedOnFlags(BCodeHelpers.ExcludedForwarderFlags, symtab.Flags.METHOD)) { if (m.isType || m.isDeferred || (m.owner eq definitions.ObjectClass) || m.isConstructor) - debuglog(s"No forwarder for '$m' from $jclassName to '$moduleClass'") + debuglog(s"No forwarder for '$m' from $jclassName to '$moduleClass': ${m.isType} || ${m.isDeferred} || ${m.owner eq definitions.ObjectClass} || ${m.isConstructor}") else if (conflictingNames(m.name)) log(s"No forwarder for $m due to conflict with ${linkedClass.info.member(m.name)}") else if (m.hasAccessBoundary) @@ -654,8 +994,11 @@ abstract class BCodeHelpers extends BCodeIdiomatic with BytecodeWriters { * must-single-thread */ def getExceptions(excs: List[AnnotationInfo]): List[String] = { - for (ThrownException(exc) <- excs.distinct) - yield internalName(exc) + for (ThrownException(tp) <- excs.distinct) + yield { + val erased = erasedType(tp) + internalName(erased.typeSymbol) + } } } // end of trait BCForwardersGen @@ -682,60 +1025,6 @@ abstract class BCodeHelpers extends BCodeIdiomatic with BytecodeWriters { new java.lang.Long(id) ).visitEnd() } - - /** - * Add: - * private static java.util.Map $deserializeLambdaCache$ = null - * private static Object $deserializeLambda$(SerializedLambda l) { - * var cache = $deserializeLambdaCache$ - * if (cache eq null) { - * cache = new java.util.HashMap() - * $deserializeLambdaCache$ = cache - * } - * return scala.compat.java8.runtime.LambdaDeserializer.deserializeLambda(MethodHandles.lookup(), cache, l); - * } - */ - def addLambdaDeserialize(clazz: Symbol, jclass: asm.ClassVisitor): Unit = { - val cw = jclass - import scala.tools.asm.Opcodes._ - - // Need to force creation of BTypes for these as `getCommonSuperClass` is called on - // automatically computing the max stack size (`visitMaxs`) during method writing. - javaUtilHashMapReference - javaUtilMapReference - - cw.visitInnerClass("java/lang/invoke/MethodHandles$Lookup", "java/lang/invoke/MethodHandles", "Lookup", ACC_PUBLIC + ACC_FINAL + ACC_STATIC) - - { - val fv = cw.visitField(ACC_PRIVATE + ACC_STATIC + ACC_SYNTHETIC, "$deserializeLambdaCache$", "Ljava/util/Map;", null, null) - fv.visitEnd() - } - - { - val mv = cw.visitMethod(ACC_PRIVATE + ACC_STATIC + ACC_SYNTHETIC, "$deserializeLambda$", "(Ljava/lang/invoke/SerializedLambda;)Ljava/lang/Object;", null, null) - mv.visitCode() - // javaBinaryName returns the internal name of a class. Also used in BTypesFromsymbols.classBTypeFromSymbol. - mv.visitFieldInsn(GETSTATIC, clazz.javaBinaryName.toString, "$deserializeLambdaCache$", "Ljava/util/Map;") - mv.visitVarInsn(ASTORE, 1) - mv.visitVarInsn(ALOAD, 1) - val l0 = new asm.Label() - mv.visitJumpInsn(IFNONNULL, l0) - mv.visitTypeInsn(NEW, "java/util/HashMap") - mv.visitInsn(DUP) - mv.visitMethodInsn(INVOKESPECIAL, "java/util/HashMap", "<init>", "()V", false) - mv.visitVarInsn(ASTORE, 1) - mv.visitVarInsn(ALOAD, 1) - mv.visitFieldInsn(PUTSTATIC, clazz.javaBinaryName.toString, "$deserializeLambdaCache$", "Ljava/util/Map;") - mv.visitLabel(l0) - mv.visitFieldInsn(GETSTATIC, "scala/compat/java8/runtime/LambdaDeserializer$", "MODULE$", "Lscala/compat/java8/runtime/LambdaDeserializer$;") - mv.visitMethodInsn(INVOKESTATIC, "java/lang/invoke/MethodHandles", "lookup", "()Ljava/lang/invoke/MethodHandles$Lookup;", false) - mv.visitVarInsn(ALOAD, 1) - mv.visitVarInsn(ALOAD, 0) - mv.visitMethodInsn(INVOKEVIRTUAL, "scala/compat/java8/runtime/LambdaDeserializer$", "deserializeLambda", "(Ljava/lang/invoke/MethodHandles$Lookup;Ljava/util/Map;Ljava/lang/invoke/SerializedLambda;)Ljava/lang/Object;", false) - mv.visitInsn(ARETURN) - mv.visitEnd() - } - } } // end of trait BCClassGen /* functionality for building plain and mirror classes */ @@ -748,9 +1037,6 @@ abstract class BCodeHelpers extends BCodeIdiomatic with BytecodeWriters { /* builder of mirror classes */ class JMirrorBuilder extends JCommonBuilder { - private var cunit: CompilationUnit = _ - def getCurrentCUnit(): CompilationUnit = cunit; - /* Generate a mirror class for a top-level module. A mirror class is a class * containing only static methods that forward to the corresponding method * on the MODULE instance of the given Scala object. It will only be @@ -762,8 +1048,6 @@ abstract class BCodeHelpers extends BCodeIdiomatic with BytecodeWriters { def genMirrorClass(moduleClass: Symbol, cunit: CompilationUnit): asm.tree.ClassNode = { assert(moduleClass.isModuleClass) assert(moduleClass.companionClass == NoSymbol, moduleClass) - innerClassBufferASM.clear() - this.cunit = cunit val bType = mirrorClassClassBType(moduleClass) val mirrorClass = new asm.tree.ClassNode @@ -772,7 +1056,7 @@ abstract class BCodeHelpers extends BCodeIdiomatic with BytecodeWriters { bType.info.get.flags, bType.internalName, null /* no java-generic-signature */, - ObjectReference.internalName, + ObjectRef.internalName, EMPTY_STRING_ARRAY ) @@ -785,9 +1069,6 @@ abstract class BCodeHelpers extends BCodeIdiomatic with BytecodeWriters { addForwarders(isRemote(moduleClass), mirrorClass, bType.internalName, moduleClass) - innerClassBufferASM ++= bType.info.get.nestedClasses - addInnerClassesASM(mirrorClass, innerClassBufferASM.toList) - mirrorClass.visitEnd() ("" + moduleClass.name) // this side-effect is necessary, really. @@ -811,18 +1092,15 @@ abstract class BCodeHelpers extends BCodeIdiomatic with BytecodeWriters { def javaSimpleName(s: Symbol): String = { s.javaSimpleName.toString } - innerClassBufferASM.clear() - - val flags = javaFlags(cls) + val beanInfoType = beanInfoClassClassBType(cls) - val beanInfoName = (internalName(cls) + "BeanInfo") val beanInfoClass = new asm.tree.ClassNode beanInfoClass.visit( classfileVersion, - flags, - beanInfoName, + beanInfoType.info.get.flags, + beanInfoType.internalName, null, // no java-generic-signature - "scala/beans/ScalaBeanInfo", + sbScalaBeanInfoRef.internalName, EMPTY_STRING_ARRAY ) @@ -859,7 +1137,7 @@ abstract class BCodeHelpers extends BCodeIdiomatic with BytecodeWriters { EMPTY_STRING_ARRAY // no throwable exceptions ) - val stringArrayJType: BType = ArrayBType(StringReference) + val stringArrayJType: BType = ArrayBType(StringRef) val conJType: BType = MethodBType( classBTypeFromSymbol(definitions.ClassClass) :: stringArrayJType :: stringArrayJType :: Nil, UNIT @@ -872,7 +1150,7 @@ abstract class BCodeHelpers extends BCodeIdiomatic with BytecodeWriters { constructor.visitLdcInsn(new java.lang.Integer(fi)) if (f == null) { constructor.visitInsn(asm.Opcodes.ACONST_NULL) } else { constructor.visitLdcInsn(f) } - constructor.visitInsn(StringReference.typedOpcode(asm.Opcodes.IASTORE)) + constructor.visitInsn(StringRef.typedOpcode(asm.Opcodes.IASTORE)) fi += 1 } } @@ -885,12 +1163,12 @@ abstract class BCodeHelpers extends BCodeIdiomatic with BytecodeWriters { // push the string array of field information constructor.visitLdcInsn(new java.lang.Integer(fieldList.length)) - constructor.visitTypeInsn(asm.Opcodes.ANEWARRAY, StringReference.internalName) + constructor.visitTypeInsn(asm.Opcodes.ANEWARRAY, StringRef.internalName) push(fieldList) // push the string array of method information constructor.visitLdcInsn(new java.lang.Integer(methodList.length)) - constructor.visitTypeInsn(asm.Opcodes.ANEWARRAY, StringReference.internalName) + constructor.visitTypeInsn(asm.Opcodes.ANEWARRAY, StringRef.internalName) push(methodList) // invoke the superclass constructor, which will do the @@ -901,9 +1179,6 @@ abstract class BCodeHelpers extends BCodeIdiomatic with BytecodeWriters { constructor.visitMaxs(0, 0) // just to follow protocol, dummy arguments constructor.visitEnd() - innerClassBufferASM ++= classBTypeFromSymbol(cls).info.get.nestedClasses - addInnerClassesASM(beanInfoClass, innerClassBufferASM.toList) - beanInfoClass.visitEnd() beanInfoClass @@ -932,8 +1207,7 @@ abstract class BCodeHelpers extends BCodeIdiomatic with BytecodeWriters { * must-single-thread */ def legacyAddCreatorCode(clinit: asm.MethodVisitor, cnode: asm.tree.ClassNode, thisName: String) { - // this tracks the inner class in innerClassBufferASM, if needed. - val androidCreatorType = getClassBTypeAndRegisterInnerClass(AndroidCreatorClass) + val androidCreatorType = classBTypeFromSymbol(AndroidCreatorClass) val tdesc_creator = androidCreatorType.descriptor cnode.visitField( @@ -975,3 +1249,63 @@ abstract class BCodeHelpers extends BCodeIdiomatic with BytecodeWriters { } // end of trait JAndroidBuilder } + +object BCodeHelpers { + val ExcludedForwarderFlags = { + import scala.tools.nsc.symtab.Flags._ + // Should include DEFERRED but this breaks findMember. + SPECIALIZED | LIFTED | PROTECTED | STATIC | EXPANDEDNAME | BridgeAndPrivateFlags | MACRO + } + + /** + * Valid flags for InnerClass attribute entry. + * See http://docs.oracle.com/javase/specs/jvms/se8/html/jvms-4.html#jvms-4.7.6 + */ + val INNER_CLASSES_FLAGS = { + asm.Opcodes.ACC_PUBLIC | asm.Opcodes.ACC_PRIVATE | asm.Opcodes.ACC_PROTECTED | + asm.Opcodes.ACC_STATIC | asm.Opcodes.ACC_FINAL | asm.Opcodes.ACC_INTERFACE | + asm.Opcodes.ACC_ABSTRACT | asm.Opcodes.ACC_SYNTHETIC | asm.Opcodes.ACC_ANNOTATION | + asm.Opcodes.ACC_ENUM + } + + class TestOp(val op: Int) extends AnyVal { + import TestOp._ + def negate = this match { + case EQ => NE + case NE => EQ + case LT => GE + case GE => LT + case GT => LE + case LE => GT + } + def opcodeIF = asm.Opcodes.IFEQ + op + def opcodeIFICMP = asm.Opcodes.IF_ICMPEQ + op + } + + object TestOp { + // the order here / op numbers are important to get the correct result when calling opcodeIF + val EQ = new TestOp(0) + val NE = new TestOp(1) + val LT = new TestOp(2) + val GE = new TestOp(3) + val GT = new TestOp(4) + val LE = new TestOp(5) + } + + class InvokeStyle(val style: Int) extends AnyVal { + import InvokeStyle._ + def isVirtual: Boolean = this == Virtual + def isStatic : Boolean = this == Static + def isSpecial: Boolean = this == Special + def isSuper : Boolean = this == Super + + def hasInstance = this != Static + } + + object InvokeStyle { + val Virtual = new InvokeStyle(0) // InvokeVirtual or InvokeInterface + val Static = new InvokeStyle(1) // InvokeStatic + val Special = new InvokeStyle(2) // InvokeSpecial (private methods, constructors) + val Super = new InvokeStyle(3) // InvokeSpecial (super calls) + } +} diff --git a/src/compiler/scala/tools/nsc/backend/jvm/BCodeICodeCommon.scala b/src/compiler/scala/tools/nsc/backend/jvm/BCodeICodeCommon.scala deleted file mode 100644 index 50d20921d5..0000000000 --- a/src/compiler/scala/tools/nsc/backend/jvm/BCodeICodeCommon.scala +++ /dev/null @@ -1,25 +0,0 @@ -/* NSC -- new Scala compiler - * Copyright 2005-2014 LAMP/EPFL - * @author Martin Odersky - */ - -package scala.tools.nsc.backend.jvm - -import scala.tools.nsc.Global -import PartialFunction._ - -/** - * This trait contains code shared between GenBCode and GenICode that depends on types defined in - * the compiler cake (Global). - */ -final class BCodeICodeCommon[G <: Global](val global: G) { - import global._ - - /** Some useful equality helpers. */ - def isNull(t: Tree) = cond(t) { case Literal(Constant(null)) => true } - def isLiteral(t: Tree) = cond(t) { case Literal(_) => true } - def isNonNullExpr(t: Tree) = isLiteral(t) || ((t.symbol ne null) && t.symbol.isModule) - - /** If l or r is constant null, returns the other ; otherwise null */ - def ifOneIsNull(l: Tree, r: Tree) = if (isNull(l)) r else if (isNull(r)) l else null -} diff --git a/src/compiler/scala/tools/nsc/backend/jvm/BCodeIdiomatic.scala b/src/compiler/scala/tools/nsc/backend/jvm/BCodeIdiomatic.scala index eb0da7caef..e3d45a9b3e 100644 --- a/src/compiler/scala/tools/nsc/backend/jvm/BCodeIdiomatic.scala +++ b/src/compiler/scala/tools/nsc/backend/jvm/BCodeIdiomatic.scala @@ -12,6 +12,7 @@ import scala.annotation.switch import scala.collection.mutable import GenBCode._ import scala.tools.asm.tree.MethodInsnNode +import scala.tools.nsc.backend.jvm.BCodeHelpers.TestOp /* * A high-level facade to the ASM API for bytecode generation. @@ -28,9 +29,6 @@ abstract class BCodeIdiomatic extends SubComponent { import coreBTypes._ val classfileVersion: Int = settings.target.value match { - case "jvm-1.5" => asm.Opcodes.V1_5 - case "jvm-1.6" => asm.Opcodes.V1_6 - case "jvm-1.7" => asm.Opcodes.V1_7 case "jvm-1.8" => asm.Opcodes.V1_8 } @@ -42,7 +40,7 @@ abstract class BCodeIdiomatic extends SubComponent { if (emitStackMapFrame) asm.ClassWriter.COMPUTE_FRAMES else 0 ) - val StringBuilderClassName = "scala/collection/mutable/StringBuilder" + lazy val JavaStringBuilderClassName = jlStringBuilderRef.internalName val EMPTY_STRING_ARRAY = Array.empty[String] val EMPTY_INT_ARRAY = Array.empty[Int] @@ -109,41 +107,20 @@ abstract class BCodeIdiomatic extends SubComponent { def jmethod: asm.tree.MethodNode import asm.Opcodes; - import icodes.opcodes.{ Static, Dynamic, SuperCall } final def emit(opc: Int) { jmethod.visitInsn(opc) } - /* - * can-multi-thread - */ - final def genPrimitiveArithmetic(op: icodes.ArithmeticOp, kind: BType) { - - import icodes.{ ADD, SUB, MUL, DIV, REM, NOT } - - op match { - - case ADD => add(kind) - case SUB => sub(kind) - case MUL => mul(kind) - case DIV => div(kind) - case REM => rem(kind) - - case NOT => - if (kind.isIntSizedType) { - emit(Opcodes.ICONST_M1) - emit(Opcodes.IXOR) - } else if (kind == LONG) { - jmethod.visitLdcInsn(new java.lang.Long(-1)) - jmethod.visitInsn(Opcodes.LXOR) - } else { - abort(s"Impossible to negate an $kind") - } - - case _ => - abort(s"Unknown arithmetic primitive $op") + final def genPrimitiveNot(bType: BType): Unit = { + if (bType.isIntSizedType) { + emit(Opcodes.ICONST_M1) + emit(Opcodes.IXOR) + } else if (bType == LONG) { + jmethod.visitLdcInsn(new java.lang.Long(-1)) + jmethod.visitInsn(Opcodes.LXOR) + } else { + abort(s"Impossible to negate a $bType") } - - } // end of method genPrimitiveArithmetic() + } /* * can-multi-thread @@ -207,12 +184,13 @@ abstract class BCodeIdiomatic extends SubComponent { * can-multi-thread */ final def genStartConcat(pos: Position): Unit = { - jmethod.visitTypeInsn(Opcodes.NEW, StringBuilderClassName) + jmethod.visitTypeInsn(Opcodes.NEW, JavaStringBuilderClassName) jmethod.visitInsn(Opcodes.DUP) invokespecial( - StringBuilderClassName, + JavaStringBuilderClassName, INSTANCE_CONSTRUCTOR_NAME, "()V", + itf = false, pos ) } @@ -220,22 +198,27 @@ abstract class BCodeIdiomatic extends SubComponent { /* * can-multi-thread */ - final def genStringConcat(el: BType, pos: Position): Unit = { - - val jtype = - if (el.isArray || el.isClass) ObjectReference - else el - - val bt = MethodBType(List(jtype), StringBuilderReference) - - invokevirtual(StringBuilderClassName, "append", bt.descriptor, pos) + def genConcat(elemType: BType, pos: Position): Unit = { + val paramType = elemType match { + case ct: ClassBType if ct.isSubtypeOf(StringRef).get => StringRef + case ct: ClassBType if ct.isSubtypeOf(jlStringBufferRef).get => jlStringBufferRef + case ct: ClassBType if ct.isSubtypeOf(jlCharSequenceRef).get => jlCharSequenceRef + // Don't match for `ArrayBType(CHAR)`, even though StringBuilder has such an overload: + // `"a" + Array('b')` should NOT be "ab", but "a[C@...". + case _: RefBType => ObjectRef + // jlStringBuilder does not have overloads for byte and short, but we can just use the int version + case BYTE | SHORT => INT + case pt: PrimitiveBType => pt + } + val bt = MethodBType(List(paramType), jlStringBuilderRef) + invokevirtual(JavaStringBuilderClassName, "append", bt.descriptor, pos) } /* * can-multi-thread */ final def genEndConcat(pos: Position): Unit = { - invokevirtual(StringBuilderClassName, "toString", "()Ljava/lang/String;", pos) + invokevirtual(JavaStringBuilderClassName, "toString", "()Ljava/lang/String;", pos) } /* @@ -391,41 +374,38 @@ abstract class BCodeIdiomatic extends SubComponent { final def rem(tk: BType) { emitPrimitive(JCodeMethodN.remOpcodes, tk) } // can-multi-thread // can-multi-thread - final def invokespecial(owner: String, name: String, desc: String, pos: Position) { - addInvoke(Opcodes.INVOKESPECIAL, owner, name, desc, false, pos) + final def invokespecial(owner: String, name: String, desc: String, itf: Boolean, pos: Position): Unit = { + emitInvoke(Opcodes.INVOKESPECIAL, owner, name, desc, itf, pos) } // can-multi-thread - final def invokestatic(owner: String, name: String, desc: String, pos: Position) { - addInvoke(Opcodes.INVOKESTATIC, owner, name, desc, false, pos) + final def invokestatic(owner: String, name: String, desc: String, itf: Boolean, pos: Position): Unit = { + emitInvoke(Opcodes.INVOKESTATIC, owner, name, desc, itf, pos) } // can-multi-thread - final def invokeinterface(owner: String, name: String, desc: String, pos: Position) { - addInvoke(Opcodes.INVOKEINTERFACE, owner, name, desc, true, pos) + final def invokeinterface(owner: String, name: String, desc: String, pos: Position): Unit = { + emitInvoke(Opcodes.INVOKEINTERFACE, owner, name, desc, itf = true, pos) } // can-multi-thread - final def invokevirtual(owner: String, name: String, desc: String, pos: Position) { - addInvoke(Opcodes.INVOKEVIRTUAL, owner, name, desc, false, pos) + final def invokevirtual(owner: String, name: String, desc: String, pos: Position): Unit = { + emitInvoke(Opcodes.INVOKEVIRTUAL, owner, name, desc, itf = false, pos) } - private def addInvoke(opcode: Int, owner: String, name: String, desc: String, itf: Boolean, pos: Position) = { + def emitInvoke(opcode: Int, owner: String, name: String, desc: String, itf: Boolean, pos: Position): Unit = { val node = new MethodInsnNode(opcode, owner, name, desc, itf) jmethod.instructions.add(node) - if (settings.YoptInlinerEnabled) callsitePositions(node) = pos - } - final def invokedynamic(owner: String, name: String, desc: String) { - jmethod.visitMethodInsn(Opcodes.INVOKEDYNAMIC, owner, name, desc) + if (settings.optInlinerEnabled) callsitePositions(node) = pos } // can-multi-thread final def goTo(label: asm.Label) { jmethod.visitJumpInsn(Opcodes.GOTO, label) } // can-multi-thread - final def emitIF(cond: icodes.TestOp, label: asm.Label) { jmethod.visitJumpInsn(cond.opcodeIF, label) } + final def emitIF(cond: TestOp, label: asm.Label) { jmethod.visitJumpInsn(cond.opcodeIF, label) } // can-multi-thread - final def emitIF_ICMP(cond: icodes.TestOp, label: asm.Label) { jmethod.visitJumpInsn(cond.opcodeIFICMP, label) } + final def emitIF_ICMP(cond: TestOp, label: asm.Label) { jmethod.visitJumpInsn(cond.opcodeIFICMP, label) } // can-multi-thread - final def emitIF_ACMP(cond: icodes.TestOp, label: asm.Label) { - assert((cond == icodes.EQ) || (cond == icodes.NE), cond) - val opc = (if (cond == icodes.EQ) Opcodes.IF_ACMPEQ else Opcodes.IF_ACMPNE) + final def emitIF_ACMP(cond: TestOp, label: asm.Label) { + assert((cond == TestOp.EQ) || (cond == TestOp.NE), cond) + val opc = (if (cond == TestOp.EQ) Opcodes.IF_ACMPEQ else Opcodes.IF_ACMPNE) jmethod.visitJumpInsn(opc, label) } // can-multi-thread diff --git a/src/compiler/scala/tools/nsc/backend/jvm/BCodeSkelBuilder.scala b/src/compiler/scala/tools/nsc/backend/jvm/BCodeSkelBuilder.scala index a9b6a312e9..03df1c76fa 100644 --- a/src/compiler/scala/tools/nsc/backend/jvm/BCodeSkelBuilder.scala +++ b/src/compiler/scala/tools/nsc/backend/jvm/BCodeSkelBuilder.scala @@ -8,13 +8,12 @@ package scala.tools.nsc package backend package jvm -import scala.collection.{ mutable, immutable } -import scala.tools.nsc.backend.jvm.opt.ByteCodeRepository +import scala.collection.{immutable, mutable} import scala.tools.nsc.symtab._ - import scala.tools.asm import GenBCode._ import BackendReporting._ +import scala.tools.nsc.backend.jvm.BCodeHelpers.InvokeStyle /* * @@ -26,7 +25,6 @@ abstract class BCodeSkelBuilder extends BCodeHelpers { import global._ import bTypes._ import coreBTypes._ - import bCodeAsmCommon._ /* * There's a dedicated PlainClassBuilder for each CompilationUnit, @@ -61,48 +59,39 @@ abstract class BCodeSkelBuilder extends BCodeHelpers { // current class var cnode: asm.tree.ClassNode = null - var thisName: String = null // the internal name of the class being emitted + var thisBType: ClassBType = null var claszSymbol: Symbol = null var isCZParcelable = false var isCZStaticModule = false var isCZRemote = false - protected val indyLambdaHosts = collection.mutable.Set[Symbol]() - /* ---------------- idiomatic way to ask questions to typer ---------------- */ def paramTKs(app: Apply): List[BType] = { val Apply(fun, _) = app val funSym = fun.symbol - (funSym.info.paramTypes map toTypeKind) // this tracks mentioned inner classes (in innerClassBufferASM) + funSym.info.paramTypes map typeToBType } - def symInfoTK(sym: Symbol): BType = { - toTypeKind(sym.info) // this tracks mentioned inner classes (in innerClassBufferASM) - } + def symInfoTK(sym: Symbol): BType = typeToBType(sym.info) - def tpeTK(tree: Tree): BType = { toTypeKind(tree.tpe) } + def tpeTK(tree: Tree): BType = typeToBType(tree.tpe) def log(msg: => AnyRef) { global synchronized { global.log(msg) } } - override def getCurrentCUnit(): CompilationUnit = { cunit } - /* ---------------- helper utils for generating classes and fields ---------------- */ def genPlainClass(cd: ClassDef) { assert(cnode == null, "GenBCode detected nested methods.") - innerClassBufferASM.clear() claszSymbol = cd.symbol isCZParcelable = isAndroidParcelableClass(claszSymbol) isCZStaticModule = isStaticModuleClass(claszSymbol) isCZRemote = isRemote(claszSymbol) - thisName = internalName(claszSymbol) - - val classBType = classBTypeFromSymbol(claszSymbol) + thisBType = classBTypeFromSymbol(claszSymbol) cnode = new asm.tree.ClassNode() @@ -121,30 +110,13 @@ abstract class BCodeSkelBuilder extends BCodeHelpers { addClassFields() - innerClassBufferASM ++= classBType.info.get.nestedClasses gen(cd.impl) - - val shouldAddLambdaDeserialize = ( - settings.target.value == "jvm-1.8" - && settings.Ydelambdafy.value == "method" - && indyLambdaHosts.contains(claszSymbol)) - - if (shouldAddLambdaDeserialize) - addLambdaDeserialize(claszSymbol, cnode) - - addInnerClassesASM(cnode, innerClassBufferASM.toList) - - cnode.visitAttribute(classBType.inlineInfoAttribute.get) + cnode.visitAttribute(thisBType.inlineInfoAttribute.get) if (AsmUtils.traceClassEnabled && cnode.name.contains(AsmUtils.traceClassPattern)) AsmUtils.traceClass(cnode) - if (settings.YoptAddToBytecodeRepository) { - // The inliner needs to find all classes in the code repo, also those being compiled - byteCodeRepository.add(cnode, ByteCodeRepository.CompilationUnit) - } - assert(cd.symbol == claszSymbol, "Someone messed up BCodePhase.claszSymbol during genPlainClass().") } // end of method genPlainClass() @@ -154,31 +126,27 @@ abstract class BCodeSkelBuilder extends BCodeHelpers { private def initJClass(jclass: asm.ClassVisitor) { val bType = classBTypeFromSymbol(claszSymbol) - val superClass = bType.info.get.superClass.getOrElse(ObjectReference).internalName - val interfaceNames = bType.info.get.interfaces map { - case classBType => - if (classBType.isNestedClass.get) { innerClassBufferASM += classBType } - classBType.internalName - } + val superClass = bType.info.get.superClass.getOrElse(ObjectRef).internalName + val interfaceNames = bType.info.get.interfaces.map(_.internalName) val flags = javaFlags(claszSymbol) val thisSignature = getGenericSignature(claszSymbol, claszSymbol.owner) cnode.visit(classfileVersion, flags, - thisName, thisSignature, + thisBType.internalName, thisSignature, superClass, interfaceNames.toArray) if (emitSource) { cnode.visitSource(cunit.source.toString, null /* SourceDebugExtension */) } - enclosingMethodAttribute(claszSymbol, internalName, asmMethodType(_).descriptor) match { + enclosingMethodAttribute(claszSymbol, internalName, methodBTypeFromSymbol(_).descriptor) match { case Some(EnclosingMethodEntry(className, methodName, methodDescriptor)) => cnode.visitOuterClass(className, methodName, methodDescriptor) case _ => () } - val ssa = getAnnotPickle(thisName, claszSymbol) + val ssa = getAnnotPickle(thisBType.internalName, claszSymbol) cnode.visitAttribute(if (ssa.isDefined) pickleMarkerLocal else pickleMarkerForeign) emitAnnotations(cnode, claszSymbol.annotations ++ ssa) @@ -188,18 +156,17 @@ abstract class BCodeSkelBuilder extends BCodeHelpers { } else { - val skipStaticForwarders = (claszSymbol.isInterface || settings.noForwarders) - if (!skipStaticForwarders) { + if (!settings.noForwarders) { val lmoc = claszSymbol.companionModule // add static forwarders if there are no name conflicts; see bugs #363 and #1735 if (lmoc != NoSymbol) { // it must be a top level class (name contains no $s) val isCandidateForForwarders = { - exitingPickler { !(lmoc.name.toString contains '$') && lmoc.hasModuleFlag && !lmoc.isImplClass && !lmoc.isNestedClass } + exitingPickler { !(lmoc.name.toString contains '$') && lmoc.hasModuleFlag && !lmoc.isNestedClass } } if (isCandidateForForwarders) { log(s"Adding static forwarders from '$claszSymbol' to implementations in '$lmoc'") - addForwarders(isRemote(claszSymbol), cnode, thisName, lmoc.moduleClass) + addForwarders(isRemote(claszSymbol), cnode, thisBType.internalName, lmoc.moduleClass) } } } @@ -214,10 +181,17 @@ abstract class BCodeSkelBuilder extends BCodeHelpers { * can-multi-thread */ private def addModuleInstanceField() { + // TODO confirm whether we really don't want ACC_SYNTHETIC nor ACC_DEPRECATED + // SD-194 This can't be FINAL on JVM 1.9+ because we assign it from within the + // instance constructor, not from <clinit> directly. Assignment from <clinit>, + // after the constructor has completely finished, seems like the principled + // thing to do, but it would change behaviour when "benign" cyclic references + // between modules exist. + val mods = GenBCode.PublicStatic val fv = - cnode.visitField(GenBCode.PublicStaticFinal, // TODO confirm whether we really don't want ACC_SYNTHETIC nor ACC_DEPRECATED + cnode.visitField(mods, strMODULE_INSTANCE_FIELD, - "L" + thisName + ";", + thisBType.descriptor, null, // no java-generic-signature null // no initial value ) @@ -241,11 +215,11 @@ abstract class BCodeSkelBuilder extends BCodeHelpers { /* "legacy static initialization" */ if (isCZStaticModule) { - clinit.visitTypeInsn(asm.Opcodes.NEW, thisName) + clinit.visitTypeInsn(asm.Opcodes.NEW, thisBType.internalName) clinit.visitMethodInsn(asm.Opcodes.INVOKESPECIAL, - thisName, INSTANCE_CONSTRUCTOR_NAME, "()V", false) + thisBType.internalName, INSTANCE_CONSTRUCTOR_NAME, "()V", false) } - if (isCZParcelable) { legacyAddCreatorCode(clinit, cnode, thisName) } + if (isCZParcelable) { legacyAddCreatorCode(clinit, cnode, thisBType.internalName) } clinit.visitInsn(asm.Opcodes.RETURN) clinit.visitMaxs(0, 0) // just to follow protocol, dummy arguments @@ -253,13 +227,6 @@ abstract class BCodeSkelBuilder extends BCodeHelpers { } def addClassFields() { - /* Non-method term members are fields, except for module members. Module - * members can only happen on .NET (no flatten) for inner traits. There, - * a module symbol is generated (transformInfo in mixin) which is used - * as owner for the members of the implementation class (so that the - * backend emits them as static). - * No code is needed for this module symbol. - */ for (f <- fieldSymbols(claszSymbol)) { val javagensig = getGenericSignature(f, claszSymbol) val flags = javaFieldFlags(f) @@ -288,7 +255,6 @@ abstract class BCodeSkelBuilder extends BCodeHelpers { // used by genLoadTry() and genSynchronized() var earlyReturnVar: Symbol = null var shouldEmitCleanup = false - var insideCleanupBlock = false // line numbers var lastEmittedLineNr = -1 @@ -458,9 +424,7 @@ abstract class BCodeSkelBuilder extends BCodeHelpers { var varsInScope: List[Tuple2[Symbol, asm.Label]] = null // (local-var-sym -> start-of-scope) // helpers around program-points. - def lastInsn: asm.tree.AbstractInsnNode = { - mnode.instructions.getLast - } + def lastInsn: asm.tree.AbstractInsnNode = mnode.instructions.getLast def currProgramPoint(): asm.Label = { lastInsn match { case labnode: asm.tree.LabelNode => labnode.getLabel @@ -522,7 +486,27 @@ abstract class BCodeSkelBuilder extends BCodeHelpers { case ValDef(mods, name, tpt, rhs) => () // fields are added in `genPlainClass()`, via `addClassFields()` - case dd : DefDef => genDefDef(dd) + case dd : DefDef => + val sym = dd.symbol + if (needsStaticImplMethod(sym)) { + if (sym.isMixinConstructor) { + val statified = global.gen.mkStatic(dd, sym.name, _.cloneSymbol) + genDefDef(statified) + } else { + val forwarderDefDef = { + val dd1 = global.gen.mkStatic(deriveDefDef(dd)(_ => EmptyTree), traitSuperAccessorName(sym), _.cloneSymbol.withoutAnnotations) + dd1.symbol.setFlag(Flags.ARTIFACT).resetFlag(Flags.OVERRIDE) + val selfParam :: realParams = dd1.vparamss.head.map(_.symbol) + deriveDefDef(dd1)(_ => + atPos(dd1.pos)( + Apply(Select(global.gen.mkAttributedIdent(selfParam).setType(sym.owner.typeConstructor), dd.symbol), + realParams.map(global.gen.mkAttributedIdent)).updateAttachment(UseInvokeSpecial)) + ) + } + genDefDef(forwarderDefDef) + genDefDef(dd) + } + } else genDefDef(dd) case Template(_, _, body) => body foreach gen @@ -533,7 +517,7 @@ abstract class BCodeSkelBuilder extends BCodeHelpers { /* * must-single-thread */ - def initJMethod(flags: Int, paramAnnotations: List[List[AnnotationInfo]]) { + def initJMethod(flags: Int, params: List[Symbol]) { val jgensig = getGenericSignature(methSymbol, claszSymbol) addRemoteExceptionAnnot(isCZRemote, hasPublicBitSet(flags), methSymbol) @@ -544,7 +528,7 @@ abstract class BCodeSkelBuilder extends BCodeHelpers { if (isMethSymStaticCtor) CLASS_CONSTRUCTOR_NAME else jMethodName - val mdesc = asmMethodType(methSymbol).descriptor + val mdesc = methodBTypeFromSymbol(methSymbol).descriptor mnode = cnode.visitMethod( flags, bytecodeName, @@ -553,10 +537,9 @@ abstract class BCodeSkelBuilder extends BCodeHelpers { mkArray(thrownExceptions) ).asInstanceOf[asm.tree.MethodNode] - // TODO param names: (m.params map (p => javaName(p.sym))) - + emitParamNames(mnode, params) emitAnnotations(mnode, others) - emitParamAnnotations(mnode, paramAnnotations) + emitParamAnnotations(mnode, params.map(_.annotations)) } // end of method initJMethod @@ -568,7 +551,7 @@ abstract class BCodeSkelBuilder extends BCodeHelpers { methSymbol = dd.symbol jMethodName = methSymbol.javaSimpleName.toString - returnType = asmMethodType(dd.symbol).returnType + returnType = methodBTypeFromSymbol(dd.symbol).returnType isMethSymStaticCtor = methSymbol.isStaticConstructor resetMethodBookkeeping(dd) @@ -587,16 +570,15 @@ abstract class BCodeSkelBuilder extends BCodeHelpers { } val isNative = methSymbol.hasAnnotation(definitions.NativeAttr) - val isAbstractMethod = (methSymbol.isDeferred || methSymbol.owner.isInterface) + val isAbstractMethod = rhs == EmptyTree val flags = GenBCode.mkFlags( javaFlags(methSymbol), - if (claszSymbol.isInterface) asm.Opcodes.ACC_ABSTRACT else 0, + if (isAbstractMethod) asm.Opcodes.ACC_ABSTRACT else 0, if (methSymbol.isStrictFP) asm.Opcodes.ACC_STRICT else 0, if (isNative) asm.Opcodes.ACC_NATIVE else 0 // native methods of objects are generated in mirror classes ) - // TODO needed? for(ann <- m.symbol.annotations) { ann.symbol.initialize } - initJMethod(flags, params.map(p => p.symbol.annotations)) + initJMethod(flags, params.map(_.symbol)) /* Add method-local vars for LabelDef-params. * @@ -621,13 +603,11 @@ abstract class BCodeSkelBuilder extends BCodeHelpers { genLoad(rhs, returnType) rhs match { - case Block(_, Return(_)) => () - case Return(_) => () + case Return(_) | Block(_, Return(_)) | Throw(_) | Block(_, Throw(_)) => () case EmptyTree => globalError("Concrete method has no definition: " + dd + ( if (settings.debug) "(found: " + methSymbol.owner.info.decls.toList.mkString(", ") + ")" - else "") - ) + else "")) case _ => bc emitRETURN returnType } @@ -638,7 +618,7 @@ abstract class BCodeSkelBuilder extends BCodeHelpers { if (!hasStaticBitSet) { mnode.visitLocalVariable( "this", - "L" + thisName + ";", + thisBType.descriptor, null, veryFirstProgramPoint, onePastLastProgramPoint, @@ -697,7 +677,7 @@ abstract class BCodeSkelBuilder extends BCodeHelpers { val callee = methSymbol.enclClass.primaryConstructor val jname = callee.javaSimpleName.toString val jowner = internalName(callee.owner) - val jtype = asmMethodType(callee).descriptor + val jtype = methodBTypeFromSymbol(callee).descriptor insnModB = new asm.tree.MethodInsnNode(asm.Opcodes.INVOKESPECIAL, jowner, jname, jtype, false) } @@ -706,7 +686,7 @@ abstract class BCodeSkelBuilder extends BCodeHelpers { // android creator code if (isCZParcelable) { // add a static field ("CREATOR") to this class to cache android.os.Parcelable$Creator - val andrFieldDescr = getClassBTypeAndRegisterInnerClass(AndroidCreatorClass).descriptor + val andrFieldDescr = classBTypeFromSymbol(AndroidCreatorClass).descriptor cnode.visitField( asm.Opcodes.ACC_STATIC | asm.Opcodes.ACC_FINAL, "CREATOR", @@ -718,10 +698,10 @@ abstract class BCodeSkelBuilder extends BCodeHelpers { val callee = definitions.getMember(claszSymbol.companionModule, androidFieldName) val jowner = internalName(callee.owner) val jname = callee.javaSimpleName.toString - val jtype = asmMethodType(callee).descriptor + val jtype = methodBTypeFromSymbol(callee).descriptor insnParcA = new asm.tree.MethodInsnNode(asm.Opcodes.INVOKESTATIC, jowner, jname, jtype, false) - // PUTSTATIC `thisName`.CREATOR; - insnParcB = new asm.tree.FieldInsnNode(asm.Opcodes.PUTSTATIC, thisName, "CREATOR", andrFieldDescr) + // PUTSTATIC `thisBType.internalName`.CREATOR; + insnParcB = new asm.tree.FieldInsnNode(asm.Opcodes.PUTSTATIC, thisBType.internalName, "CREATOR", andrFieldDescr) } // insert a few instructions for initialization before each return instruction diff --git a/src/compiler/scala/tools/nsc/backend/jvm/BCodeSyncAndTry.scala b/src/compiler/scala/tools/nsc/backend/jvm/BCodeSyncAndTry.scala index b94208c1a5..add2c5ffe6 100644 --- a/src/compiler/scala/tools/nsc/backend/jvm/BCodeSyncAndTry.scala +++ b/src/compiler/scala/tools/nsc/backend/jvm/BCodeSyncAndTry.scala @@ -30,17 +30,17 @@ abstract class BCodeSyncAndTry extends BCodeBodyBuilder { def genSynchronized(tree: Apply, expectedType: BType): BType = { val Apply(fun, args) = tree - val monitor = locals.makeLocal(ObjectReference, "monitor") + val monitor = locals.makeLocal(ObjectRef, "monitor") val monCleanup = new asm.Label // if the synchronized block returns a result, store it in a local variable. // Just leaving it on the stack is not valid in MSIL (stack is cleaned when leaving try-blocks). val hasResult = (expectedType != UNIT) - val monitorResult: Symbol = if (hasResult) locals.makeLocal(tpeTK(args.head), "monitorResult") else null; + val monitorResult: Symbol = if (hasResult) locals.makeLocal(tpeTK(args.head), "monitorResult") else null /* ------ (1) pushing and entering the monitor, also keeping a reference to it in a local var. ------ */ genLoadQualifier(fun) - bc dup ObjectReference + bc dup ObjectRef locals.store(monitor) emit(asm.Opcodes.MONITORENTER) @@ -73,9 +73,11 @@ abstract class BCodeSyncAndTry extends BCodeBodyBuilder { /* ------ (4) exception-handler version of monitor-exit code. * Reached upon abrupt termination of (2). * Protected by whatever protects the whole synchronized expression. + * null => "any" exception in bytecode, like we emit for finally. + * Important not to use j/l/Throwable which dooms the method to a life of interpretation! (SD-233) * ------ */ - protect(startProtected, endProtected, currProgramPoint(), ThrowableReference) + protect(startProtected, endProtected, currProgramPoint(), null) locals.load(monitor) emit(asm.Opcodes.MONITOREXIT) emit(asm.Opcodes.ATHROW) @@ -184,7 +186,7 @@ abstract class BCodeSyncAndTry extends BCodeBodyBuilder { for (CaseDef(pat, _, caseBody) <- catches) yield { pat match { case Typed(Ident(nme.WILDCARD), tpt) => NamelessEH(tpeTK(tpt).asClassBType, caseBody) - case Ident(nme.WILDCARD) => NamelessEH(ThrowableReference, caseBody) + case Ident(nme.WILDCARD) => NamelessEH(jlThrowableRef, caseBody) case Bind(_, _) => BoundEH (pat.symbol, caseBody) } } @@ -213,7 +215,7 @@ abstract class BCodeSyncAndTry extends BCodeBodyBuilder { * please notice `tmp` has type tree.tpe, while `earlyReturnVar` has the method return type. * Because those two types can be different, dedicated vars are needed. */ - val tmp = if (guardResult) locals.makeLocal(tpeTK(tree), "tmp") else null; + val tmp = if (guardResult) locals.makeLocal(tpeTK(tree), "tmp") else null /* * upon early return from the try-body or one of its EHs (but not the EH-version of the finally-clause) @@ -236,6 +238,34 @@ abstract class BCodeSyncAndTry extends BCodeBodyBuilder { val endTryBody = currProgramPoint() bc goTo postHandlers + /** + * A return within a `try` or `catch` block where a `finally` is present ("early return") + * emits a store of the result to a local, jump to a "cleanup" version of the `finally` block, + * and sets `shouldEmitCleanup = true` (see [[PlainBodyBuilder.genReturn]]). + * + * If the try-catch is nested, outer `finally` blocks need to be emitted in a cleanup version + * as well, so the `shouldEmitCleanup` variable remains `true` until the outermost `finally`. + * Nested cleanup `finally` blocks jump to the next enclosing one. For the outermost, we emit + * a read of the local variable, a return, and we set `shouldEmitCleanup = false` (see + * [[pendingCleanups]]). + * + * Now, assume we have + * + * try { return 1 } finally { + * try { println() } finally { println() } + * } + * + * Here, the outer `finally` needs a cleanup version, but the inner one does not. The method + * here makes sure that `shouldEmitCleanup` is only propagated outwards, not inwards to + * nested `finally` blocks. + */ + def withFreshCleanupScope(body: => Unit) = { + val savedShouldEmitCleanup = shouldEmitCleanup + shouldEmitCleanup = false + body + shouldEmitCleanup = savedShouldEmitCleanup || shouldEmitCleanup + } + /* ------ (2) One EH for each case-clause (this does not include the EH-version of the finally-clause) * An EH in (2) is reached upon abrupt termination of (1). * An EH in (2) is protected by: @@ -244,8 +274,7 @@ abstract class BCodeSyncAndTry extends BCodeBodyBuilder { * ------ */ - for (ch <- caseHandlers) { - + for (ch <- caseHandlers) withFreshCleanupScope { // (2.a) emit case clause proper val startHandler = currProgramPoint() var endHandler: asm.Label = null @@ -275,9 +304,13 @@ abstract class BCodeSyncAndTry extends BCodeBodyBuilder { protect(startTryBody, endTryBody, startHandler, excType) // (2.c) emit jump to the program point where the finally-clause-for-normal-exit starts, or in effect `after` if no finally-clause was given. bc goTo postHandlers - } + // Need to save the state of `shouldEmitCleanup` at this point: while emitting the first + // version of the `finally` block below, the variable may become true. But this does not mean + // that we need a cleanup version for the current block, only for the enclosing ones. + val currentFinallyBlockNeedsCleanup = shouldEmitCleanup + /* ------ (3.A) The exception-handler-version of the finally-clause. * Reached upon abrupt termination of (1) or one of the EHs in (2). * Protected only by whatever protects the whole try-catch-finally expression. @@ -286,11 +319,11 @@ abstract class BCodeSyncAndTry extends BCodeBodyBuilder { // a note on terminology: this is not "postHandlers", despite appearances. // "postHandlers" as in the source-code view. And from that perspective, both (3.A) and (3.B) are invisible implementation artifacts. - if (hasFinally) { + if (hasFinally) withFreshCleanupScope { nopIfNeeded(startTryBody) val finalHandler = currProgramPoint() // version of the finally-clause reached via unhandled exception. protect(startTryBody, finalHandler, finalHandler, null) - val Local(eTK, _, eIdx, _) = locals(locals.makeLocal(ThrowableReference, "exc")) + val Local(eTK, _, eIdx, _) = locals(locals.makeLocal(jlThrowableRef, "exc")) bc.store(eIdx, eTK) emitFinalizer(finalizer, null, isDuplicate = true) bc.load(eIdx, eTK) @@ -314,14 +347,11 @@ abstract class BCodeSyncAndTry extends BCodeBodyBuilder { // this is not "postHandlers" either. // `shouldEmitCleanup` can be set, and at the same time this try expression may lack a finally-clause. // In other words, all combinations of (hasFinally, shouldEmitCleanup) are valid. - if (hasFinally && shouldEmitCleanup) { - val savedInsideCleanup = insideCleanupBlock - insideCleanupBlock = true + if (hasFinally && currentFinallyBlockNeedsCleanup) { markProgramPoint(finCleanup) // regarding return value, the protocol is: in place of a `return-stmt`, a sequence of `adapt, store, jump` are inserted. emitFinalizer(finalizer, null, isDuplicate = true) pendingCleanups() - insideCleanupBlock = savedInsideCleanup } /* ------ (4) finally-clause-for-normal-nonEarlyReturn-exit diff --git a/src/compiler/scala/tools/nsc/backend/jvm/BTypes.scala b/src/compiler/scala/tools/nsc/backend/jvm/BTypes.scala index 0c26e01322..3e3229d2c3 100644 --- a/src/compiler/scala/tools/nsc/backend/jvm/BTypes.scala +++ b/src/compiler/scala/tools/nsc/backend/jvm/BTypes.scala @@ -7,15 +7,18 @@ package scala.tools.nsc package backend.jvm import scala.annotation.switch +import scala.collection.{concurrent, mutable} import scala.collection.concurrent.TrieMap import scala.reflect.internal.util.Position import scala.tools.asm import asm.Opcodes -import scala.tools.asm.tree.{MethodNode, MethodInsnNode, InnerClassNode, ClassNode} +import scala.tools.asm.tree._ import scala.tools.nsc.backend.jvm.BTypes.{InlineInfo, MethodInlineInfo} import scala.tools.nsc.backend.jvm.BackendReporting._ +import scala.tools.nsc.backend.jvm.analysis.BackendUtils import scala.tools.nsc.backend.jvm.opt._ -import scala.collection.convert.decorateAsScala._ +import scala.collection.JavaConverters._ +import scala.collection.mutable.ListBuffer import scala.tools.nsc.settings.ScalaSettings /** @@ -29,6 +32,8 @@ import scala.tools.nsc.settings.ScalaSettings abstract class BTypes { import BTypes.InternalName + val backendUtils: BackendUtils[this.type] + // Some core BTypes are required here, in class BType, where no Global instance is available. // The Global is only available in the subclass BTypesFromSymbols. We cannot depend on the actual // implementation (CoreBTypesProxy) here because it has members that refer to global.Symbol. @@ -38,12 +43,14 @@ abstract class BTypes { /** * Tools for parsing classfiles, used by the inliner. */ - val byteCodeRepository: ByteCodeRepository + val byteCodeRepository: ByteCodeRepository[this.type] val localOpt: LocalOpt[this.type] val inliner: Inliner[this.type] + val inlinerHeuristics: InlinerHeuristics[this.type] + val closureOptimizer: ClosureOptimizer[this.type] val callGraph: CallGraph[this.type] @@ -56,7 +63,6 @@ abstract class BTypes { // Allows access to the compiler settings for backend components that don't have a global in scope def compilerSettings: ScalaSettings - /** * A map from internal names to ClassBTypes. Every ClassBType is added to this map on its * construction. @@ -68,19 +74,27 @@ abstract class BTypes { * Concurrent because stack map frames are computed when in the class writer, which might run * on multiple classes concurrently. */ - val classBTypeFromInternalName: collection.concurrent.Map[InternalName, ClassBType] = recordPerRunCache(TrieMap.empty) + val classBTypeFromInternalName: concurrent.Map[InternalName, ClassBType] = recordPerRunCache(TrieMap.empty) /** * Store the position of every MethodInsnNode during code generation. This allows each callsite * in the call graph to remember its source position, which is required for inliner warnings. */ - val callsitePositions: collection.concurrent.Map[MethodInsnNode, Position] = recordPerRunCache(TrieMap.empty) + val callsitePositions: concurrent.Map[MethodInsnNode, Position] = recordPerRunCache(TrieMap.empty) + + /** + * Stores callsite instructions of invocations annotated `f(): @inline/noinline`. + * Instructions are added during code generation (BCodeBodyBuilder). The maps are then queried + * when building the CallGraph, every Callsite object has an annotated(No)Inline field. + */ + val inlineAnnotatedCallsites: mutable.Set[MethodInsnNode] = recordPerRunCache(mutable.Set.empty) + val noInlineAnnotatedCallsites: mutable.Set[MethodInsnNode] = recordPerRunCache(mutable.Set.empty) /** * Contains the internal names of all classes that are defined in Java source files of the current * compilation run (mixed compilation). Used for more detailed error reporting. */ - val javaDefinedClasses: collection.mutable.Set[InternalName] = recordPerRunCache(collection.mutable.Set.empty) + val javaDefinedClasses: mutable.Set[InternalName] = recordPerRunCache(mutable.Set.empty) /** * Cache, contains methods whose unreachable instructions are eliminated. @@ -92,12 +106,47 @@ abstract class BTypes { * This cache allows running dead code elimination whenever an analyzer is used. If the method * is already optimized, DCE can return early. */ - val unreachableCodeEliminated: collection.mutable.Set[MethodNode] = recordPerRunCache(collection.mutable.Set.empty) + val unreachableCodeEliminated: mutable.Set[MethodNode] = recordPerRunCache(mutable.Set.empty) + + /** + * Cache of methods which have correct `maxLocals` / `maxStack` values assigned. This allows + * invoking `computeMaxLocalsMaxStack` whenever running an analyzer but performing the actual + * computation only when necessary. + */ + val maxLocalsMaxStackComputed: mutable.Set[MethodNode] = recordPerRunCache(mutable.Set.empty) + + /** + * Classes with indyLambda closure instantiations where the SAM type is serializable (e.g. Scala's + * FunctionN) need a `$deserializeLambda$` method. This map contains classes for which such a + * method has been generated. It is used during ordinary code generation, as well as during + * inlining: when inlining an indyLambda instruction into a class, we need to make sure the class + * has the method. + */ + val indyLambdaImplMethods: mutable.AnyRefMap[InternalName, mutable.LinkedHashSet[asm.Handle]] = recordPerRunCache(mutable.AnyRefMap()) + def addIndyLambdaImplMethod(hostClass: InternalName, handle: Seq[asm.Handle]): Seq[asm.Handle] = { + if (handle.isEmpty) Nil else { + val set = indyLambdaImplMethods.getOrElseUpdate(hostClass, mutable.LinkedHashSet()) + val added = handle.filterNot(set) + set ++= handle + added + } + } + def removeIndyLambdaImplMethod(hostClass: InternalName, handle: Seq[asm.Handle]): Unit = { + if (handle.nonEmpty) + indyLambdaImplMethods.getOrElseUpdate(hostClass, mutable.LinkedHashSet()) --= handle + } + + def getIndyLambdaImplMethods(hostClass: InternalName): Iterable[asm.Handle] = { + indyLambdaImplMethods.getOrNull(hostClass) match { + case null => Nil + case xs => xs + } + } /** * Obtain the BType for a type descriptor or internal name. For class descriptors, the ClassBType * is constructed by parsing the corresponding classfile. - * + * * Some JVM operations use either a full descriptor or only an internal name. Example: * ANEWARRAY java/lang/String // a new array of strings (internal name for the String class) * ANEWARRAY [Ljava/lang/String; // a new array of array of string (full descriptor for the String class) @@ -128,7 +177,7 @@ abstract class BTypes { val res = ClassBType(internalName) byteCodeRepository.classNode(internalName) match { case Left(msg) => res.info = Left(NoClassBTypeInfoMissingBytecode(msg)); res - case Right(c) => setClassInfoFromParsedClassfile(c, res) + case Right(c) => setClassInfoFromClassNode(c, res) } }) } @@ -138,21 +187,19 @@ abstract class BTypes { */ def classBTypeFromClassNode(classNode: ClassNode): ClassBType = { classBTypeFromInternalName.getOrElse(classNode.name, { - setClassInfoFromParsedClassfile(classNode, ClassBType(classNode.name)) + setClassInfoFromClassNode(classNode, ClassBType(classNode.name)) }) } - private def setClassInfoFromParsedClassfile(classNode: ClassNode, classBType: ClassBType): ClassBType = { + private def setClassInfoFromClassNode(classNode: ClassNode, classBType: ClassBType): ClassBType = { val superClass = classNode.superName match { case null => - assert(classNode.name == ObjectReference.internalName, s"class with missing super type: ${classNode.name}") + assert(classNode.name == ObjectRef.internalName, s"class with missing super type: ${classNode.name}") None case superName => Some(classBTypeFromParsedClassfile(superName)) } - val interfaces: List[ClassBType] = classNode.interfaces.asScala.map(classBTypeFromParsedClassfile)(collection.breakOut) - val flags = classNode.access /** @@ -197,6 +244,8 @@ abstract class BTypes { val inlineInfo = inlineInfoFromClassfile(classNode) + val interfaces: List[ClassBType] = classNode.interfaces.asScala.map(classBTypeFromParsedClassfile)(collection.breakOut) + classBType.info = Right(ClassInfo(superClass, interfaces, flags, nestedClasses, nestedInfo, inlineInfo)) classBType } @@ -226,22 +275,21 @@ abstract class BTypes { val methodInfos = classNode.methods.asScala.map(methodNode => { val info = MethodInlineInfo( effectivelyFinal = BytecodeUtils.isFinalMethod(methodNode), - traitMethodWithStaticImplementation = false, annotatedInline = false, annotatedNoInline = false) (methodNode.name + methodNode.desc, info) }).toMap InlineInfo( - traitImplClassSelfType = None, isEffectivelyFinal = BytecodeUtils.isFinalClass(classNode), + sam = inlinerHeuristics.javaSam(classNode.name), methodInfos = methodInfos, warning) } // The InlineInfo is built from the classfile (not from the symbol) for all classes that are NOT - // being compiled. For those classes, the info is only needed if the inliner is enabled, othewise + // being compiled. For those classes, the info is only needed if the inliner is enabled, otherwise // we can save the memory. - if (!compilerSettings.YoptInlinerEnabled) BTypes.EmptyInlineInfo + if (!compilerSettings.optInlinerEnabled) BTypes.EmptyInlineInfo else fromClassfileAttribute getOrElse fromClassfileWithoutAttribute } @@ -291,8 +339,8 @@ abstract class BTypes { final def isNonVoidPrimitiveType = isPrimitive && this != UNIT - final def isNullType = this == RT_NULL - final def isNothingType = this == RT_NOTHING + final def isNullType = this == srNullRef + final def isNothingType = this == srNothingRef final def isBoxed = this.isClass && boxedClasses(this.asClassBType) @@ -315,7 +363,7 @@ abstract class BTypes { this match { case ArrayBType(component) => - if (other == ObjectReference || other == jlCloneableReference || other == jioSerializableReference) true + if (other == ObjectRef || other == jlCloneableRef || other == jiSerializableRef) true else other match { case ArrayBType(otherComponent) => component.conformsTo(otherComponent).orThrow case _ => false @@ -324,7 +372,7 @@ abstract class BTypes { case classType: ClassBType => if (isBoxed) { if (other.isBoxed) this == other - else if (other == ObjectReference) true + else if (other == ObjectRef) true else other match { case otherClassType: ClassBType => classType.isSubtypeOf(otherClassType).orThrow // e.g., java/lang/Double conforms to java/lang/Number case _ => false @@ -367,7 +415,7 @@ abstract class BTypes { assert(other.isRef, s"Cannot compute maxType: $this, $other") // Approximate `lub`. The common type of two references is always ObjectReference. - ObjectReference + ObjectRef case _: MethodBType => assertionError(s"unexpected method type when computing maxType: $this") @@ -554,6 +602,8 @@ abstract class BTypes { * Terminology * ----------- * + * Diagram here: https://blogs.oracle.com/darcy/entry/nested_inner_member_and_top + * * - Nested class (JLS 8): class whose declaration occurs within the body of another class * * - Top-level class (JLS 8): non-nested class @@ -603,7 +653,7 @@ abstract class BTypes { * Fields in the InnerClass entries: * - inner class: the (nested) class C we are talking about * - outer class: the class of which C is a member. Has to be null for non-members, i.e. for - * local and anonymous classes. NOTE: this co-incides with the presence of an + * local and anonymous classes. NOTE: this coincides with the presence of an * EnclosingMethod attribute (see below) * - inner name: A string with the simple name of the inner class. Null for anonymous classes. * - flags: access property flags, details in JVMS, table in 4.7.6. Static flag: see @@ -652,7 +702,7 @@ abstract class BTypes { * local and anonymous classes, no matter if there is an enclosing method or not. Accordingly, the * "class" field (see below) must be always defined, while the "method" field may be null. * - * NOTE: When an EnclosingMethod attribute is requried (local and anonymous classes), the "outer" + * NOTE: When an EnclosingMethod attribute is required (local and anonymous classes), the "outer" * field in the InnerClass table must be null. * * Fields: @@ -760,26 +810,17 @@ abstract class BTypes { * } * * - * Traits Members - * -------------- - * - * Some trait methods don't exist in the generated interface, but only in the implementation class - * (private methods in traits for example). Since EnclosingMethod expresses a source-level property, - * but the source-level enclosing method doesn't exist in the classfile, we the enclosing method - * is null (the enclosing class is still emitted). - * See BCodeAsmCommon.considerAsTopLevelImplementationArtifact - * + * Specialized Classes, Delambdafy:method closure classes + * ------------------------------------------------------ * - * Implementation Classes, Specialized Classes, Delambdafy:method closure classes - * ------------------------------------------------------------------------------ - * - * Trait implementation classes and specialized classes are always considered top-level. Again, - * the InnerClass / EnclosingMethod attributes describe a source-level properties. The impl - * classes are compilation artifacts. + * Specialized classes are always considered top-level, as the InnerClass / EnclosingMethod + * attributes describe a source-level properties. * * The same is true for delambdafy:method closure classes. These classes are generated at * top-level in the delambdafy phase, no special support is required in the backend. * + * See also BCodeHelpers.considerAsTopLevelImplementationArtifact. + * * * Mirror Classes * -------------- @@ -837,7 +878,7 @@ abstract class BTypes { // best-effort verification. also we don't report an error if the info is a Left. def ifInit(c: ClassBType)(p: ClassBType => Boolean): Boolean = c._info == null || c.info.isLeft || p(c) - def isJLO(t: ClassBType) = t.internalName == ObjectReference.internalName + def isJLO(t: ClassBType) = t.internalName == ObjectRef.internalName assert(!ClassBType.isInternalPhantomType(internalName), s"Cannot create ClassBType for phantom type $this") @@ -900,7 +941,7 @@ abstract class BTypes { // the static flag in the InnerClass table has a special meaning, see InnerClass comment i.flags & ~Opcodes.ACC_STATIC, if (isStaticNestedClass) Opcodes.ACC_STATIC else 0 - ) & BCodeAsmCommon.INNER_CLASSES_FLAGS + ) & BCodeHelpers.INNER_CLASSES_FLAGS ) }) @@ -917,7 +958,7 @@ abstract class BTypes { def isSubtypeOf(other: ClassBType): Either[NoClassBTypeInfo, Boolean] = try { if (this == other) return Right(true) if (isInterface.orThrow) { - if (other == ObjectReference) return Right(true) // interfaces conform to Object + if (other == ObjectRef) return Right(true) // interfaces conform to Object if (!other.isInterface.orThrow) return Right(false) // this is an interface, the other is some class other than object. interfaces cannot extend classes, so the result is false. // else: this and other are both interfaces. continue to (*) } else { @@ -950,13 +991,13 @@ abstract class BTypes { // exercised by test/files/run/t4761.scala if (other.isSubtypeOf(this).orThrow) this else if (this.isSubtypeOf(other).orThrow) other - else ObjectReference + else ObjectRef case (true, false) => - if (other.isSubtypeOf(this).orThrow) this else ObjectReference + if (other.isSubtypeOf(this).orThrow) this else ObjectRef case (false, true) => - if (this.isSubtypeOf(other).orThrow) other else ObjectReference + if (this.isSubtypeOf(other).orThrow) other else ObjectRef case _ => // TODO @lry I don't really understand the reasoning here. @@ -1081,7 +1122,7 @@ abstract class BTypes { */ /** - * Just a named pair, used in CoreBTypes.asmBoxTo/asmUnboxTo. + * Just a named pair, used in CoreBTypes.srBoxesRuntimeBoxToMethods/srBoxesRuntimeUnboxToMethods. */ final case class MethodNameAndType(name: String, methodType: MethodBType) @@ -1103,24 +1144,14 @@ object BTypes { /** * Metadata about a ClassBType, used by the inliner. * - * More information may be added in the future to enable more elaborate inlinine heuristics. - * - * @param traitImplClassSelfType `Some(tp)` if this InlineInfo describes a trait, and the `self` - * parameter type of the methods in the implementation class is not - * the trait itself. Example: - * trait T { self: U => def f = 1 } - * Generates something like: - * class T$class { static def f(self: U) = 1 } - * - * In order to inline a trat method call, the INVOKEINTERFACE is - * rewritten to an INVOKESTATIC of the impl class, so we need the - * self type (U) to get the right signature. - * - * `None` if the self type is the interface type, or if this - * InlineInfo does not describe a trait. + * More information may be added in the future to enable more elaborate inline heuristics. + * Note that this class should contain information that can only be obtained from the ClassSymbol. + * Information that can be computed from the ClassNode should be added to the call graph instead. * * @param isEffectivelyFinal True if the class cannot have subclasses: final classes, module - * classes, trait impl classes. + * classes. + * + * @param sam If this class is a SAM type, the SAM's "$name$descriptor". * * @param methodInfos The [[MethodInlineInfo]]s for the methods declared in this class. * The map is indexed by the string s"$name$descriptor" (to @@ -1130,29 +1161,28 @@ object BTypes { * InlineInfo, for example if some classfile could not be found on * the classpath. This warning can be reported later by the inliner. */ - final case class InlineInfo(traitImplClassSelfType: Option[InternalName], - isEffectivelyFinal: Boolean, + final case class InlineInfo(isEffectivelyFinal: Boolean, + sam: Option[String], methodInfos: Map[String, MethodInlineInfo], warning: Option[ClassInlineInfoWarning]) - val EmptyInlineInfo = InlineInfo(None, false, Map.empty, None) + val EmptyInlineInfo = InlineInfo(false, None, Map.empty, None) /** * Metadata about a method, used by the inliner. * * @param effectivelyFinal True if the method cannot be overridden (in Scala) - * @param traitMethodWithStaticImplementation True if the method is an interface method method of - * a trait method and has a static counterpart in the - * implementation class. * @param annotatedInline True if the method is annotated `@inline` * @param annotatedNoInline True if the method is annotated `@noinline` */ final case class MethodInlineInfo(effectivelyFinal: Boolean, - traitMethodWithStaticImplementation: Boolean, annotatedInline: Boolean, annotatedNoInline: Boolean) // no static way (without symbol table instance) to get to nme.ScalaATTR / ScalaSignatureATTR val ScalaAttributeName = "Scala" val ScalaSigAttributeName = "ScalaSig" -}
\ No newline at end of file + + // when inlining, local variable names of the callee are prefixed with the name of the callee method + val InlinedLocalVariablePrefixMaxLenght = 128 +} diff --git a/src/compiler/scala/tools/nsc/backend/jvm/BTypesFromSymbols.scala b/src/compiler/scala/tools/nsc/backend/jvm/BTypesFromSymbols.scala index 45d9cc3ff3..f7ee36c1ba 100644 --- a/src/compiler/scala/tools/nsc/backend/jvm/BTypesFromSymbols.scala +++ b/src/compiler/scala/tools/nsc/backend/jvm/BTypesFromSymbols.scala @@ -7,10 +7,12 @@ package scala.tools.nsc package backend.jvm import scala.tools.asm +import scala.tools.nsc.backend.jvm.analysis.BackendUtils import scala.tools.nsc.backend.jvm.opt._ -import scala.tools.nsc.backend.jvm.BTypes.{InlineInfo, MethodInlineInfo, InternalName} +import scala.tools.nsc.backend.jvm.BTypes._ import BackendReporting._ import scala.tools.nsc.settings.ScalaSettings +import scala.reflect.internal.Flags.{DEFERRED, SYNTHESIZE_IMPL_IN_SUBCLASS} /** * This class mainly contains the method classBTypeFromSymbol, which extracts the necessary @@ -27,21 +29,22 @@ import scala.tools.nsc.settings.ScalaSettings class BTypesFromSymbols[G <: Global](val global: G) extends BTypes { import global._ import definitions._ + import genBCode._ - val bCodeICodeCommon: BCodeICodeCommon[global.type] = new BCodeICodeCommon(global) - val bCodeAsmCommon: BCodeAsmCommon[global.type] = new BCodeAsmCommon(global) - import bCodeAsmCommon._ + val backendUtils: BackendUtils[this.type] = new BackendUtils(this) // Why the proxy, see documentation of class [[CoreBTypes]]. val coreBTypes = new CoreBTypesProxy[this.type](this) import coreBTypes._ - val byteCodeRepository = new ByteCodeRepository(global.classPath, javaDefinedClasses, recordPerRunCache(collection.concurrent.TrieMap.empty)) + val byteCodeRepository: ByteCodeRepository[this.type] = new ByteCodeRepository(global.optimizerClassPath(global.classPath), this) val localOpt: LocalOpt[this.type] = new LocalOpt(this) val inliner: Inliner[this.type] = new Inliner(this) + val inlinerHeuristics: InlinerHeuristics[this.type] = new InlinerHeuristics(this) + val closureOptimizer: ClosureOptimizer[this.type] = new ClosureOptimizer(this) val callGraph: CallGraph[this.type] = new CallGraph(this) @@ -94,21 +97,24 @@ class BTypesFromSymbols[G <: Global](val global: G) extends BTypes { * scala.Null is mapped to scala.runtime.Null$. This is because there exist no class files * for the Nothing / Null. If used for example as a parameter type, we use the runtime classes * in the classfile method signature. - * - * Note that the referenced class symbol may be an implementation class. For example when - * compiling a mixed-in method that forwards to the static method in the implementation class, - * the class descriptor of the receiver (the implementation class) is obtained by creating the - * ClassBType. */ - final def classBTypeFromSymbol(classSym: Symbol): ClassBType = { + final def classBTypeFromSymbol(sym: Symbol): ClassBType = { + // For each java class, the scala compiler creates a class and a module (thus a module class). + // If the `sym` is a java module class, we use the java class instead. This ensures that the + // ClassBType is created from the main class (instead of the module class). + // The two symbols have the same name, so the resulting internalName is the same. + // Phase travel (exitingPickler) required for SI-6613 - linkedCoC is only reliable in early phases (nesting) + val classSym = if (sym.isJavaDefined && sym.isModuleClass) exitingPickler(sym.linkedClassOfClass) else sym + assert(classSym != NoSymbol, "Cannot create ClassBType from NoSymbol") assert(classSym.isClass, s"Cannot create ClassBType from non-class symbol $classSym") assertClassNotArrayNotPrimitive(classSym) - assert(!primitiveTypeMap.contains(classSym) || isCompilingPrimitive, s"Cannot create ClassBType for primitive class symbol $classSym") - if (classSym == NothingClass) RT_NOTHING - else if (classSym == NullClass) RT_NULL + assert(!primitiveTypeToBType.contains(classSym) || isCompilingPrimitive, s"Cannot create ClassBType for primitive class symbol $classSym") + + if (classSym == NothingClass) srNothingRef + else if (classSym == NullClass) srNullRef else { - val internalName = classSym.javaBinaryName.toString + val internalName = classSym.javaBinaryNameString classBTypeFromInternalName.getOrElse(internalName, { // The new ClassBType is added to the map in its constructor, before we set its info. This // allows initializing cyclic dependencies, see the comment on variable ClassBType._info. @@ -128,17 +134,36 @@ class BTypesFromSymbols[G <: Global](val global: G) extends BTypes { */ final def methodBTypeFromSymbol(methodSymbol: Symbol): MethodBType = { assert(methodSymbol.isMethod, s"not a method-symbol: $methodSymbol") + methodBTypeFromMethodType(methodSymbol.info, methodSymbol.isClassConstructor || methodSymbol.isConstructor) + } + + /** + * Builds a [[MethodBType]] for a method type. + */ + final def methodBTypeFromMethodType(tpe: Type, isConstructor: Boolean): MethodBType = { val resultType: BType = - if (methodSymbol.isClassConstructor || methodSymbol.isConstructor) UNIT - else typeToBType(methodSymbol.tpe.resultType) - MethodBType(methodSymbol.tpe.paramTypes map typeToBType, resultType) + if (isConstructor) UNIT + else typeToBType(tpe.resultType) + MethodBType(tpe.paramTypes map typeToBType, resultType) + } + + def bootstrapMethodArg(t: Constant, pos: Position): AnyRef = t match { + case Constant(mt: Type) => methodBTypeFromMethodType(transformedType(mt), isConstructor = false).toASMType + case c @ Constant(sym: Symbol) => staticHandleFromSymbol(sym) + case c @ Constant(value: String) => value + case c @ Constant(value) if c.isNonUnitAnyVal => c.value.asInstanceOf[AnyRef] + case _ => reporter.error(pos, "Unable to convert static argument of ApplyDynamic into a classfile constant: " + t); null + } + + def staticHandleFromSymbol(sym: Symbol): asm.Handle = { + val owner = if (sym.owner.isModuleClass) sym.owner.linkedClassOfClass else sym.owner + val descriptor = methodBTypeFromMethodType(sym.info, isConstructor = false).descriptor + val ownerBType = classBTypeFromSymbol(owner) + new asm.Handle(asm.Opcodes.H_INVOKESTATIC, ownerBType.internalName, sym.name.encoded, descriptor, /* itf = */ ownerBType.isInterface.get) } /** * This method returns the BType for a type reference, for example a parameter type. - * - * If `t` references a class, typeToBType ensures that the class is not an implementation class. - * See also comment on classBTypeFromSymbol, which is invoked for implementation classes. */ final def typeToBType(t: Type): BType = { import definitions.ArrayClass @@ -149,17 +174,16 @@ class BTypesFromSymbols[G <: Global](val global: G) extends BTypes { */ def primitiveOrClassToBType(sym: Symbol): BType = { assertClassNotArray(sym) - assert(!sym.isImplClass, sym) - primitiveTypeMap.getOrElse(sym, classBTypeFromSymbol(sym)) + primitiveTypeToBType.getOrElse(sym, classBTypeFromSymbol(sym)) } /** * When compiling Array.scala, the type parameter T is not erased and shows up in method - * signatures, e.g. `def apply(i: Int): T`. A TyperRef to T is replaced by ObjectReference. + * signatures, e.g. `def apply(i: Int): T`. A TypeRef for T is replaced by ObjectRef. */ def nonClassTypeRefToBType(sym: Symbol): ClassBType = { assert(sym.isType && isCompilingArray, sym) - ObjectReference + ObjectRef } t.dealiasWiden match { @@ -168,39 +192,24 @@ class BTypesFromSymbols[G <: Global](val global: G) extends BTypes { case TypeRef(_, sym, _) => primitiveOrClassToBType(sym) // Common reference to a type such as scala.Int or java.lang.String case ClassInfoType(_, _, sym) => primitiveOrClassToBType(sym) // We get here, for example, for genLoadModule, which invokes typeToBType(moduleClassSymbol.info) - /* AnnotatedType should (probably) be eliminated by erasure. However we know it happens for - * meta-annotated annotations (@(ann @getter) val x = 0), so we don't emit a warning. - * The type in the AnnotationInfo is an AnnotatedTpe. Tested in jvm/annotations.scala. - */ - case a @ AnnotatedType(_, t) => - debuglog(s"typeKind of annotated type $a") - typeToBType(t) - - /* ExistentialType should (probably) be eliminated by erasure. We know they get here for - * classOf constants: - * class C[T] - * class T { final val k = classOf[C[_]] } - */ - case e @ ExistentialType(_, t) => - debuglog(s"typeKind of existential type $e") - typeToBType(t) - /* The cases below should probably never occur. They are kept for now to avoid introducing * new compiler crashes, but we added a warning. The compiler / library bootstrap and the * test suite don't produce any warning. */ case tp => - currentUnit.warning(tp.typeSymbol.pos, + warning(tp.typeSymbol.pos, s"an unexpected type representation reached the compiler backend while compiling $currentUnit: $tp. " + "If possible, please file a bug on issues.scala-lang.org.") tp match { - case ThisType(ArrayClass) => ObjectReference // was introduced in 9b17332f11 to fix SI-999, but this code is not reached in its test, or any other test - case ThisType(sym) => classBTypeFromSymbol(sym) - case SingleType(_, sym) => primitiveOrClassToBType(sym) - case ConstantType(_) => typeToBType(t.underlying) - case RefinedType(parents, _) => parents.map(typeToBType(_).asClassBType).reduceLeft((a, b) => a.jvmWiseLUB(b).get) + case ThisType(ArrayClass) => ObjectRef // was introduced in 9b17332f11 to fix SI-999, but this code is not reached in its test, or any other test + case ThisType(sym) => classBTypeFromSymbol(sym) + case SingleType(_, sym) => primitiveOrClassToBType(sym) + case ConstantType(_) => typeToBType(t.underlying) + case RefinedType(parents, _) => parents.map(typeToBType(_).asClassBType).reduceLeft((a, b) => a.jvmWiseLUB(b).get) + case AnnotatedType(_, t) => typeToBType(t) + case ExistentialType(_, t) => typeToBType(t) } } } @@ -212,15 +221,109 @@ class BTypesFromSymbols[G <: Global](val global: G) extends BTypes { def assertClassNotArrayNotPrimitive(sym: Symbol): Unit = { assertClassNotArray(sym) - assert(!primitiveTypeMap.contains(sym) || isCompilingPrimitive, sym) + assert(!primitiveTypeToBType.contains(sym) || isCompilingPrimitive, sym) } + def implementedInterfaces(classSym: Symbol): List[Symbol] = { + // Additional interface parents based on annotations and other cues + def newParentForAnnotation(ann: AnnotationInfo): Option[Type] = ann.symbol match { + case RemoteAttr => Some(RemoteInterfaceClass.tpe) + case _ => None + } + + // SI-9393: java annotations are interfaces, but the classfile / java source parsers make them look like classes. + def isInterfaceOrTrait(sym: Symbol) = sym.isInterface || sym.isTrait || sym.hasJavaAnnotationFlag + + val classParents = { + val parents = classSym.info.parents + // SI-9393: the classfile / java source parsers add Annotation and ClassfileAnnotation to the + // parents of a java annotations. undo this for the backend (where we need classfile-level information). + if (classSym.hasJavaAnnotationFlag) parents.filterNot(c => c.typeSymbol == ClassfileAnnotationClass || c.typeSymbol == AnnotationClass) + else parents + } + + val allParents = classParents ++ classSym.annotations.flatMap(newParentForAnnotation) + + val minimizedParents = if (classSym.isJavaDefined) allParents else erasure.minimizeParents(allParents) + // We keep the superClass when computing minimizeParents to eliminate more interfaces. + // Example: T can be eliminated from D + // trait T + // class C extends T + // class D extends C with T + val interfaces = minimizedParents match { + case superClass :: ifs if !isInterfaceOrTrait(superClass.typeSymbol) => + ifs + case ifs => + // minimizeParents removes the superclass if it's redundant, for example: + // trait A + // class C extends Object with A // minimizeParents removes Object + ifs + } + interfaces.map(_.typeSymbol) + } + + /** + * The member classes of a class symbol. Note that the result of this method depends on the + * current phase, for example, after lambdalift, all local classes become member of the enclosing + * class. + * + * Specialized classes are always considered top-level, see comment in BTypes. + */ + private def memberClassesForInnerClassTable(classSymbol: Symbol): List[Symbol] = classSymbol.info.decls.collect({ + case sym if sym.isClass && !considerAsTopLevelImplementationArtifact(sym) => + sym + case sym if sym.isModule && !considerAsTopLevelImplementationArtifact(sym) => + val r = exitingPickler(sym.moduleClass) + assert(r != NoSymbol, sym.fullLocationString) + r + })(collection.breakOut) + private def setClassInfo(classSym: Symbol, classBType: ClassBType): ClassBType = { - // Check for isImplClass: trait implementation classes have NoSymbol as superClass + /** + * Reconstruct the classfile flags from a Java defined class symbol. + * + * The implementation of this method is slightly different from `javaFlags` in BTypesFromSymbols. + * The javaFlags method is primarily used to map Scala symbol flags to sensible classfile flags + * that are used in the generated classfiles. For example, all classes emitted by the Scala + * compiler have ACC_PUBLIC. + * + * When building a [[ClassBType]] from a Java class symbol, the flags in the type's `info` have + * to correspond exactly to the flags in the classfile. For example, if the class is package + * protected (i.e., it doesn't have the ACC_PUBLIC flag), this needs to be reflected in the + * ClassBType. For example, the inliner needs the correct flags for access checks. + * + * Class flags are listed here: + * https://docs.oracle.com/javase/specs/jvms/se7/html/jvms-4.html#jvms-4.1-200-E.1 + */ + def javaClassfileFlags(classSym: Symbol): Int = { + assert(classSym.isJava, s"Expected Java class symbol, got ${classSym.fullName}") + import asm.Opcodes._ + def enumFlags = ACC_ENUM | { + // Java enums have the `ACC_ABSTRACT` flag if they have a deferred method. + // We cannot trust `hasAbstractFlag`: the ClassfileParser adds `ABSTRACT` and `SEALED` to all + // Java enums for exhaustiveness checking. + val hasAbstractMethod = classSym.info.decls.exists(s => s.isMethod && s.isDeferred) + if (hasAbstractMethod) ACC_ABSTRACT else 0 + } + GenBCode.mkFlags( + // SI-9393: the classfile / java source parser make java annotation symbols look like classes. + // here we recover the actual classfile flags. + if (classSym.hasJavaAnnotationFlag) ACC_ANNOTATION | ACC_INTERFACE | ACC_ABSTRACT else 0, + if (classSym.isPublic) ACC_PUBLIC else 0, + if (classSym.isFinal) ACC_FINAL else 0, + // see the link above. javac does the same: ACC_SUPER for all classes, but not interfaces. + if (classSym.isInterface) ACC_INTERFACE else ACC_SUPER, + // for Java enums, we cannot trust `hasAbstractFlag` (see comment in enumFlags) + if (!classSym.hasJavaEnumFlag && classSym.hasAbstractFlag) ACC_ABSTRACT else 0, + if (classSym.isArtifact) ACC_SYNTHETIC else 0, + if (classSym.hasJavaEnumFlag) enumFlags else 0 + ) + } + // Check for hasAnnotationFlag for SI-9393: the classfile / java source parsers add // scala.annotation.Annotation as superclass to java annotations. In reality, java // annotation classfiles have superclass Object (like any interface classfile). - val superClassSym = if (classSym.isImplClass || classSym.hasJavaAnnotationFlag) ObjectClass else { + val superClassSym = if (classSym.hasJavaAnnotationFlag) ObjectClass else { val sc = classSym.superClass // SI-9393: Java annotation classes don't have the ABSTRACT/INTERFACE flag, so they appear // (wrongly) as superclasses. Fix this for BTypes: the java annotation will appear as interface @@ -235,7 +338,7 @@ class BTypesFromSymbols[G <: Global](val global: G) extends BTypes { superClassSym == ObjectClass else // A ClassBType for a primitive class (scala.Boolean et al) is only created when compiling these classes. - ((superClassSym != NoSymbol) && !superClassSym.isInterface) || (isCompilingPrimitive && primitiveTypeMap.contains(classSym)), + ((superClassSym != NoSymbol) && !superClassSym.isInterface) || (isCompilingPrimitive && primitiveTypeToBType.contains(classSym)), s"Bad superClass for $classSym: $superClassSym" ) val superClass = if (superClassSym == NoSymbol) None @@ -251,13 +354,6 @@ class BTypesFromSymbols[G <: Global](val global: G) extends BTypes { /* The InnerClass table of a class C must contain all nested classes of C, even if they are only * declared but not otherwise referenced in C (from the bytecode or a method / field signature). * We collect them here. - * - * Nested classes that are also referenced in C will be added to the innerClassBufferASM during - * code generation, but those duplicates will be eliminated when emitting the InnerClass - * attribute. - * - * Why do we need to collect classes into innerClassBufferASM at all? To collect references to - * nested classes, but NOT nested in C, that are used within C. */ val nestedClassSymbols = { val linkedClass = exitingPickler(classSym.linkedClassOfClass) // linkedCoC does not work properly in late phases @@ -286,8 +382,8 @@ class BTypesFromSymbols[G <: Global](val global: G) extends BTypes { } val companionModuleMembers = if (considerAsTopLevelImplementationArtifact(classSym)) Nil else { - // If this is a top-level non-impl (*) class, the member classes of the companion object are - // added as members of the class. For example: + // If this is a top-level class, the member classes of the companion object are added as + // members of the class. For example: // class C { } // object C { // class D @@ -298,11 +394,6 @@ class BTypesFromSymbols[G <: Global](val global: G) extends BTypes { // (done by buildNestedInfo). See comment in BTypes. // For consistency, the InnerClass entry for D needs to be present in C - to Java it looks // like D is a member of C, not C$. - // - // (*) We exclude impl classes: if the classfile for the impl class exists on the classpath, - // a linkedClass symbol is found for which isTopLevelModule is true, so we end up searching - // members of that weird impl-class-module-class-symbol. that search probably cannot return - // any classes, but it's better to exclude it. val javaCompatMembers = { if (linkedClass != NoSymbol && isTopLevelModuleClass(linkedClass)) // phase travel to exitingPickler: this makes sure that memberClassesForInnerClassTable only sees member @@ -360,7 +451,7 @@ class BTypesFromSymbols[G <: Global](val global: G) extends BTypes { assert(innerClassSym.isClass, s"Cannot build NestedInfo for non-class symbol $innerClassSym") val isTopLevel = innerClassSym.rawowner.isPackageClass - // impl classes are considered top-level, see comment in BTypes + // specialized classes are considered top-level, see comment in BTypes if (isTopLevel || considerAsTopLevelImplementationArtifact(innerClassSym)) None else if (innerClassSym.rawowner.isTerm) { // This case should never be reached: the lambdalift phase mutates the rawowner field of all @@ -428,13 +519,13 @@ class BTypesFromSymbols[G <: Global](val global: G) extends BTypes { * classfile attribute. */ private def buildInlineInfo(classSym: Symbol, internalName: InternalName): InlineInfo = { - def buildFromSymbol = buildInlineInfoFromClassSymbol(classSym, classBTypeFromSymbol(_).internalName, methodBTypeFromSymbol(_).descriptor) + def buildFromSymbol = buildInlineInfoFromClassSymbol(classSym) // phase travel required, see implementation of `compiles`. for nested classes, it checks if the // enclosingTopLevelClass is being compiled. after flatten, all classes are considered top-level, // so `compiles` would return `false`. if (exitingPickler(currentRun.compiles(classSym))) buildFromSymbol // InlineInfo required for classes being compiled, we have to create the classfile attribute - else if (!compilerSettings.YoptInlinerEnabled) BTypes.EmptyInlineInfo // For other classes, we need the InlineInfo only inf the inliner is enabled. + else if (!compilerSettings.optInlinerEnabled) BTypes.EmptyInlineInfo // For other classes, we need the InlineInfo only inf the inliner is enabled. else { // For classes not being compiled, the InlineInfo is read from the classfile attribute. This // fixes an issue with mixed-in methods: the mixin phase enters mixin methods only to class @@ -444,30 +535,123 @@ class BTypesFromSymbols[G <: Global](val global: G) extends BTypes { case Right(classNode) => inlineInfoFromClassfile(classNode) case Left(missingClass) => - InlineInfo(None, false, Map.empty, Some(ClassNotFoundWhenBuildingInlineInfoFromSymbol(missingClass))) + EmptyInlineInfo.copy(warning = Some(ClassNotFoundWhenBuildingInlineInfoFromSymbol(missingClass))) + } + } + } + + /** + * Build the [[InlineInfo]] for a class symbol. + */ + def buildInlineInfoFromClassSymbol(classSym: Symbol): InlineInfo = { + val isEffectivelyFinal = classSym.isEffectivelyFinal + + val sam = { + if (classSym.isEffectivelyFinal) None + else { + // Phase travel necessary. For example, nullary methods (getter of an abstract val) get an + // empty parameter list in uncurry and would therefore be picked as SAM. + // Similarly, the fields phases adds abstract trait setters, which should not be considered + // abstract for SAMs (they do disqualify the SAM from LMF treatment, + // but an anonymous subclasss can be spun up by scalac after making just the single abstract method concrete) + val samSym = exitingPickler(definitions.samOf(classSym.tpe)) + if (samSym == NoSymbol) None + else Some(samSym.javaSimpleName.toString + methodBTypeFromSymbol(samSym).descriptor) } } + + var warning = Option.empty[ClassSymbolInfoFailureSI9111] + + def keepMember(sym: Symbol) = sym.isMethod && !scalaPrimitives.isPrimitive(sym) + val classMethods = classSym.info.decls.iterator.filter(keepMember) + val methods = if (!classSym.isJavaDefined) classMethods else { + val staticMethods = classSym.companionModule.info.decls.iterator.filter(m => !m.isConstructor && keepMember(m)) + staticMethods ++ classMethods + } + + // Primitive methods cannot be inlined, so there's no point in building a MethodInlineInfo. Also, some + // primitive methods (e.g., `isInstanceOf`) have non-erased types, which confuses [[typeToBType]]. + val methodInlineInfos = methods.flatMap({ + case methodSym => + if (completeSilentlyAndCheckErroneous(methodSym)) { + // Happens due to SI-9111. Just don't provide any MethodInlineInfo for that method, we don't need fail the compiler. + if (!classSym.isJavaDefined) devWarning("SI-9111 should only be possible for Java classes") + warning = Some(ClassSymbolInfoFailureSI9111(classSym.fullName)) + Nil + } else { + val name = methodSym.javaSimpleName.toString // same as in genDefDef + val signature = name + methodBTypeFromSymbol(methodSym).descriptor + + // In `trait T { object O }`, `oSym.isEffectivelyFinalOrNotOverridden` is true, but the + // method is abstract in bytecode, `defDef.rhs.isEmpty`. Abstract methods are excluded + // so they are not marked final in the InlineInfo attribute. + // + // However, due to https://github.com/scala/scala-dev/issues/126, this currently does not + // work, the abstract accessor for O will be marked effectivelyFinal. + val effectivelyFinal = methodSym.isEffectivelyFinalOrNotOverridden && !(methodSym hasFlag DEFERRED | SYNTHESIZE_IMPL_IN_SUBCLASS) + + val info = MethodInlineInfo( + effectivelyFinal = effectivelyFinal, + annotatedInline = methodSym.hasAnnotation(ScalaInlineClass), + annotatedNoInline = methodSym.hasAnnotation(ScalaNoInlineClass)) + + if (needsStaticImplMethod(methodSym)) { + val staticName = traitSuperAccessorName(methodSym).toString + val selfParam = methodSym.newSyntheticValueParam(methodSym.owner.typeConstructor, nme.SELF) + val staticMethodType = methodSym.info match { + case mt @ MethodType(params, res) => copyMethodType(mt, selfParam :: params, res) + } + val staticMethodSignature = staticName + methodBTypeFromMethodType(staticMethodType, isConstructor = false) + val staticMethodInfo = MethodInlineInfo( + effectivelyFinal = true, + annotatedInline = info.annotatedInline, + annotatedNoInline = info.annotatedNoInline) + if (methodSym.isMixinConstructor) + List((staticMethodSignature, staticMethodInfo)) + else + List((signature, info), (staticMethodSignature, staticMethodInfo)) + } else + List((signature, info)) + } + }).toMap + + InlineInfo(isEffectivelyFinal, sam, methodInlineInfos, warning) } /** - * For top-level objects without a companion class, the compilere generates a mirror class with + * For top-level objects without a companion class, the compiler generates a mirror class with * static forwarders (Java compat). There's no symbol for the mirror class, but we still need a * ClassBType (its info.nestedClasses will hold the InnerClass entries, see comment in BTypes). */ def mirrorClassClassBType(moduleClassSym: Symbol): ClassBType = { assert(isTopLevelModuleClass(moduleClassSym), s"not a top-level module class: $moduleClassSym") - val internalName = moduleClassSym.javaBinaryName.dropModule.toString + val internalName = moduleClassSym.javaBinaryNameString.stripSuffix(nme.MODULE_SUFFIX_STRING) classBTypeFromInternalName.getOrElse(internalName, { val c = ClassBType(internalName) // class info consistent with BCodeHelpers.genMirrorClass val nested = exitingPickler(memberClassesForInnerClassTable(moduleClassSym)) map classBTypeFromSymbol c.info = Right(ClassInfo( - superClass = Some(ObjectReference), + superClass = Some(ObjectRef), interfaces = Nil, flags = asm.Opcodes.ACC_SUPER | asm.Opcodes.ACC_PUBLIC | asm.Opcodes.ACC_FINAL, nestedClasses = nested, nestedInfo = None, - InlineInfo(None, true, Map.empty, None))) // no InlineInfo needed, scala never invokes methods on the mirror class + inlineInfo = EmptyInlineInfo.copy(isEffectivelyFinal = true))) // no method inline infos needed, scala never invokes methods on the mirror class + c + }) + } + + def beanInfoClassClassBType(mainClass: Symbol): ClassBType = { + val internalName = mainClass.javaBinaryNameString + "BeanInfo" + classBTypeFromInternalName.getOrElse(internalName, { + val c = ClassBType(internalName) + c.info = Right(ClassInfo( + superClass = Some(sbScalaBeanInfoRef), + interfaces = Nil, + flags = javaFlags(mainClass), + nestedClasses = Nil, + nestedInfo = None, + inlineInfo = EmptyInlineInfo)) c }) } @@ -478,26 +662,16 @@ class BTypesFromSymbols[G <: Global](val global: G) extends BTypes { */ final def isTopLevelModuleClass(sym: Symbol): Boolean = exitingPickler { // phase travel to pickler required for isNestedClass (looks at owner) - val r = sym.isModuleClass && !sym.isNestedClass - // The mixin phase adds the `lateMODULE` flag to trait implementation classes. Since the flag - // is late, it should not be visible here inside the time travel. We check this. - if (r) assert(!sym.isImplClass, s"isModuleClass should be false for impl class $sym") - r + sym.isModuleClass && !sym.isNestedClass } /** * True for module classes of modules that are top-level or owned only by objects. Module classes - * for such objects will get a MODULE$ flag and a corresponding static initializer. + * for such objects will get a MODULE$ field and a corresponding static initializer. */ final def isStaticModuleClass(sym: Symbol): Boolean = { - /* (1) Phase travel to to pickler is required to exclude implementation classes; they have the - * lateMODULEs after mixin, so isModuleClass would be true. - * (2) isStaticModuleClass is a source-level property. See comment on isOriginallyStaticOwner. - */ - exitingPickler { // (1) - sym.isModuleClass && - isOriginallyStaticOwner(sym.originalOwner) // (2) - } + sym.isModuleClass && + isOriginallyStaticOwner(sym.originalOwner) // isStaticModuleClass is a source-level property, see comment on isOriginallyStaticOwner } // legacy, to be removed when the @remote annotation gets removed @@ -550,34 +724,28 @@ class BTypesFromSymbols[G <: Global](val global: G) extends BTypes { // scala compiler. The word final is heavily overloaded unfortunately; // for us it means "not overridable". At present you can't override // vars regardless; this may change. - // - // The logic does not check .isFinal (which checks flags for the FINAL flag, - // and includes symbols marked lateFINAL) instead inspecting rawflags so - // we can exclude lateFINAL. Such symbols are eligible for inlining, but to - // avoid breaking proxy software which depends on subclassing, we do not - // emit ACC_FINAL. val finalFlag = ( - (((sym.rawflags & symtab.Flags.FINAL) != 0) || isTopLevelModuleClass(sym)) - && !sym.enclClass.isInterface + (sym.isFinal || isTopLevelModuleClass(sym)) + && !sym.enclClass.isTrait && !sym.isClassConstructor - && !sym.isMutable // lazy vals and vars both + && (!sym.isMutable || nme.isTraitSetterName(sym.name)) // lazy vals and vars and their setters cannot be final, but trait setters are ) // Primitives are "abstract final" to prohibit instantiation // without having to provide any implementations, but that is an // illegal combination of modifiers at the bytecode level so - // suppress final if abstract if present. + // suppress final if abstract is present. import asm.Opcodes._ GenBCode.mkFlags( if (privateFlag) ACC_PRIVATE else ACC_PUBLIC, - if (sym.isDeferred || sym.hasAbstractFlag) ACC_ABSTRACT else 0, - if (sym.isInterface) ACC_INTERFACE else 0, + if ((sym.isDeferred && !sym.hasFlag(symtab.Flags.JAVA_DEFAULTMETHOD))|| sym.hasAbstractFlag) ACC_ABSTRACT else 0, + if (sym.isTraitOrInterface) ACC_INTERFACE else 0, if (finalFlag && !sym.hasAbstractFlag) ACC_FINAL else 0, if (sym.isStaticMember) ACC_STATIC else 0, if (sym.isBridge) ACC_BRIDGE | ACC_SYNTHETIC else 0, if (sym.isArtifact) ACC_SYNTHETIC else 0, - if (sym.isClass && !sym.isInterface) ACC_SUPER else 0, + if (sym.isClass && !sym.isTraitOrInterface) ACC_SUPER else 0, if (sym.hasJavaEnumFlag) ACC_ENUM else 0, if (sym.isVarargsMethod) ACC_VARARGS else 0, if (sym.hasFlag(symtab.Flags.SYNCHRONIZED)) ACC_SYNCHRONIZED else 0, diff --git a/src/compiler/scala/tools/nsc/backend/jvm/BackendReporting.scala b/src/compiler/scala/tools/nsc/backend/jvm/BackendReporting.scala index b41d0de92f..e6ae073a2a 100644 --- a/src/compiler/scala/tools/nsc/backend/jvm/BackendReporting.scala +++ b/src/compiler/scala/tools/nsc/backend/jvm/BackendReporting.scala @@ -1,7 +1,7 @@ package scala.tools.nsc package backend.jvm -import scala.tools.asm.tree.{InvokeDynamicInsnNode, AbstractInsnNode, MethodNode} +import scala.tools.asm.tree.{AbstractInsnNode, MethodNode} import scala.tools.nsc.backend.jvm.BTypes.InternalName import scala.reflect.internal.util.Position import scala.tools.nsc.settings.ScalaSettings @@ -26,9 +26,7 @@ final class BackendReportingImpl(val global: Global) extends BackendReporting { /** * Utilities for error reporting. * - * Defines some tools to make error reporting with Either easier. Would be subsumed by a right-biased - * Either in the standard library (or scalaz \/) (Validation is different, it accumulates multiple - * errors). + * Defines some utility methods to make error reporting with Either easier. */ object BackendReporting { def methodSignature(classInternalName: InternalName, name: String, desc: String) = { @@ -42,19 +40,12 @@ object BackendReporting { def assertionError(message: String): Nothing = throw new AssertionError(message) implicit class RightBiasedEither[A, B](val v: Either[A, B]) extends AnyVal { - def map[U](f: B => U) = v.right.map(f) - def flatMap[BB](f: B => Either[A, BB]) = v.right.flatMap(f) - def filter(f: B => Boolean)(implicit empty: A): Either[A, B] = v match { + def withFilter(f: B => Boolean)(implicit empty: A): Either[A, B] = v match { case Left(_) => v case Right(e) => if (f(e)) v else Left(empty) // scalaz.\/ requires an implicit Monoid m to get m.empty } - def foreach[U](f: B => U) = v.right.foreach(f) - def getOrElse[BB >: B](alt: => BB): BB = v.right.getOrElse(alt) - - /** - * Get the value, fail with an assertion if this is an error. - */ + /** Get the value, fail with an assertion if this is an error. */ def get: B = { assert(v.isRight, v.left.get) v.right.get @@ -86,8 +77,8 @@ object BackendReporting { def emitWarning(settings: ScalaSettings): Boolean } - // Method filter in RightBiasedEither requires an implicit empty value. Taking the value here - // in scope allows for-comprehensions that desugar into filter calls (for example when using a + // Method withFilter in RightBiasedEither requires an implicit empty value. Taking the value here + // in scope allows for-comprehensions that desugar into withFilter calls (for example when using a // tuple de-constructor). implicit object emptyOptimizerWarning extends OptimizerWarning { def emitWarning(settings: ScalaSettings): Boolean = false @@ -101,11 +92,14 @@ object BackendReporting { else "" } - case MethodNotFound(name, descriptor, ownerInternalName, missingClasses) => - val (javaDef, others) = missingClasses.partition(_.definedInJavaSource) - s"The method $name$descriptor could not be found in the class $ownerInternalName or any of its parents." + - (if (others.isEmpty) "" else others.map(_.internalName).mkString("\nNote that the following parent classes could not be found on the classpath: ", ", ", "")) + - (if (javaDef.isEmpty) "" else javaDef.map(_.internalName).mkString("\nNote that the following parent classes are defined in Java sources (mixed compilation), no bytecode is available: ", ",", "")) + case MethodNotFound(name, descriptor, ownerInternalName, missingClass) => + val missingClassWarning = missingClass match { + case None => "" + case Some(c) => + if (c.definedInJavaSource) s"\nNote that class ${c.internalName} is defined in a Java source (mixed compilation), no bytecode is available." + else s"\nNote that class ${c.internalName} could not be found on the classpath." + } + s"The method $name$descriptor could not be found in the class $ownerInternalName or any of its parents." + missingClassWarning case FieldNotFound(name, descriptor, ownerInternalName, missingClass) => s"The field node $name$descriptor could not be found because the classfile $ownerInternalName cannot be found on the classpath." + @@ -114,20 +108,20 @@ object BackendReporting { def emitWarning(settings: ScalaSettings): Boolean = this match { case ClassNotFound(_, javaDefined) => - if (javaDefined) settings.YoptWarningNoInlineMixed - else settings.YoptWarningNoInlineMissingBytecode + if (javaDefined) settings.optWarningNoInlineMixed + else settings.optWarningNoInlineMissingBytecode case m @ MethodNotFound(_, _, _, missing) => if (m.isArrayMethod) false - else settings.YoptWarningNoInlineMissingBytecode || missing.exists(_.emitWarning(settings)) + else settings.optWarningNoInlineMissingBytecode || missing.exists(_.emitWarning(settings)) case FieldNotFound(_, _, _, missing) => - settings.YoptWarningNoInlineMissingBytecode || missing.exists(_.emitWarning(settings)) + settings.optWarningNoInlineMissingBytecode || missing.exists(_.emitWarning(settings)) } } case class ClassNotFound(internalName: InternalName, definedInJavaSource: Boolean) extends MissingBytecodeWarning - case class MethodNotFound(name: String, descriptor: String, ownerInternalNameOrArrayDescriptor: InternalName, missingClasses: List[ClassNotFound]) extends MissingBytecodeWarning { + case class MethodNotFound(name: String, descriptor: String, ownerInternalNameOrArrayDescriptor: InternalName, missingClass: Option[ClassNotFound]) extends MissingBytecodeWarning { def isArrayMethod = ownerInternalNameOrArrayDescriptor.charAt(0) == '[' } case class FieldNotFound(name: String, descriptor: String, ownerInternalName: InternalName, missingClass: Option[ClassNotFound]) extends MissingBytecodeWarning @@ -143,7 +137,7 @@ object BackendReporting { def emitWarning(settings: ScalaSettings): Boolean = this match { case NoClassBTypeInfoMissingBytecode(cause) => cause.emitWarning(settings) - case NoClassBTypeInfoClassSymbolInfoFailedSI9111(_) => settings.YoptWarningNoInlineMissingBytecode + case NoClassBTypeInfoClassSymbolInfoFailedSI9111(_) => settings.optWarningNoInlineMissingBytecode } } @@ -170,85 +164,89 @@ object BackendReporting { case MethodInlineInfoError(_, _, _, cause) => s"Error while computing the inline information for method $warningMessageSignature:\n" + cause - - case RewriteTraitCallToStaticImplMethodFailed(_, _, _, cause) => - cause.toString } def emitWarning(settings: ScalaSettings): Boolean = this match { case MethodInlineInfoIncomplete(_, _, _, cause) => cause.emitWarning(settings) case MethodInlineInfoMissing(_, _, _, Some(cause)) => cause.emitWarning(settings) - case MethodInlineInfoMissing(_, _, _, None) => settings.YoptWarningNoInlineMissingBytecode + case MethodInlineInfoMissing(_, _, _, None) => settings.optWarningNoInlineMissingBytecode case MethodInlineInfoError(_, _, _, cause) => cause.emitWarning(settings) - - case RewriteTraitCallToStaticImplMethodFailed(_, _, _, cause) => cause.emitWarning(settings) } } case class MethodInlineInfoIncomplete(declarationClass: InternalName, name: String, descriptor: String, cause: ClassInlineInfoWarning) extends CalleeInfoWarning case class MethodInlineInfoMissing(declarationClass: InternalName, name: String, descriptor: String, cause: Option[ClassInlineInfoWarning]) extends CalleeInfoWarning case class MethodInlineInfoError(declarationClass: InternalName, name: String, descriptor: String, cause: NoClassBTypeInfo) extends CalleeInfoWarning - case class RewriteTraitCallToStaticImplMethodFailed(declarationClass: InternalName, name: String, descriptor: String, cause: OptimizerWarning) extends CalleeInfoWarning sealed trait CannotInlineWarning extends OptimizerWarning { def calleeDeclarationClass: InternalName def name: String def descriptor: String - def calleeMethodSig = BackendReporting.methodSignature(calleeDeclarationClass, name, descriptor) + /** Either the callee or the callsite is annotated @inline */ + def annotatedInline: Boolean - override def toString = this match { - case IllegalAccessInstruction(_, _, _, callsiteClass, instruction) => - s"The callee $calleeMethodSig contains the instruction ${AsmUtils.textify(instruction)}" + - s"\nthat would cause an IllegalAccessError when inlined into class $callsiteClass." - - case IllegalAccessCheckFailed(_, _, _, callsiteClass, instruction, cause) => - s"Failed to check if $calleeMethodSig can be safely inlined to $callsiteClass without causing an IllegalAccessError. Checking instruction ${AsmUtils.textify(instruction)} failed:\n" + cause - - case MethodWithHandlerCalledOnNonEmptyStack(_, _, _, callsiteClass, callsiteName, callsiteDesc) => - s"""The operand stack at the callsite in ${BackendReporting.methodSignature(callsiteClass, callsiteName, callsiteDesc)} contains more values than the - |arguments expected by the callee $calleeMethodSig. These values would be discarded - |when entering an exception handler declared in the inlined method.""".stripMargin - - case SynchronizedMethod(_, _, _) => - s"Method $calleeMethodSig cannot be inlined because it is synchronized." + def calleeMethodSig = BackendReporting.methodSignature(calleeDeclarationClass, name, descriptor) - case StrictfpMismatch(_, _, _, callsiteClass, callsiteName, callsiteDesc) => - s"""The callsite method ${BackendReporting.methodSignature(callsiteClass, callsiteName, callsiteDesc)} - |does not have the same strictfp mode as the callee $calleeMethodSig. + override def toString = { + val annotWarn = if (annotatedInline) " is annotated @inline but" else "" + val warning = s"$calleeMethodSig$annotWarn could not be inlined:\n" + val reason = this match { + case CalleeNotFinal(_, _, _, _) => + s"The method is not final and may be overridden." + case IllegalAccessInstruction(_, _, _, _, callsiteClass, instruction) => + s"The callee $calleeMethodSig contains the instruction ${AsmUtils.textify(instruction)}" + + s"\nthat would cause an IllegalAccessError when inlined into class $callsiteClass." + + case IllegalAccessCheckFailed(_, _, _, _, callsiteClass, instruction, cause) => + s"Failed to check if $calleeMethodSig can be safely inlined to $callsiteClass without causing an IllegalAccessError. Checking instruction ${AsmUtils.textify(instruction)} failed:\n" + cause + + case MethodWithHandlerCalledOnNonEmptyStack(_, _, _, _, callsiteClass, callsiteName, callsiteDesc) => + s"""The operand stack at the callsite in ${BackendReporting.methodSignature(callsiteClass, callsiteName, callsiteDesc)} contains more values than the + |arguments expected by the callee $calleeMethodSig. These values would be discarded + |when entering an exception handler declared in the inlined method.""".stripMargin + + case SynchronizedMethod(_, _, _, _) => + s"Method $calleeMethodSig cannot be inlined because it is synchronized." + + case StrictfpMismatch(_, _, _, _, callsiteClass, callsiteName, callsiteDesc) => + s"""The callsite method ${BackendReporting.methodSignature(callsiteClass, callsiteName, callsiteDesc)} + |does not have the same strictfp mode as the callee $calleeMethodSig. """.stripMargin - case ResultingMethodTooLarge(_, _, _, callsiteClass, callsiteName, callsiteDesc) => - s"""The size of the callsite method ${BackendReporting.methodSignature(callsiteClass, callsiteName, callsiteDesc)} - |would exceed the JVM method size limit after inlining $calleeMethodSig. + case ResultingMethodTooLarge(_, _, _, _, callsiteClass, callsiteName, callsiteDesc) => + s"""The size of the callsite method ${BackendReporting.methodSignature(callsiteClass, callsiteName, callsiteDesc)} + |would exceed the JVM method size limit after inlining $calleeMethodSig. """.stripMargin + } + warning + reason } - def emitWarning(settings: ScalaSettings): Boolean = this match { - case _: IllegalAccessInstruction | _: MethodWithHandlerCalledOnNonEmptyStack | _: SynchronizedMethod | _: StrictfpMismatch | _: ResultingMethodTooLarge => - settings.YoptWarningEmitAtInlineFailed - - case IllegalAccessCheckFailed(_, _, _, _, _, cause) => - cause.emitWarning(settings) + def emitWarning(settings: ScalaSettings): Boolean = { + settings.optWarnings.contains(settings.optWarningsChoices.anyInlineFailed) || + annotatedInline && settings.optWarningEmitAtInlineFailed } } - case class IllegalAccessInstruction(calleeDeclarationClass: InternalName, name: String, descriptor: String, + case class CalleeNotFinal(calleeDeclarationClass: InternalName, name: String, descriptor: String, annotatedInline: Boolean) extends CannotInlineWarning + case class IllegalAccessInstruction(calleeDeclarationClass: InternalName, name: String, descriptor: String, annotatedInline: Boolean, callsiteClass: InternalName, instruction: AbstractInsnNode) extends CannotInlineWarning - case class IllegalAccessCheckFailed(calleeDeclarationClass: InternalName, name: String, descriptor: String, + case class IllegalAccessCheckFailed(calleeDeclarationClass: InternalName, name: String, descriptor: String, annotatedInline: Boolean, callsiteClass: InternalName, instruction: AbstractInsnNode, cause: OptimizerWarning) extends CannotInlineWarning - case class MethodWithHandlerCalledOnNonEmptyStack(calleeDeclarationClass: InternalName, name: String, descriptor: String, + case class MethodWithHandlerCalledOnNonEmptyStack(calleeDeclarationClass: InternalName, name: String, descriptor: String, annotatedInline: Boolean, callsiteClass: InternalName, callsiteName: String, callsiteDesc: String) extends CannotInlineWarning - case class SynchronizedMethod(calleeDeclarationClass: InternalName, name: String, descriptor: String) extends CannotInlineWarning - case class StrictfpMismatch(calleeDeclarationClass: InternalName, name: String, descriptor: String, + case class SynchronizedMethod(calleeDeclarationClass: InternalName, name: String, descriptor: String, annotatedInline: Boolean) extends CannotInlineWarning + case class StrictfpMismatch(calleeDeclarationClass: InternalName, name: String, descriptor: String, annotatedInline: Boolean, callsiteClass: InternalName, callsiteName: String, callsiteDesc: String) extends CannotInlineWarning - case class ResultingMethodTooLarge(calleeDeclarationClass: InternalName, name: String, descriptor: String, + case class ResultingMethodTooLarge(calleeDeclarationClass: InternalName, name: String, descriptor: String, annotatedInline: Boolean, callsiteClass: InternalName, callsiteName: String, callsiteDesc: String) extends CannotInlineWarning + // TODO: this should be a subtype of CannotInlineWarning + // but at the place where it's created (in findIllegalAccess) we don't have the necessary data (calleeName, calleeDescriptor). case object UnknownInvokeDynamicInstruction extends OptimizerWarning { override def toString = "The callee contains an InvokeDynamic instruction with an unknown bootstrap method (not a LambdaMetaFactory)." - def emitWarning(settings: ScalaSettings): Boolean = settings.YoptWarningEmitAtInlineFailed + def emitWarning(settings: ScalaSettings): Boolean = settings.optWarnings.contains(settings.optWarningsChoices.anyInlineFailed) } /** @@ -260,7 +258,7 @@ object BackendReporting { override def emitWarning(settings: ScalaSettings): Boolean = this match { case RewriteClosureAccessCheckFailed(_, cause) => cause.emitWarning(settings) - case RewriteClosureIllegalAccess(_, _) => settings.YoptWarningEmitAtInlineFailed + case RewriteClosureIllegalAccess(_, _) => settings.optWarnings.contains(settings.optWarningsChoices.anyInlineFailed) } override def toString: String = this match { @@ -285,17 +283,17 @@ object BackendReporting { s"Failed to get the type of a method of class symbol $classFullName due to SI-9111." case ClassNotFoundWhenBuildingInlineInfoFromSymbol(missingClass) => - s"Failed to build the inline information: $missingClass." + s"Failed to build the inline information: $missingClass" case UnknownScalaInlineInfoVersion(internalName, version) => s"Cannot read ScalaInlineInfo version $version in classfile $internalName. Use a more recent compiler." } def emitWarning(settings: ScalaSettings): Boolean = this match { - case NoInlineInfoAttribute(_) => settings.YoptWarningNoInlineMissingScalaInlineInfoAttr + case NoInlineInfoAttribute(_) => settings.optWarningNoInlineMissingScalaInlineInfoAttr case ClassNotFoundWhenBuildingInlineInfoFromSymbol(cause) => cause.emitWarning(settings) - case ClassSymbolInfoFailureSI9111(_) => settings.YoptWarningNoInlineMissingBytecode - case UnknownScalaInlineInfoVersion(_, _) => settings.YoptWarningNoInlineMissingScalaInlineInfoAttr + case ClassSymbolInfoFailureSI9111(_) => settings.optWarningNoInlineMissingBytecode + case UnknownScalaInlineInfoVersion(_, _) => settings.optWarningNoInlineMissingScalaInlineInfoAttr } } diff --git a/src/compiler/scala/tools/nsc/backend/jvm/BackendStats.scala b/src/compiler/scala/tools/nsc/backend/jvm/BackendStats.scala index 03306f30aa..8d0547b607 100644 --- a/src/compiler/scala/tools/nsc/backend/jvm/BackendStats.scala +++ b/src/compiler/scala/tools/nsc/backend/jvm/BackendStats.scala @@ -8,6 +8,7 @@ package backend.jvm import scala.reflect.internal.util.Statistics +// Enable with `-Ystatistics:jvm` object BackendStats { import Statistics.{newTimer, newSubTimer} val bcodeTimer = newTimer("time in backend", "jvm") diff --git a/src/compiler/scala/tools/nsc/backend/jvm/BytecodeWriters.scala b/src/compiler/scala/tools/nsc/backend/jvm/BytecodeWriters.scala index 1d29fdee10..2cf5cfcb8d 100644 --- a/src/compiler/scala/tools/nsc/backend/jvm/BytecodeWriters.scala +++ b/src/compiler/scala/tools/nsc/backend/jvm/BytecodeWriters.scala @@ -6,7 +6,7 @@ package scala.tools.nsc package backend.jvm -import java.io.{ DataOutputStream, FileOutputStream, IOException, OutputStream, File => JFile } +import java.io.{ DataOutputStream, FileOutputStream, IOException, File => JFile } import scala.tools.nsc.io._ import java.util.jar.Attributes.Name import scala.language.postfixOps @@ -78,7 +78,7 @@ trait BytecodeWriters { } /* - * The ASM textual representation for bytecode overcomes disadvantages of javap ouput in three areas: + * The ASM textual representation for bytecode overcomes disadvantages of javap output in three areas: * (a) pickle dingbats undecipherable to the naked eye; * (b) two constant pools, while having identical contents, are displayed differently due to physical layout. * (c) stack maps (classfile version 50 and up) are displayed in encoded form by javap, diff --git a/src/compiler/scala/tools/nsc/backend/jvm/CoreBTypes.scala b/src/compiler/scala/tools/nsc/backend/jvm/CoreBTypes.scala index 00ca096e59..acb950929f 100644 --- a/src/compiler/scala/tools/nsc/backend/jvm/CoreBTypes.scala +++ b/src/compiler/scala/tools/nsc/backend/jvm/CoreBTypes.scala @@ -1,7 +1,8 @@ package scala.tools.nsc package backend.jvm -import scala.annotation.switch +import scala.tools.asm +import scala.tools.nsc.backend.jvm.BTypes.InternalName /** * Core BTypes and some other definitions. The initialization of these definitions requires access @@ -9,7 +10,7 @@ import scala.annotation.switch * * The symbols used to initialize the ClassBTypes may change from one compiler run to the next. To * make sure the definitions are consistent with the symbols in the current run, the - * `intializeCoreBTypes` method in BTypesFromSymbols creates a new instance of CoreBTypes in each + * `initializeCoreBTypes` method in BTypesFromSymbols creates a new instance of CoreBTypes in each * compiler run. * * The class BTypesFromSymbols does not directly reference CoreBTypes, but CoreBTypesProxy. The @@ -29,14 +30,14 @@ import scala.annotation.switch class CoreBTypes[BTFS <: BTypesFromSymbols[_ <: Global]](val bTypes: BTFS) { import bTypes._ import global._ - import rootMirror.{requiredClass, getClassIfDefined} + import rootMirror.{requiredClass, getRequiredClass, getClassIfDefined} import definitions._ /** * Maps primitive types to their corresponding PrimitiveBType. The map is defined lexically above * the first use of `classBTypeFromSymbol` because that method looks at the map. */ - lazy val primitiveTypeMap: Map[Symbol, PrimitiveBType] = Map( + lazy val primitiveTypeToBType: Map[Symbol, PrimitiveBType] = Map( UnitClass -> UNIT, BooleanClass -> BOOL, CharClass -> CHAR, @@ -45,34 +46,22 @@ class CoreBTypes[BTFS <: BTypesFromSymbols[_ <: Global]](val bTypes: BTFS) { IntClass -> INT, LongClass -> LONG, FloatClass -> FLOAT, - DoubleClass -> DOUBLE - ) - - lazy val BOXED_UNIT : ClassBType = classBTypeFromSymbol(requiredClass[java.lang.Void]) - lazy val BOXED_BOOLEAN : ClassBType = classBTypeFromSymbol(BoxedBooleanClass) - lazy val BOXED_BYTE : ClassBType = classBTypeFromSymbol(BoxedByteClass) - lazy val BOXED_SHORT : ClassBType = classBTypeFromSymbol(BoxedShortClass) - lazy val BOXED_CHAR : ClassBType = classBTypeFromSymbol(BoxedCharacterClass) - lazy val BOXED_INT : ClassBType = classBTypeFromSymbol(BoxedIntClass) - lazy val BOXED_LONG : ClassBType = classBTypeFromSymbol(BoxedLongClass) - lazy val BOXED_FLOAT : ClassBType = classBTypeFromSymbol(BoxedFloatClass) - lazy val BOXED_DOUBLE : ClassBType = classBTypeFromSymbol(BoxedDoubleClass) + DoubleClass -> DOUBLE) /** * Map from primitive types to their boxed class type. Useful when pushing class literals onto the * operand stack (ldc instruction taking a class literal), see genConstant. */ lazy val boxedClassOfPrimitive: Map[PrimitiveBType, ClassBType] = Map( - UNIT -> BOXED_UNIT, - BOOL -> BOXED_BOOLEAN, - BYTE -> BOXED_BYTE, - SHORT -> BOXED_SHORT, - CHAR -> BOXED_CHAR, - INT -> BOXED_INT, - LONG -> BOXED_LONG, - FLOAT -> BOXED_FLOAT, - DOUBLE -> BOXED_DOUBLE - ) + UNIT -> classBTypeFromSymbol(requiredClass[java.lang.Void]), + BOOL -> classBTypeFromSymbol(BoxedBooleanClass), + BYTE -> classBTypeFromSymbol(BoxedByteClass), + SHORT -> classBTypeFromSymbol(BoxedShortClass), + CHAR -> classBTypeFromSymbol(BoxedCharacterClass), + INT -> classBTypeFromSymbol(BoxedIntClass), + LONG -> classBTypeFromSymbol(BoxedLongClass), + FLOAT -> classBTypeFromSymbol(BoxedFloatClass), + DOUBLE -> classBTypeFromSymbol(BoxedDoubleClass)) lazy val boxedClasses: Set[ClassBType] = boxedClassOfPrimitive.values.toSet @@ -82,7 +71,7 @@ class CoreBTypes[BTFS <: BTypesFromSymbols[_ <: Global]](val bTypes: BTFS) { */ lazy val boxResultType: Map[Symbol, ClassBType] = { for ((valueClassSym, boxMethodSym) <- currentRun.runDefinitions.boxMethod) - yield boxMethodSym -> boxedClassOfPrimitive(primitiveTypeMap(valueClassSym)) + yield boxMethodSym -> boxedClassOfPrimitive(primitiveTypeToBType(valueClassSym)) } /** @@ -90,96 +79,148 @@ class CoreBTypes[BTFS <: BTypesFromSymbols[_ <: Global]](val bTypes: BTFS) { * For example, the method symbol for `Byte.unbox()`) is mapped to the PrimitiveBType BYTE. */ lazy val unboxResultType: Map[Symbol, PrimitiveBType] = { for ((valueClassSym, unboxMethodSym) <- currentRun.runDefinitions.unboxMethod) - yield unboxMethodSym -> primitiveTypeMap(valueClassSym) + yield unboxMethodSym -> primitiveTypeToBType(valueClassSym) } /* * RT_NOTHING and RT_NULL exist at run-time only. They are the bytecode-level manifestation (in - * method signatures only) of what shows up as NothingClass resp. NullClass in Scala ASTs. + * method signatures only) of what shows up as NothingClass (scala.Nothing) resp. NullClass + * (scala.Null) in Scala ASTs. * * Therefore, when RT_NOTHING or RT_NULL are to be emitted, a mapping is needed: the internal * names of NothingClass and NullClass can't be emitted as-is. */ - lazy val RT_NOTHING : ClassBType = classBTypeFromSymbol(requiredClass[scala.runtime.Nothing$]) - lazy val RT_NULL : ClassBType = classBTypeFromSymbol(requiredClass[scala.runtime.Null$]) - - lazy val ObjectReference : ClassBType = classBTypeFromSymbol(ObjectClass) - lazy val objArrayReference : ArrayBType = ArrayBType(ObjectReference) - - lazy val StringReference : ClassBType = classBTypeFromSymbol(StringClass) - lazy val StringBuilderReference : ClassBType = classBTypeFromSymbol(StringBuilderClass) - lazy val ThrowableReference : ClassBType = classBTypeFromSymbol(ThrowableClass) - lazy val jlCloneableReference : ClassBType = classBTypeFromSymbol(JavaCloneableClass) // java/lang/Cloneable - lazy val jlNPEReference : ClassBType = classBTypeFromSymbol(NullPointerExceptionClass) // java/lang/NullPointerException - lazy val jioSerializableReference : ClassBType = classBTypeFromSymbol(JavaSerializableClass) // java/io/Serializable - lazy val scalaSerializableReference : ClassBType = classBTypeFromSymbol(SerializableClass) // scala/Serializable - lazy val classCastExceptionReference : ClassBType = classBTypeFromSymbol(ClassCastExceptionClass) // java/lang/ClassCastException - lazy val javaUtilMapReference : ClassBType = classBTypeFromSymbol(JavaUtilMap) // java/util/Map - lazy val javaUtilHashMapReference : ClassBType = classBTypeFromSymbol(JavaUtilHashMap) // java/util/HashMap - - lazy val srBooleanRef : ClassBType = classBTypeFromSymbol(requiredClass[scala.runtime.BooleanRef]) - lazy val srByteRef : ClassBType = classBTypeFromSymbol(requiredClass[scala.runtime.ByteRef]) - lazy val srCharRef : ClassBType = classBTypeFromSymbol(requiredClass[scala.runtime.CharRef]) - lazy val srIntRef : ClassBType = classBTypeFromSymbol(requiredClass[scala.runtime.IntRef]) - lazy val srLongRef : ClassBType = classBTypeFromSymbol(requiredClass[scala.runtime.LongRef]) - lazy val srFloatRef : ClassBType = classBTypeFromSymbol(requiredClass[scala.runtime.FloatRef]) - lazy val srDoubleRef : ClassBType = classBTypeFromSymbol(requiredClass[scala.runtime.DoubleRef]) - - lazy val hashMethodSym: Symbol = getMember(ScalaRunTimeModule, nme.hash_) + lazy val srNothingRef : ClassBType = classBTypeFromSymbol(requiredClass[scala.runtime.Nothing$]) + lazy val srNullRef : ClassBType = classBTypeFromSymbol(requiredClass[scala.runtime.Null$]) + + lazy val ObjectRef : ClassBType = classBTypeFromSymbol(ObjectClass) + lazy val StringRef : ClassBType = classBTypeFromSymbol(StringClass) + lazy val PredefRef : ClassBType = classBTypeFromSymbol(PredefModule.moduleClass) + lazy val jlStringBuilderRef : ClassBType = classBTypeFromSymbol(JavaStringBuilderClass) + lazy val jlStringBufferRef : ClassBType = classBTypeFromSymbol(JavaStringBufferClass) + lazy val jlCharSequenceRef : ClassBType = classBTypeFromSymbol(JavaCharSequenceClass) + lazy val jlThrowableRef : ClassBType = classBTypeFromSymbol(ThrowableClass) + lazy val jlCloneableRef : ClassBType = classBTypeFromSymbol(JavaCloneableClass) // java/lang/Cloneable + lazy val jiSerializableRef : ClassBType = classBTypeFromSymbol(JavaSerializableClass) // java/io/Serializable + lazy val jlClassCastExceptionRef : ClassBType = classBTypeFromSymbol(ClassCastExceptionClass) // java/lang/ClassCastException + lazy val juMapRef : ClassBType = classBTypeFromSymbol(JavaUtilMap) // java/util/Map + lazy val juHashMapRef : ClassBType = classBTypeFromSymbol(JavaUtilHashMap) // java/util/HashMap + lazy val sbScalaBeanInfoRef : ClassBType = classBTypeFromSymbol(requiredClass[scala.beans.ScalaBeanInfo]) + lazy val jliSerializedLambdaRef : ClassBType = classBTypeFromSymbol(requiredClass[java.lang.invoke.SerializedLambda]) + lazy val jliMethodHandleRef : ClassBType = classBTypeFromSymbol(requiredClass[java.lang.invoke.MethodHandle]) + lazy val jliMethodHandlesRef : ClassBType = classBTypeFromSymbol(requiredClass[java.lang.invoke.MethodHandles]) + lazy val jliMethodHandlesLookupRef : ClassBType = classBTypeFromSymbol(exitingPickler(getRequiredClass("java.lang.invoke.MethodHandles.Lookup"))) // didn't find a reliable non-stringly-typed way that works for inner classes in the backend + lazy val jliMethodTypeRef : ClassBType = classBTypeFromSymbol(requiredClass[java.lang.invoke.MethodType]) + lazy val jliCallSiteRef : ClassBType = classBTypeFromSymbol(requiredClass[java.lang.invoke.CallSite]) + lazy val jliLambdaMetafactoryRef : ClassBType = classBTypeFromSymbol(requiredClass[java.lang.invoke.LambdaMetafactory]) + lazy val srBoxesRunTimeRef : ClassBType = classBTypeFromSymbol(requiredClass[scala.runtime.BoxesRunTime]) + lazy val srSymbolLiteral : ClassBType = classBTypeFromSymbol(requiredClass[scala.runtime.SymbolLiteral]) + lazy val srStructuralCallSite : ClassBType = classBTypeFromSymbol(requiredClass[scala.runtime.StructuralCallSite]) + lazy val srLambdaDeserialize : ClassBType = classBTypeFromSymbol(requiredClass[scala.runtime.LambdaDeserialize]) + lazy val srBoxedUnitRef : ClassBType = classBTypeFromSymbol(requiredClass[scala.runtime.BoxedUnit]) + + private def methodNameAndType(cls: Symbol, name: Name, static: Boolean = false, filterOverload: Symbol => Boolean = _ => true): MethodNameAndType = { + val holder = if (static) cls.companionModule.moduleClass else cls + val method = holder.info.member(name).suchThat(filterOverload) + assert(!method.isOverloaded, method) + MethodNameAndType(name.toString, methodBTypeFromSymbol(method)) + } - // TODO @lry avoiding going through through missingHook for every line in the REPL: https://github.com/scala/scala/commit/8d962ed4ddd310cc784121c426a2e3f56a112540 - lazy val AndroidParcelableInterface : Symbol = getClassIfDefined("android.os.Parcelable") - lazy val AndroidCreatorClass : Symbol = getClassIfDefined("android.os.Parcelable$Creator") + private def srBoxesRuntimeMethods(getName: (String, String) => String): Map[BType, MethodNameAndType] = { + ScalaValueClassesNoUnit.map(primitive => { + val bType = primitiveTypeToBType(primitive) + val name = newTermName(getName(primitive.name.toString, boxedClass(primitive).name.toString)) + (bType, methodNameAndType(BoxesRunTimeClass, name)) + })(collection.breakOut) + } - lazy val BeanInfoAttr: Symbol = requiredClass[scala.beans.BeanInfo] + // Z -> MethodNameAndType(boxToBoolean,(Z)Ljava/lang/Boolean;) + lazy val srBoxesRuntimeBoxToMethods: Map[BType, MethodNameAndType] = srBoxesRuntimeMethods((primitive, boxed) => "boxTo" + boxed) - /* The Object => String overload. */ - lazy val String_valueOf: Symbol = { - getMember(StringModule, nme.valueOf) filter (sym => sym.info.paramTypes match { - case List(pt) => pt.typeSymbol == ObjectClass - case _ => false - }) + // Z -> MethodNameAndType(unboxToBoolean,(Ljava/lang/Object;)Z) + lazy val srBoxesRuntimeUnboxToMethods: Map[BType, MethodNameAndType] = srBoxesRuntimeMethods((primitive, boxed) => "unboxTo" + primitive) + + def singleParamOfClass(cls: Symbol) = (s: Symbol) => s.paramss match { + case List(List(param)) => param.info.typeSymbol == cls + case _ => false } - // scala.FunctionX and scala.runtim.AbstractFunctionX - lazy val FunctionReference : Vector[ClassBType] = (0 to MaxFunctionArity).map(i => classBTypeFromSymbol(FunctionClass(i)))(collection.breakOut) - lazy val AbstractFunctionReference : Vector[ClassBType] = (0 to MaxFunctionArity).map(i => classBTypeFromSymbol(AbstractFunctionClass(i)))(collection.breakOut) - lazy val AbstractFunctionArityMap : Map[ClassBType, Int] = AbstractFunctionReference.zipWithIndex.toMap + // java/lang/Boolean -> MethodNameAndType(valueOf,(Z)Ljava/lang/Boolean;) + lazy val javaBoxMethods: Map[InternalName, MethodNameAndType] = { + ScalaValueClassesNoUnit.map(primitive => { + val boxed = boxedClass(primitive) + val method = methodNameAndType(boxed, newTermName("valueOf"), static = true, filterOverload = singleParamOfClass(primitive)) + (classBTypeFromSymbol(boxed).internalName, method) + })(collection.breakOut) + } - lazy val PartialFunctionReference : ClassBType = classBTypeFromSymbol(PartialFunctionClass) - lazy val AbstractPartialFunctionReference : ClassBType = classBTypeFromSymbol(AbstractPartialFunctionClass) + // java/lang/Boolean -> MethodNameAndType(booleanValue,()Z) + lazy val javaUnboxMethods: Map[InternalName, MethodNameAndType] = { + ScalaValueClassesNoUnit.map(primitive => { + val boxed = boxedClass(primitive) + val name = primitive.name.toString.toLowerCase + "Value" + (classBTypeFromSymbol(boxed).internalName, methodNameAndType(boxed, newTermName(name))) + })(collection.breakOut) + } - lazy val BoxesRunTime: ClassBType = classBTypeFromSymbol(requiredClass[scala.runtime.BoxesRunTime]) + private def predefBoxingMethods(getName: (String, String) => String): Map[String, MethodBType] = { + ScalaValueClassesNoUnit.map(primitive => { + val boxed = boxedClass(primitive) + val name = getName(primitive.name.toString, boxed.name.toString) + (name, methodNameAndType(PredefModule.moduleClass, newTermName(name)).methodType) + })(collection.breakOut) + } - /** - * Methods in scala.runtime.BoxesRuntime - */ - lazy val asmBoxTo : Map[BType, MethodNameAndType] = Map( - BOOL -> MethodNameAndType("boxToBoolean", MethodBType(List(BOOL), BOXED_BOOLEAN)), - BYTE -> MethodNameAndType("boxToByte", MethodBType(List(BYTE), BOXED_BYTE)), - CHAR -> MethodNameAndType("boxToCharacter", MethodBType(List(CHAR), BOXED_CHAR)), - SHORT -> MethodNameAndType("boxToShort", MethodBType(List(SHORT), BOXED_SHORT)), - INT -> MethodNameAndType("boxToInteger", MethodBType(List(INT), BOXED_INT)), - LONG -> MethodNameAndType("boxToLong", MethodBType(List(LONG), BOXED_LONG)), - FLOAT -> MethodNameAndType("boxToFloat", MethodBType(List(FLOAT), BOXED_FLOAT)), - DOUBLE -> MethodNameAndType("boxToDouble", MethodBType(List(DOUBLE), BOXED_DOUBLE)) - ) - - lazy val asmUnboxTo: Map[BType, MethodNameAndType] = Map( - BOOL -> MethodNameAndType("unboxToBoolean", MethodBType(List(ObjectReference), BOOL)), - BYTE -> MethodNameAndType("unboxToByte", MethodBType(List(ObjectReference), BYTE)), - CHAR -> MethodNameAndType("unboxToChar", MethodBType(List(ObjectReference), CHAR)), - SHORT -> MethodNameAndType("unboxToShort", MethodBType(List(ObjectReference), SHORT)), - INT -> MethodNameAndType("unboxToInt", MethodBType(List(ObjectReference), INT)), - LONG -> MethodNameAndType("unboxToLong", MethodBType(List(ObjectReference), LONG)), - FLOAT -> MethodNameAndType("unboxToFloat", MethodBType(List(ObjectReference), FLOAT)), - DOUBLE -> MethodNameAndType("unboxToDouble", MethodBType(List(ObjectReference), DOUBLE)) - ) + // boolean2Boolean -> (Z)Ljava/lang/Boolean; + lazy val predefAutoBoxMethods: Map[String, MethodBType] = predefBoxingMethods((primitive, boxed) => primitive.toLowerCase + "2" + boxed) + + // Boolean2boolean -> (Ljava/lang/Boolean;)Z + lazy val predefAutoUnboxMethods: Map[String, MethodBType] = predefBoxingMethods((primitive, boxed) => boxed + "2" + primitive.toLowerCase) + + private def staticRefMethods(name: Name): Map[InternalName, MethodNameAndType] = { + allRefClasses.map(refClass => + (classBTypeFromSymbol(refClass).internalName, methodNameAndType(refClass, name, static = true)))(collection.breakOut) + } + + // scala/runtime/BooleanRef -> MethodNameAndType(create,(Z)Lscala/runtime/BooleanRef;) + lazy val srRefCreateMethods: Map[InternalName, MethodNameAndType] = staticRefMethods(nme.create) + + // scala/runtime/BooleanRef -> MethodNameAndType(zero,()Lscala/runtime/BooleanRef;) + lazy val srRefZeroMethods: Map[InternalName, MethodNameAndType] = staticRefMethods(nme.zero) + + // java/lang/Boolean -> MethodNameAndType(<init>,(Z)V) + lazy val primitiveBoxConstructors: Map[InternalName, MethodNameAndType] = { + ScalaValueClassesNoUnit.map(primitive => { + val boxed = boxedClass(primitive) + (classBTypeFromSymbol(boxed).internalName, methodNameAndType(boxed, nme.CONSTRUCTOR, filterOverload = singleParamOfClass(primitive))) + })(collection.breakOut) + } + + private def nonOverloadedConstructors(classes: Iterable[Symbol]): Map[InternalName, MethodNameAndType] = { + classes.map(cls => (classBTypeFromSymbol(cls).internalName, methodNameAndType(cls, nme.CONSTRUCTOR)))(collection.breakOut) + } + + // scala/runtime/BooleanRef -> MethodNameAndType(<init>,(Z)V) + lazy val srRefConstructors: Map[InternalName, MethodNameAndType] = nonOverloadedConstructors(allRefClasses) + + private def specializedSubclasses(cls: Symbol): List[Symbol] = { + exitingSpecialize(cls.info) // the `transformInfo` method of specialization adds specialized subclasses to the `specializedClass` map + specializeTypes.specializedClass.collect({ + case ((`cls`, _), specCls) => specCls + }).toList + } + + // scala/Tuple3 -> MethodNameAndType(<init>,(Ljava/lang/Object;Ljava/lang/Object;Ljava/lang/Object;)V) + // scala/Tuple2$mcZC$sp -> MethodNameAndType(<init>,(ZC)V) + lazy val tupleClassConstructors: Map[InternalName, MethodNameAndType] = { + val tupleClassSymbols = TupleClass.seq ++ specializedSubclasses(TupleClass(1)) ++ specializedSubclasses(TupleClass(2)) + nonOverloadedConstructors(tupleClassSymbols) + } lazy val typeOfArrayOp: Map[Int, BType] = { import scalaPrimitives._ Map( - (List(ZARRAY_LENGTH, ZARRAY_GET, ZARRAY_SET) map (_ -> BOOL)) ++ + (List(ZARRAY_LENGTH, ZARRAY_GET, ZARRAY_SET) map (_ -> BOOL)) ++ (List(BARRAY_LENGTH, BARRAY_GET, BARRAY_SET) map (_ -> BYTE)) ++ (List(SARRAY_LENGTH, SARRAY_GET, SARRAY_SET) map (_ -> SHORT)) ++ (List(CARRAY_LENGTH, CARRAY_GET, CARRAY_SET) map (_ -> CHAR)) ++ @@ -187,9 +228,67 @@ class CoreBTypes[BTFS <: BTypesFromSymbols[_ <: Global]](val bTypes: BTFS) { (List(LARRAY_LENGTH, LARRAY_GET, LARRAY_SET) map (_ -> LONG)) ++ (List(FARRAY_LENGTH, FARRAY_GET, FARRAY_SET) map (_ -> FLOAT)) ++ (List(DARRAY_LENGTH, DARRAY_GET, DARRAY_SET) map (_ -> DOUBLE)) ++ - (List(OARRAY_LENGTH, OARRAY_GET, OARRAY_SET) map (_ -> ObjectReference)) : _* + (List(OARRAY_LENGTH, OARRAY_GET, OARRAY_SET) map (_ -> ObjectRef)) : _* ) } + + lazy val hashMethodSym: Symbol = getMember(RuntimeStaticsModule, nme.anyHash) + + // TODO @lry avoiding going through through missingHook for every line in the REPL: https://github.com/scala/scala/commit/8d962ed4ddd310cc784121c426a2e3f56a112540 + lazy val AndroidParcelableInterface : Symbol = getClassIfDefined("android.os.Parcelable") + lazy val AndroidCreatorClass : Symbol = getClassIfDefined("android.os.Parcelable$Creator") + + lazy val BeanInfoAttr: Symbol = requiredClass[scala.beans.BeanInfo] + + /* The Object => String overload. */ + lazy val String_valueOf: Symbol = { + getMember(StringModule, nme.valueOf) filter (sym => sym.info.paramTypes match { + case List(pt) => pt.typeSymbol == ObjectClass + case _ => false + }) + } + + lazy val lambdaMetaFactoryMetafactoryHandle = + new asm.Handle(asm.Opcodes.H_INVOKESTATIC, + coreBTypes.jliLambdaMetafactoryRef.internalName, sn.Metafactory.toString, + MethodBType( + List( + coreBTypes.jliMethodHandlesLookupRef, + coreBTypes.StringRef, + coreBTypes.jliMethodTypeRef, + coreBTypes.jliMethodTypeRef, + coreBTypes.jliMethodHandleRef, + coreBTypes.jliMethodTypeRef), + coreBTypes.jliCallSiteRef + ).descriptor, + /* itf = */ coreBTypes.jliLambdaMetafactoryRef.isInterface.get) + + lazy val lambdaMetaFactoryAltMetafactoryHandle = + new asm.Handle(asm.Opcodes.H_INVOKESTATIC, + coreBTypes.jliLambdaMetafactoryRef.internalName, sn.AltMetafactory.toString, + MethodBType( + List( + coreBTypes.jliMethodHandlesLookupRef, + coreBTypes.StringRef, + coreBTypes.jliMethodTypeRef, + ArrayBType(ObjectRef)), + coreBTypes.jliCallSiteRef + ).descriptor, + /* itf = */ coreBTypes.jliLambdaMetafactoryRef.isInterface.get) + + lazy val lambdaDeserializeBootstrapHandle = + new scala.tools.asm.Handle(scala.tools.asm.Opcodes.H_INVOKESTATIC, + coreBTypes.srLambdaDeserialize.internalName, sn.Bootstrap.toString, + MethodBType( + List( + coreBTypes.jliMethodHandlesLookupRef, + coreBTypes.StringRef, + coreBTypes.jliMethodTypeRef, + ArrayBType(jliMethodHandleRef) + ), + coreBTypes.jliCallSiteRef + ).descriptor, + /* itf = */ coreBTypes.srLambdaDeserialize.isInterface.get) } /** @@ -205,13 +304,46 @@ trait CoreBTypesProxyGlobalIndependent[BTS <: BTypes] { import bTypes._ def boxedClasses: Set[ClassBType] - - def RT_NOTHING : ClassBType - def RT_NULL : ClassBType - - def ObjectReference : ClassBType - def jlCloneableReference : ClassBType - def jioSerializableReference : ClassBType + def boxedClassOfPrimitive: Map[PrimitiveBType, ClassBType] + + def srNothingRef : ClassBType + def srNullRef : ClassBType + + def ObjectRef : ClassBType + def StringRef : ClassBType + def PredefRef : ClassBType + def jlCloneableRef : ClassBType + def jiSerializableRef : ClassBType + def juHashMapRef : ClassBType + def juMapRef : ClassBType + def jliCallSiteRef : ClassBType + def jliLambdaMetafactoryRef : ClassBType + def jliMethodTypeRef : ClassBType + def jliSerializedLambdaRef : ClassBType + def jliMethodHandleRef : ClassBType + def jliMethodHandlesLookupRef : ClassBType + def srBoxesRunTimeRef : ClassBType + def srBoxedUnitRef : ClassBType + + def srBoxesRuntimeBoxToMethods : Map[BType, MethodNameAndType] + def srBoxesRuntimeUnboxToMethods : Map[BType, MethodNameAndType] + + def javaBoxMethods : Map[InternalName, MethodNameAndType] + def javaUnboxMethods : Map[InternalName, MethodNameAndType] + + def predefAutoBoxMethods : Map[String, MethodBType] + def predefAutoUnboxMethods : Map[String, MethodBType] + + def srRefCreateMethods : Map[InternalName, MethodNameAndType] + def srRefZeroMethods : Map[InternalName, MethodNameAndType] + + def primitiveBoxConstructors : Map[InternalName, MethodNameAndType] + def srRefConstructors : Map[InternalName, MethodNameAndType] + def tupleClassConstructors : Map[InternalName, MethodNameAndType] + + def lambdaMetaFactoryMetafactoryHandle : asm.Handle + def lambdaMetaFactoryAltMetafactoryHandle : asm.Handle + def lambdaDeserializeBootstrapHandle : asm.Handle } /** @@ -226,50 +358,63 @@ final class CoreBTypesProxy[BTFS <: BTypesFromSymbols[_ <: Global]](val bTypes: _coreBTypes = coreBTypes.asInstanceOf[CoreBTypes[bTypes.type]] } - def primitiveTypeMap: Map[Symbol, PrimitiveBType] = _coreBTypes.primitiveTypeMap - - def BOXED_UNIT : ClassBType = _coreBTypes.BOXED_UNIT - def BOXED_BOOLEAN : ClassBType = _coreBTypes.BOXED_BOOLEAN - def BOXED_BYTE : ClassBType = _coreBTypes.BOXED_BYTE - def BOXED_SHORT : ClassBType = _coreBTypes.BOXED_SHORT - def BOXED_CHAR : ClassBType = _coreBTypes.BOXED_CHAR - def BOXED_INT : ClassBType = _coreBTypes.BOXED_INT - def BOXED_LONG : ClassBType = _coreBTypes.BOXED_LONG - def BOXED_FLOAT : ClassBType = _coreBTypes.BOXED_FLOAT - def BOXED_DOUBLE : ClassBType = _coreBTypes.BOXED_DOUBLE + def primitiveTypeToBType: Map[Symbol, PrimitiveBType] = _coreBTypes.primitiveTypeToBType def boxedClasses: Set[ClassBType] = _coreBTypes.boxedClasses - def boxedClassOfPrimitive: Map[PrimitiveBType, ClassBType] = _coreBTypes.boxedClassOfPrimitive def boxResultType: Map[Symbol, ClassBType] = _coreBTypes.boxResultType - def unboxResultType: Map[Symbol, PrimitiveBType] = _coreBTypes.unboxResultType - def RT_NOTHING : ClassBType = _coreBTypes.RT_NOTHING - def RT_NULL : ClassBType = _coreBTypes.RT_NULL - - def ObjectReference : ClassBType = _coreBTypes.ObjectReference - def objArrayReference : ArrayBType = _coreBTypes.objArrayReference - - def StringReference : ClassBType = _coreBTypes.StringReference - def StringBuilderReference : ClassBType = _coreBTypes.StringBuilderReference - def ThrowableReference : ClassBType = _coreBTypes.ThrowableReference - def jlCloneableReference : ClassBType = _coreBTypes.jlCloneableReference - def jlNPEReference : ClassBType = _coreBTypes.jlNPEReference - def jioSerializableReference : ClassBType = _coreBTypes.jioSerializableReference - def scalaSerializableReference : ClassBType = _coreBTypes.scalaSerializableReference - def classCastExceptionReference : ClassBType = _coreBTypes.classCastExceptionReference - def javaUtilMapReference : ClassBType = _coreBTypes.javaUtilMapReference - def javaUtilHashMapReference : ClassBType = _coreBTypes.javaUtilHashMapReference - - def srBooleanRef : ClassBType = _coreBTypes.srBooleanRef - def srByteRef : ClassBType = _coreBTypes.srByteRef - def srCharRef : ClassBType = _coreBTypes.srCharRef - def srIntRef : ClassBType = _coreBTypes.srIntRef - def srLongRef : ClassBType = _coreBTypes.srLongRef - def srFloatRef : ClassBType = _coreBTypes.srFloatRef - def srDoubleRef : ClassBType = _coreBTypes.srDoubleRef + def srNothingRef : ClassBType = _coreBTypes.srNothingRef + def srNullRef : ClassBType = _coreBTypes.srNullRef + + def ObjectRef : ClassBType = _coreBTypes.ObjectRef + def StringRef : ClassBType = _coreBTypes.StringRef + def PredefRef : ClassBType = _coreBTypes.PredefRef + def jlStringBuilderRef : ClassBType = _coreBTypes.jlStringBuilderRef + def jlStringBufferRef : ClassBType = _coreBTypes.jlStringBufferRef + def jlCharSequenceRef : ClassBType = _coreBTypes.jlCharSequenceRef + def jlThrowableRef : ClassBType = _coreBTypes.jlThrowableRef + def jlCloneableRef : ClassBType = _coreBTypes.jlCloneableRef + def jiSerializableRef : ClassBType = _coreBTypes.jiSerializableRef + def jlClassCastExceptionRef : ClassBType = _coreBTypes.jlClassCastExceptionRef + def juMapRef : ClassBType = _coreBTypes.juMapRef + def juHashMapRef : ClassBType = _coreBTypes.juHashMapRef + def sbScalaBeanInfoRef : ClassBType = _coreBTypes.sbScalaBeanInfoRef + def jliSerializedLambdaRef : ClassBType = _coreBTypes.jliSerializedLambdaRef + def jliMethodHandleRef : ClassBType = _coreBTypes.jliMethodHandleRef + def jliMethodHandlesRef : ClassBType = _coreBTypes.jliMethodHandlesRef + def jliMethodHandlesLookupRef : ClassBType = _coreBTypes.jliMethodHandlesLookupRef + def jliMethodTypeRef : ClassBType = _coreBTypes.jliMethodTypeRef + def jliCallSiteRef : ClassBType = _coreBTypes.jliCallSiteRef + def jliLambdaMetafactoryRef : ClassBType = _coreBTypes.jliLambdaMetafactoryRef + def srBoxesRunTimeRef : ClassBType = _coreBTypes.srBoxesRunTimeRef + def srBoxedUnitRef : ClassBType = _coreBTypes.srBoxedUnitRef + + def srBoxesRuntimeBoxToMethods : Map[BType, MethodNameAndType] = _coreBTypes.srBoxesRuntimeBoxToMethods + def srBoxesRuntimeUnboxToMethods : Map[BType, MethodNameAndType] = _coreBTypes.srBoxesRuntimeUnboxToMethods + + def javaBoxMethods : Map[InternalName, MethodNameAndType] = _coreBTypes.javaBoxMethods + def javaUnboxMethods : Map[InternalName, MethodNameAndType] = _coreBTypes.javaUnboxMethods + + def predefAutoBoxMethods : Map[String, MethodBType] = _coreBTypes.predefAutoBoxMethods + def predefAutoUnboxMethods : Map[String, MethodBType] = _coreBTypes.predefAutoUnboxMethods + + def srRefCreateMethods : Map[InternalName, MethodNameAndType] = _coreBTypes.srRefCreateMethods + def srRefZeroMethods : Map[InternalName, MethodNameAndType] = _coreBTypes.srRefZeroMethods + + def primitiveBoxConstructors : Map[InternalName, MethodNameAndType] = _coreBTypes.primitiveBoxConstructors + def srRefConstructors : Map[InternalName, MethodNameAndType] = _coreBTypes.srRefConstructors + def tupleClassConstructors : Map[InternalName, MethodNameAndType] = _coreBTypes.tupleClassConstructors + + def srSymbolLiteral : ClassBType = _coreBTypes.srSymbolLiteral + def srStructuralCallSite : ClassBType = _coreBTypes.srStructuralCallSite + def srLambdaDeserialize : ClassBType = _coreBTypes.srLambdaDeserialize + + def typeOfArrayOp: Map[Int, BType] = _coreBTypes.typeOfArrayOp + + // Some symbols. These references should probably be moved to Definitions. def hashMethodSym: Symbol = _coreBTypes.hashMethodSym @@ -280,17 +425,7 @@ final class CoreBTypesProxy[BTFS <: BTypesFromSymbols[_ <: Global]](val bTypes: def String_valueOf: Symbol = _coreBTypes.String_valueOf - def FunctionReference : Vector[ClassBType] = _coreBTypes.FunctionReference - def AbstractFunctionReference : Vector[ClassBType] = _coreBTypes.AbstractFunctionReference - def AbstractFunctionArityMap : Map[ClassBType, Int] = _coreBTypes.AbstractFunctionArityMap - - def PartialFunctionReference : ClassBType = _coreBTypes.PartialFunctionReference - def AbstractPartialFunctionReference : ClassBType = _coreBTypes.AbstractPartialFunctionReference - - def BoxesRunTime: ClassBType = _coreBTypes.BoxesRunTime - - def asmBoxTo : Map[BType, MethodNameAndType] = _coreBTypes.asmBoxTo - def asmUnboxTo: Map[BType, MethodNameAndType] = _coreBTypes.asmUnboxTo - - def typeOfArrayOp: Map[Int, BType] = _coreBTypes.typeOfArrayOp + def lambdaMetaFactoryMetafactoryHandle : asm.Handle = _coreBTypes.lambdaMetaFactoryMetafactoryHandle + def lambdaMetaFactoryAltMetafactoryHandle : asm.Handle = _coreBTypes.lambdaMetaFactoryAltMetafactoryHandle + def lambdaDeserializeBootstrapHandle : asm.Handle = _coreBTypes.lambdaDeserializeBootstrapHandle } diff --git a/src/compiler/scala/tools/nsc/backend/jvm/GenASM.scala b/src/compiler/scala/tools/nsc/backend/jvm/GenASM.scala deleted file mode 100644 index 4768417c67..0000000000 --- a/src/compiler/scala/tools/nsc/backend/jvm/GenASM.scala +++ /dev/null @@ -1,3350 +0,0 @@ -/* NSC -- new Scala compiler - * Copyright 2005-2013 LAMP/EPFL - * @author Martin Odersky - */ - -package scala -package tools.nsc -package backend.jvm - -import scala.collection.{ mutable, immutable } -import scala.reflect.internal.pickling.{ PickleFormat, PickleBuffer } -import scala.tools.nsc.backend.jvm.opt.InlineInfoAttribute -import scala.tools.nsc.symtab._ -import scala.tools.asm -import asm.Label -import scala.annotation.tailrec - -/** - * @author Iulian Dragos (version 1.0, FJBG-based implementation) - * @author Miguel Garcia (version 2.0, ASM-based implementation) - * - * Documentation at http://lamp.epfl.ch/~magarcia/ScalaCompilerCornerReloaded/2012Q2/GenASM.pdf - */ -abstract class GenASM extends SubComponent with BytecodeWriters { self => - import global._ - import icodes._ - import icodes.opcodes._ - import definitions._ - - val bCodeAsmCommon: BCodeAsmCommon[global.type] = new BCodeAsmCommon(global) - import bCodeAsmCommon._ - - // Strangely I can't find this in the asm code - // 255, but reserving 1 for "this" - final val MaximumJvmParameters = 254 - - val phaseName = "jvm" - - /** Create a new phase */ - override def newPhase(p: Phase): Phase = new AsmPhase(p) - - /** From the reference documentation of the Android SDK: - * The `Parcelable` interface identifies classes whose instances can be written to and restored from a `Parcel`. - * Classes implementing the `Parcelable` interface must also have a static field called `CREATOR`, - * which is an object implementing the `Parcelable.Creator` interface. - */ - private val androidFieldName = newTermName("CREATOR") - - private lazy val AndroidParcelableInterface = rootMirror.getClassIfDefined("android.os.Parcelable") - private lazy val AndroidCreatorClass = rootMirror.getClassIfDefined("android.os.Parcelable$Creator") - - /** JVM code generation phase - */ - class AsmPhase(prev: Phase) extends ICodePhase(prev) { - def name = phaseName - override def erasedTypes = true - def apply(cls: IClass) = sys.error("no implementation") - - // An AsmPhase starts and ends within a Run, thus the caches in question will get populated and cleared within a Run, too), SI-7422 - javaNameCache.clear() - javaNameCache ++= List( - NothingClass -> binarynme.RuntimeNothing, - RuntimeNothingClass -> binarynme.RuntimeNothing, - NullClass -> binarynme.RuntimeNull, - RuntimeNullClass -> binarynme.RuntimeNull - ) - - // unlike javaNameCache, reverseJavaName contains entries only for class symbols and their internal names. - reverseJavaName.clear() - reverseJavaName ++= List( - binarynme.RuntimeNothing.toString() -> RuntimeNothingClass, // RuntimeNothingClass is the bytecode-level return type of Scala methods with Nothing return-type. - binarynme.RuntimeNull.toString() -> RuntimeNullClass - ) - - // Lazy val; can't have eager vals in Phase constructors which may - // cause cycles before Global has finished initialization. - lazy val BeanInfoAttr = rootMirror.getRequiredClass("scala.beans.BeanInfo") - - private def initBytecodeWriter(entryPoints: List[IClass]): BytecodeWriter = { - settings.outputDirs.getSingleOutput match { - case Some(f) if f hasExtension "jar" => - // If no main class was specified, see if there's only one - // entry point among the classes going into the jar. - if (settings.mainClass.isDefault) { - entryPoints map (_.symbol fullName '.') match { - case Nil => - log("No Main-Class designated or discovered.") - case name :: Nil => - log("Unique entry point: setting Main-Class to " + name) - settings.mainClass.value = name - case names => - log("No Main-Class due to multiple entry points:\n " + names.mkString("\n ")) - } - } - else log("Main-Class was specified: " + settings.mainClass.value) - - new DirectToJarfileWriter(f.file) - - case _ => factoryNonJarBytecodeWriter() - } - } - - private def isJavaEntryPoint(icls: IClass) = { - val sym = icls.symbol - def fail(msg: String, pos: Position = sym.pos) = { - reporter.warning(sym.pos, - sym.name + " has a main method with parameter type Array[String], but " + sym.fullName('.') + " will not be a runnable program.\n" + - " Reason: " + msg - // TODO: make this next claim true, if possible - // by generating valid main methods as static in module classes - // not sure what the jvm allows here - // + " You can still run the program by calling it as " + sym.javaSimpleName + " instead." - ) - false - } - def failNoForwarder(msg: String) = { - fail(msg + ", which means no static forwarder can be generated.\n") - } - val possibles = if (sym.hasModuleFlag) (sym.tpe nonPrivateMember nme.main).alternatives else Nil - val hasApproximate = possibles exists { m => - m.info match { - case MethodType(p :: Nil, _) => p.tpe.typeSymbol == ArrayClass - case _ => false - } - } - // At this point it's a module with a main-looking method, so either succeed or warn that it isn't. - hasApproximate && { - // Before erasure so we can identify generic mains. - enteringErasure { - val companion = sym.linkedClassOfClass - - if (hasJavaMainMethod(companion)) - failNoForwarder("companion contains its own main method") - else if (companion.tpe.member(nme.main) != NoSymbol) - // this is only because forwarders aren't smart enough yet - failNoForwarder("companion contains its own main method (implementation restriction: no main is allowed, regardless of signature)") - else if (companion.isTrait) - failNoForwarder("companion is a trait") - // Now either succeeed, or issue some additional warnings for things which look like - // attempts to be java main methods. - else (possibles exists isJavaMainMethod) || { - possibles exists { m => - m.info match { - case PolyType(_, _) => - fail("main methods cannot be generic.") - case MethodType(params, res) => - if (res.typeSymbol :: params exists (_.isAbstractType)) - fail("main methods cannot refer to type parameters or abstract types.", m.pos) - else - isJavaMainMethod(m) || fail("main method must have exact signature (Array[String])Unit", m.pos) - case tp => - fail("don't know what this is: " + tp, m.pos) - } - } - } - } - } - } - - override def run() { - - if (settings.debug) - inform("[running phase " + name + " on icode]") - - if (settings.Xdce) { - val classes = icodes.classes.keys.toList // copy to avoid mutating the map while iterating - for (sym <- classes if inliner.isClosureClass(sym) && !deadCode.liveClosures(sym)) { - log(s"Optimizer eliminated ${sym.fullNameString}") - deadCode.elidedClosures += sym - icodes.classes -= sym - } - } - - // For predictably ordered error messages. - var sortedClasses = classes.values.toList sortBy (_.symbol.fullName) - - // Warn when classes will overwrite one another on case-insensitive systems. - for ((_, v1 :: v2 :: _) <- sortedClasses groupBy (_.symbol.javaClassName.toString.toLowerCase)) { - reporter.warning(v1.symbol.pos, - s"Class ${v1.symbol.javaClassName} differs only in case from ${v2.symbol.javaClassName}. " + - "Such classes will overwrite one another on case-insensitive filesystems.") - } - - debuglog(s"Created new bytecode generator for ${classes.size} classes.") - val bytecodeWriter = initBytecodeWriter(sortedClasses filter isJavaEntryPoint) - val needsOutfile = bytecodeWriter.isInstanceOf[ClassBytecodeWriter] - val plainCodeGen = new JPlainBuilder( bytecodeWriter, needsOutfile) - val mirrorCodeGen = new JMirrorBuilder( bytecodeWriter, needsOutfile) - val beanInfoCodeGen = new JBeanInfoBuilder(bytecodeWriter, needsOutfile) - - def emitFor(c: IClass) { - if (isStaticModule(c.symbol) && isTopLevelModule(c.symbol)) { - if (c.symbol.companionClass == NoSymbol) - mirrorCodeGen genMirrorClass (c.symbol, c.cunit) - else - log(s"No mirror class for module with linked class: ${c.symbol.fullName}") - } - plainCodeGen genClass c - if (c.symbol hasAnnotation BeanInfoAttr) beanInfoCodeGen genBeanInfoClass c - } - - while (!sortedClasses.isEmpty) { - val c = sortedClasses.head - try emitFor(c) - catch { - case e: FileConflictException => - reporter.error(c.symbol.pos, s"error writing ${c.symbol}: ${e.getMessage}") - } - sortedClasses = sortedClasses.tail - classes -= c.symbol // GC opportunity - } - - bytecodeWriter.close() - - /* don't javaNameCache.clear() because that causes the following tests to fail: - * test/files/run/macro-repl-dontexpand.scala - * test/files/jvm/interpreter.scala - * TODO but why? what use could javaNameCache possibly see once GenASM is over? - */ - - /* TODO After emitting all class files (e.g., in a separate compiler phase) ASM can perform bytecode verification: - * - * (1) call the asm.util.CheckAdapter.verify() overload: - * public static void verify(ClassReader cr, ClassLoader loader, boolean dump, PrintWriter pw) - * - * (2) passing a custom ClassLoader to verify inter-dependent classes. - * - * Alternatively, an offline-bytecode verifier could be used (e.g. Maxine brings one as separate tool). - */ - - } // end of AsmPhase.run() - - } // end of class AsmPhase - - var pickledBytes = 0 // statistics - - val javaNameCache = perRunCaches.newAnyRefMap[Symbol, Name]() - - // unlike javaNameCache, reverseJavaName contains entries only for class symbols and their internal names. - val reverseJavaName = perRunCaches.newAnyRefMap[String, Symbol]() - - private def mkFlags(args: Int*) = args.foldLeft(0)(_ | _) - private def hasPublicBitSet(flags: Int) = (flags & asm.Opcodes.ACC_PUBLIC) != 0 - private def isRemote(s: Symbol) = s hasAnnotation RemoteAttr - - /** - * Return the Java modifiers for the given symbol. - * Java modifiers for classes: - * - public, abstract, final, strictfp (not used) - * for interfaces: - * - the same as for classes, without 'final' - * for fields: - * - public, private (*) - * - static, final - * for methods: - * - the same as for fields, plus: - * - abstract, synchronized (not used), strictfp (not used), native (not used) - * - * (*) protected cannot be used, since inner classes 'see' protected members, - * and they would fail verification after lifted. - */ - def javaFlags(sym: Symbol): Int = { - // constructors of module classes should be private - // PP: why are they only being marked private at this stage and not earlier? - val privateFlag = - sym.isPrivate || (sym.isPrimaryConstructor && isTopLevelModule(sym.owner)) - - // Final: the only fields which can receive ACC_FINAL are eager vals. - // Neither vars nor lazy vals can, because: - // - // Source: http://docs.oracle.com/javase/specs/jls/se7/html/jls-17.html#jls-17.5.3 - // "Another problem is that the specification allows aggressive - // optimization of final fields. Within a thread, it is permissible to - // reorder reads of a final field with those modifications of a final - // field that do not take place in the constructor." - // - // A var or lazy val which is marked final still has meaning to the - // scala compiler. The word final is heavily overloaded unfortunately; - // for us it means "not overridable". At present you can't override - // vars regardless; this may change. - // - // The logic does not check .isFinal (which checks flags for the FINAL flag, - // and includes symbols marked lateFINAL) instead inspecting rawflags so - // we can exclude lateFINAL. Such symbols are eligible for inlining, but to - // avoid breaking proxy software which depends on subclassing, we do not - // emit ACC_FINAL. - // Nested objects won't receive ACC_FINAL in order to allow for their overriding. - - val finalFlag = ( - (((sym.rawflags & Flags.FINAL) != 0) || isTopLevelModule(sym)) - && !sym.enclClass.isInterface - && !sym.isClassConstructor - && !sym.isMutable // lazy vals and vars both - ) - - // Primitives are "abstract final" to prohibit instantiation - // without having to provide any implementations, but that is an - // illegal combination of modifiers at the bytecode level so - // suppress final if abstract if present. - import asm.Opcodes._ - mkFlags( - if (privateFlag) ACC_PRIVATE else ACC_PUBLIC, - if (sym.isDeferred || sym.hasAbstractFlag) ACC_ABSTRACT else 0, - if (sym.isInterface) ACC_INTERFACE else 0, - if (finalFlag && !sym.hasAbstractFlag) ACC_FINAL else 0, - if (sym.isStaticMember) ACC_STATIC else 0, - if (sym.isBridge) ACC_BRIDGE | ACC_SYNTHETIC else 0, - if (sym.isArtifact) ACC_SYNTHETIC else 0, - if (sym.isClass && !sym.isInterface) ACC_SUPER else 0, - if (sym.hasJavaEnumFlag) ACC_ENUM else 0, - if (sym.isVarargsMethod) ACC_VARARGS else 0, - if (sym.hasFlag(Flags.SYNCHRONIZED)) ACC_SYNCHRONIZED else 0 - ) - } - - def javaFieldFlags(sym: Symbol) = { - javaFlags(sym) | mkFlags( - if (sym hasAnnotation TransientAttr) asm.Opcodes.ACC_TRANSIENT else 0, - if (sym hasAnnotation VolatileAttr) asm.Opcodes.ACC_VOLATILE else 0, - if (sym.isMutable) 0 else asm.Opcodes.ACC_FINAL - ) - } - - def isTopLevelModule(sym: Symbol): Boolean = - exitingPickler { sym.isModuleClass && !sym.isImplClass && !sym.isNestedClass } - - def isStaticModule(sym: Symbol): Boolean = { - sym.isModuleClass && !sym.isImplClass && !sym.isLifted - } - - // ----------------------------------------------------------------------------------------- - // finding the least upper bound in agreement with the bytecode verifier (given two internal names handed by ASM) - // Background: - // http://gallium.inria.fr/~xleroy/publi/bytecode-verification-JAR.pdf - // http://comments.gmane.org/gmane.comp.java.vm.languages/2293 - // https://issues.scala-lang.org/browse/SI-3872 - // ----------------------------------------------------------------------------------------- - - /** - * Given an internal name (eg "java/lang/Integer") returns the class symbol for it. - * - * Better not to need this method (an example where control flow arrives here is welcome). - * This method is invoked only upon both (1) and (2) below happening: - * (1) providing an asm.ClassWriter with an internal name by other means than javaName() - * (2) forgetting to track the corresponding class-symbol in reverseJavaName. - * - * (The first item is already unlikely because we rely on javaName() - * to do the bookkeeping for entries that should go in innerClassBuffer.) - * - * (We could do completely without this method at the expense of computing stack-map-frames ourselves and - * invoking visitFrame(), but that would require another pass over all instructions.) - * - * Right now I can't think of any invocation of visitSomething() on MethodVisitor - * where we hand an internal name not backed by a reverseJavaName. - * However, I'm leaving this note just in case any such oversight is discovered. - */ - def inameToSymbol(iname: String): Symbol = { - val name = global.newTypeName(iname) - val res0 = - if (nme.isModuleName(name)) rootMirror.getModuleByName(name.dropModule) - else rootMirror.getClassByName(name.replace('/', '.')) // TODO fails for inner classes (but this hasn't been tested). - assert(res0 != NoSymbol) - val res = jsymbol(res0) - res - } - - def jsymbol(sym: Symbol): Symbol = { - if(sym.isJavaDefined && sym.isModuleClass) sym.linkedClassOfClass - else if(sym.isModule) sym.moduleClass - else sym // we track only module-classes and plain-classes - } - - private def superClasses(s: Symbol): List[Symbol] = { - assert(!s.isInterface) - s.superClass match { - case NoSymbol => List(s) - case sc => s :: superClasses(sc) - } - } - - private def firstCommonSuffix(as: List[Symbol], bs: List[Symbol]): Symbol = { - assert(!(as contains NoSymbol)) - assert(!(bs contains NoSymbol)) - var chainA = as - var chainB = bs - var fcs: Symbol = NoSymbol - do { - if (chainB contains chainA.head) fcs = chainA.head - else if (chainA contains chainB.head) fcs = chainB.head - else { - chainA = chainA.tail - chainB = chainB.tail - } - } while(fcs == NoSymbol) - fcs - } - - private def jvmWiseLUB(a: Symbol, b: Symbol): Symbol = { - assert(a.isClass) - assert(b.isClass) - - val res = (a.isInterface, b.isInterface) match { - case (true, true) => - global.lub(List(a.tpe, b.tpe)).typeSymbol // TODO assert == firstCommonSuffix of resp. parents - case (true, false) => - if(b isSubClass a) a else ObjectClass - case (false, true) => - if(a isSubClass b) b else ObjectClass - case _ => - firstCommonSuffix(superClasses(a), superClasses(b)) - } - assert(res != NoSymbol) - res - } - - /* The internal name of the least common ancestor of the types given by inameA and inameB. - It's what ASM needs to know in order to compute stack map frames, http://asm.ow2.org/doc/developer-guide.html#controlflow */ - def getCommonSuperClass(inameA: String, inameB: String): String = { - val a = reverseJavaName.getOrElseUpdate(inameA, inameToSymbol(inameA)) - val b = reverseJavaName.getOrElseUpdate(inameB, inameToSymbol(inameB)) - - // global.lub(List(a.tpe, b.tpe)).typeSymbol.javaBinaryName.toString() - // icodes.lub(icodes.toTypeKind(a.tpe), icodes.toTypeKind(b.tpe)).toType - val lcaSym = jvmWiseLUB(a, b) - val lcaName = lcaSym.javaBinaryName.toString // don't call javaName because that side-effects innerClassBuffer. - val oldsym = reverseJavaName.put(lcaName, lcaSym) - assert(oldsym.isEmpty || (oldsym.get == lcaSym), "somehow we're not managing to compute common-super-class for ASM consumption") - assert(lcaName != "scala/Any") - - lcaName // TODO ASM caches the answer during the lifetime of a ClassWriter. We outlive that. Do some caching. - } - - class CClassWriter(flags: Int) extends asm.ClassWriter(flags) { - override def getCommonSuperClass(iname1: String, iname2: String): String = { - GenASM.this.getCommonSuperClass(iname1, iname2) - } - } - - // ----------------------------------------------------------------------------------------- - // constants - // ----------------------------------------------------------------------------------------- - - private val classfileVersion: Int = settings.target.value match { - case "jvm-1.5" => asm.Opcodes.V1_5 - case "jvm-1.6" => asm.Opcodes.V1_6 - case "jvm-1.7" => asm.Opcodes.V1_7 - case "jvm-1.8" => asm.Opcodes.V1_8 - } - - private val majorVersion: Int = (classfileVersion & 0xFF) - private val emitStackMapFrame = (majorVersion >= 50) - - private val extraProc: Int = mkFlags( - asm.ClassWriter.COMPUTE_MAXS, - if(emitStackMapFrame) asm.ClassWriter.COMPUTE_FRAMES else 0 - ) - - val JAVA_LANG_OBJECT = asm.Type.getObjectType("java/lang/Object") - val JAVA_LANG_STRING = asm.Type.getObjectType("java/lang/String") - - /** - * We call many Java varargs methods from ASM library that expect Arra[asm.Type] as argument so - * we override default (compiler-generated) ClassTag so we can provide specialized newArray implementation. - * - * Examples of methods that should pick our definition are: JBuilder.javaType and JPlainBuilder.genMethod. - */ - private implicit val asmTypeTag: scala.reflect.ClassTag[asm.Type] = new scala.reflect.ClassTag[asm.Type] { - def runtimeClass: java.lang.Class[asm.Type] = classOf[asm.Type] - final override def newArray(len: Int): Array[asm.Type] = new Array[asm.Type](len) - } - - /** basic functionality for class file building */ - abstract class JBuilder(bytecodeWriter: BytecodeWriter, needsOutfile: Boolean) { - - val EMPTY_STRING_ARRAY = Array.empty[String] - - val mdesc_arglessvoid = "()V" - - val CLASS_CONSTRUCTOR_NAME = "<clinit>" - val INSTANCE_CONSTRUCTOR_NAME = "<init>" - - // ----------------------------------------------------------------------------------------- - // factory methods - // ----------------------------------------------------------------------------------------- - - /** - * Returns a new ClassWriter for the class given by arguments. - * - * @param access the class's access flags. This parameter also indicates if the class is deprecated. - * - * @param name the internal name of the class. - * - * @param signature the signature of this class. May be <tt>null</tt> if - * the class is not a generic one, and does not extend or implement - * generic classes or interfaces. - * - * @param superName the internal of name of the super class. For interfaces, - * the super class is [[Object]]. May be <tt>null</tt>, but - * only for the [[Object]] class. - * - * @param interfaces the internal names of the class's interfaces (see - * {@link Type#getInternalName() getInternalName}). May be - * <tt>null</tt>. - */ - def createJClass(access: Int, name: String, signature: String, superName: String, interfaces: Array[String]): asm.ClassWriter = { - val cw = new CClassWriter(extraProc) - cw.visit(classfileVersion, - access, name, signature, - superName, interfaces) - - cw - } - - def createJAttribute(name: String, b: Array[Byte], offset: Int, len: Int): asm.Attribute = { - val dest = new Array[Byte](len) - System.arraycopy(b, offset, dest, 0, len) - new asm.CustomAttr(name, dest) - } - - // ----------------------------------------------------------------------------------------- - // utilities useful when emitting plain, mirror, and beaninfo classes. - // ----------------------------------------------------------------------------------------- - - def writeIfNotTooBig(label: String, jclassName: String, jclass: asm.ClassWriter, sym: Symbol) { - try { - val arr = jclass.toByteArray() - val outF: scala.tools.nsc.io.AbstractFile = { - if(needsOutfile) getFile(sym, jclassName, ".class") else null - } - bytecodeWriter.writeClass(label, jclassName, arr, outF) - } catch { - case e: java.lang.RuntimeException if e.getMessage != null && (e.getMessage contains "too large!") => - reporter.error(sym.pos, - s"Could not write class $jclassName because it exceeds JVM code size limits. ${e.getMessage}") - case e: java.io.IOException if e.getMessage != null && (e.getMessage contains "File name too long") => - reporter.error(sym.pos, e.getMessage + "\n" + - "This can happen on some encrypted or legacy file systems. Please see SI-3623 for more details.") - - } - } - - /** Specialized array conversion to prevent calling - * java.lang.reflect.Array.newInstance via TraversableOnce.toArray - */ - def mkArray(xs: Traversable[String]): Array[String] = { val a = new Array[String](xs.size); xs.copyToArray(a); a } - - // ----------------------------------------------------------------------------------------- - // Getters for (JVMS 4.2) internal and unqualified names (represented as JType instances). - // These getters track behind the scenes the inner classes referred to in the class being emitted, - // so as to build the InnerClasses attribute (JVMS 4.7.6) via `addInnerClasses()` - // (which also adds as member classes those inner classes that have been declared, - // thus also covering the case of inner classes declared but otherwise not referred). - // ----------------------------------------------------------------------------------------- - - val innerClassBuffer = mutable.LinkedHashSet[Symbol]() - - /** For given symbol return a symbol corresponding to a class that should be declared as inner class. - * - * For example: - * class A { - * class B - * object C - * } - * - * then method will return: - * NoSymbol for A, - * the same symbol for A.B (corresponding to A$B class), and - * A$C$ symbol for A.C. - */ - def innerClassSymbolFor(s: Symbol): Symbol = - if (s.isClass) s else if (s.isModule) s.moduleClass else NoSymbol - - /** Return the name of this symbol that can be used on the Java platform. It removes spaces from names. - * - * Special handling: - * scala.Nothing erases to scala.runtime.Nothing$ - * scala.Null erases to scala.runtime.Null$ - * - * This is needed because they are not real classes, and they mean - * 'abrupt termination upon evaluation of that expression' or null respectively. - * This handling is done already in GenICode, but here we need to remove - * references from method signatures to these types, because such classes - * cannot exist in the classpath: the type checker will be very confused. - */ - def javaName(sym: Symbol): String = { - - /* - * Checks if given symbol corresponds to inner class/object and add it to innerClassBuffer - * - * Note: This method is called recursively thus making sure that we add complete chain - * of inner class all until root class. - */ - def collectInnerClass(s: Symbol): Unit = { - // TODO: some enteringFlatten { ... } which accounts for - // being nested in parameterized classes (if we're going to selectively flatten.) - val x = innerClassSymbolFor(s) - if(x ne NoSymbol) { - assert(x.isClass, "not an inner-class symbol") - // impl classes are considered top-level, see comment in BTypes - val isInner = !considerAsTopLevelImplementationArtifact(s) && !x.rawowner.isPackageClass - if (isInner) { - innerClassBuffer += x - collectInnerClass(x.rawowner) - } - } - } - - collectInnerClass(sym) - - val hasInternalName = sym.isClass || sym.isModuleNotMethod - val cachedJN = javaNameCache.getOrElseUpdate(sym, { - if (hasInternalName) { sym.javaBinaryName } - else { sym.javaSimpleName } - }) - - if(emitStackMapFrame && hasInternalName) { - val internalName = cachedJN.toString() - val trackedSym = jsymbol(sym) - reverseJavaName.get(internalName) match { - case None => - reverseJavaName.put(internalName, trackedSym) - case Some(oldsym) => - // TODO: `duplicateOk` seems pretty ad-hoc (a more aggressive version caused SI-9356 because it called oldSym.exists, which failed in the unpickler; see also SI-5031) - def duplicateOk = oldsym == NoSymbol || trackedSym == NoSymbol || (syntheticCoreClasses contains oldsym) || (oldsym.isModuleClass && (oldsym.sourceModule == trackedSym.sourceModule)) - if (oldsym != trackedSym && !duplicateOk) - devWarning(s"""|Different class symbols have the same bytecode-level internal name: - | name: $internalName - | oldsym: ${oldsym.fullNameString} - | tracked: ${trackedSym.fullNameString}""".stripMargin) - } - } - - cachedJN.toString - } - - def descriptor(t: Type): String = { javaType(t).getDescriptor } - def descriptor(k: TypeKind): String = { javaType(k).getDescriptor } - def descriptor(s: Symbol): String = { javaType(s).getDescriptor } - - def javaType(tk: TypeKind): asm.Type = { - if(tk.isValueType) { - if(tk.isIntSizedType) { - (tk: @unchecked) match { - case BOOL => asm.Type.BOOLEAN_TYPE - case BYTE => asm.Type.BYTE_TYPE - case SHORT => asm.Type.SHORT_TYPE - case CHAR => asm.Type.CHAR_TYPE - case INT => asm.Type.INT_TYPE - } - } else { - (tk: @unchecked) match { - case UNIT => asm.Type.VOID_TYPE - case LONG => asm.Type.LONG_TYPE - case FLOAT => asm.Type.FLOAT_TYPE - case DOUBLE => asm.Type.DOUBLE_TYPE - } - } - } else { - assert(!tk.isBoxedType, tk) // documentation (BOXED matches none below anyway) - (tk: @unchecked) match { - case REFERENCE(cls) => asm.Type.getObjectType(javaName(cls)) - case ARRAY(elem) => javaArrayType(javaType(elem)) - } - } - } - - def javaType(t: Type): asm.Type = javaType(toTypeKind(t)) - - def javaType(s: Symbol): asm.Type = { - if (s.isMethod) { - val resT: asm.Type = if (s.isClassConstructor) asm.Type.VOID_TYPE else javaType(s.tpe.resultType) - asm.Type.getMethodType( resT, (s.tpe.paramTypes map javaType): _*) - } else { javaType(s.tpe) } - } - - def javaArrayType(elem: asm.Type): asm.Type = { asm.Type.getObjectType("[" + elem.getDescriptor) } - - def isDeprecated(sym: Symbol): Boolean = { sym.annotations exists (_ matches definitions.DeprecatedAttr) } - - def addInnerClasses(csym: Symbol, jclass: asm.ClassVisitor, isMirror: Boolean = false) { - /* The outer name for this inner class. Note that it returns null - * when the inner class should not get an index in the constant pool. - * That means non-member classes (anonymous). See Section 4.7.5 in the JVMS. - */ - def outerName(innerSym: Symbol): String = { - if (isAnonymousOrLocalClass(innerSym)) - null - else { - val outerName = javaName(innerSym.rawowner) - if (isTopLevelModule(innerSym.rawowner)) "" + TermName(outerName).dropModule - else outerName - } - } - - def innerName(innerSym: Symbol): String = { - // phase travel necessary: after flatten, the name includes the name of outer classes. - // if some outer name contains $anon, a non-anon class is considered anon. - if (exitingPickler(innerSym.isAnonymousClass || innerSym.isAnonymousFunction)) null - else innerSym.rawname + innerSym.moduleSuffix - } - - val linkedClass = exitingPickler(csym.linkedClassOfClass) // linkedCoC does not work properly in late phases - - innerClassBuffer ++= { - val members = exitingPickler(memberClassesForInnerClassTable(csym)) - // lambdalift makes all classes (also local, anonymous) members of their enclosing class - val allNested = exitingPhase(currentRun.lambdaliftPhase)(memberClassesForInnerClassTable(csym)) - val nested = { - // Classes nested in value classes are nested in the companion at this point. For InnerClass / - // EnclosingMethod, we use the value class as the outer class. So we remove nested classes - // from the companion that were originally nested in the value class. - if (exitingPickler(linkedClass.isDerivedValueClass)) allNested.filterNot(classOriginallyNestedInClass(_, linkedClass)) - else allNested - } - - // for the mirror class, we take the members of the companion module class (Java compat, see doc in BTypes.scala). - // for module classes, we filter out those members. - if (isMirror) members - else if (isTopLevelModule(csym)) nested diff members - else nested - } - - if (!considerAsTopLevelImplementationArtifact(csym)) { - // If this is a top-level non-impl class, add members of the companion object. These are the - // classes for which we change the InnerClass entry to allow using them from Java. - // We exclude impl classes: if the classfile for the impl class exists on the classpath, a - // linkedClass symbol is found for which isTopLevelModule is true, so we end up searching - // members of that weird impl-class-module-class-symbol. that search probably cannot return - // any classes, but it's better to exclude it. - if (linkedClass != NoSymbol && isTopLevelModule(linkedClass)) { - // phase travel to exitingPickler: this makes sure that memberClassesForInnerClassTable only - // sees member classes, not local classes that were lifted by lambdalift. - innerClassBuffer ++= exitingPickler(memberClassesForInnerClassTable(linkedClass)) - } - - // Classes nested in value classes are nested in the companion at this point. For InnerClass / - // EnclosingMethod we use the value class as enclosing class. Here we search nested classes - // in the companion that were originally nested in the value class, and we add them as nested - // in the value class. - if (linkedClass != NoSymbol && exitingPickler(csym.isDerivedValueClass)) { - val moduleMemberClasses = exitingPhase(currentRun.lambdaliftPhase)(memberClassesForInnerClassTable(linkedClass)) - innerClassBuffer ++= moduleMemberClasses.filter(classOriginallyNestedInClass(_, csym)) - } - } - - val allInners: List[Symbol] = innerClassBuffer.toList filterNot deadCode.elidedClosures - - if (allInners.nonEmpty) { - debuglog(csym.fullName('.') + " contains " + allInners.size + " inner classes.") - - // entries ready to be serialized into the classfile, used to detect duplicates. - val entries = mutable.Map.empty[String, String] - - // sort them so inner classes succeed their enclosing class to satisfy the Eclipse Java compiler - for (innerSym <- allInners sortBy (_.name.length)) { // TODO why not sortBy (_.name.toString()) ?? - val flagsWithFinal: Int = mkFlags( - // See comment in BTypes, when is a class marked static in the InnerClass table. - if (isOriginallyStaticOwner(innerSym.originalOwner)) asm.Opcodes.ACC_STATIC else 0, - (if (innerSym.isJava) javaClassfileFlags(innerSym) else javaFlags(innerSym)) & ~asm.Opcodes.ACC_STATIC, - if(isDeprecated(innerSym)) asm.Opcodes.ACC_DEPRECATED else 0 // ASM pseudo-access flag - ) & (BCodeAsmCommon.INNER_CLASSES_FLAGS | asm.Opcodes.ACC_DEPRECATED) - val flags = if (innerSym.isModuleClass) flagsWithFinal & ~asm.Opcodes.ACC_FINAL else flagsWithFinal // For SI-5676, object overriding. - val jname = javaName(innerSym) // never null - val oname = outerName(innerSym) // null when method-enclosed - val iname = innerName(innerSym) // null for anonymous inner class - - // Mimicking javap inner class output - debuglog( - if (oname == null || iname == null) "//class " + jname - else "//%s=class %s of class %s".format(iname, jname, oname) - ) - - assert(jname != null, "javaName is broken.") // documentation - val doAdd = entries.get(jname) match { - // TODO is it ok for prevOName to be null? (Someone should really document the invariants of the InnerClasses bytecode attribute) - case Some(prevOName) => - // this occurs e.g. when innerClassBuffer contains both class Thread$State, object Thread$State, - // i.e. for them it must be the case that oname == java/lang/Thread - assert(prevOName == oname, "duplicate") - false - case None => true - } - - if(doAdd) { - entries += (jname -> oname) - jclass.visitInnerClass(jname, oname, iname, flags) - } - - /* - * TODO assert (JVMS 4.7.6 The InnerClasses attribute) - * If a class file has a version number that is greater than or equal to 51.0, and - * has an InnerClasses attribute in its attributes table, then for all entries in the - * classes array of the InnerClasses attribute, the value of the - * outer_class_info_index item must be zero if the value of the - * inner_name_index item is zero. - */ - - } - } - } - - } // end of class JBuilder - - - /** functionality for building plain and mirror classes */ - abstract class JCommonBuilder(bytecodeWriter: BytecodeWriter, needsOutfile: Boolean) extends JBuilder(bytecodeWriter, needsOutfile) { - - def debugLevel = settings.debuginfo.indexOfChoice - - val emitSource = debugLevel >= 1 - val emitLines = debugLevel >= 2 - val emitVars = debugLevel >= 3 - - // ----------------------------------------------------------------------------------------- - // more constants - // ----------------------------------------------------------------------------------------- - - val PublicStatic = asm.Opcodes.ACC_PUBLIC | asm.Opcodes.ACC_STATIC - val PublicStaticFinal = asm.Opcodes.ACC_PUBLIC | asm.Opcodes.ACC_STATIC | asm.Opcodes.ACC_FINAL - - val strMODULE_INSTANCE_FIELD = nme.MODULE_INSTANCE_FIELD.toString - - // ----------------------------------------------------------------------------------------- - // Custom attribute (JVMS 4.7.1) "ScalaSig" used as marker only - // i.e., the pickle is contained in a custom annotation, see: - // (1) `addAnnotations()`, - // (2) SID # 10 (draft) - Storage of pickled Scala signatures in class files, http://www.scala-lang.org/sid/10 - // (3) SID # 5 - Internals of Scala Annotations, http://www.scala-lang.org/sid/5 - // That annotation in turn is not related to the "java-generic-signature" (JVMS 4.7.9) - // other than both ending up encoded as attributes (JVMS 4.7) - // (with the caveat that the "ScalaSig" attribute is associated to some classes, - // while the "Signature" attribute can be associated to classes, methods, and fields.) - // ----------------------------------------------------------------------------------------- - - val versionPickle = { - val vp = new PickleBuffer(new Array[Byte](16), -1, 0) - assert(vp.writeIndex == 0, vp) - vp writeNat PickleFormat.MajorVersion - vp writeNat PickleFormat.MinorVersion - vp writeNat 0 - vp - } - - def pickleMarkerLocal = { - createJAttribute(tpnme.ScalaSignatureATTR.toString, versionPickle.bytes, 0, versionPickle.writeIndex) - } - - def pickleMarkerForeign = { - createJAttribute(tpnme.ScalaATTR.toString, new Array[Byte](0), 0, 0) - } - - /** Returns a ScalaSignature annotation if it must be added to this class, none otherwise. - * This annotation must be added to the class' annotations list when generating them. - * - * Depending on whether the returned option is defined, it adds to `jclass` one of: - * (a) the ScalaSig marker attribute - * (indicating that a scala-signature-annotation aka pickle is present in this class); or - * (b) the Scala marker attribute - * (indicating that a scala-signature-annotation aka pickle is to be found in another file). - * - * - * @param jclassName The class file that is being readied. - * @param sym The symbol for which the signature has been entered in the symData map. - * This is different than the symbol - * that is being generated in the case of a mirror class. - * @return An option that is: - * - defined and contains an AnnotationInfo of the ScalaSignature type, - * instantiated with the pickle signature for sym. - * - empty if the jclass/sym pair must not contain a pickle. - * - */ - def getAnnotPickle(jclassName: String, sym: Symbol): Option[AnnotationInfo] = { - currentRun.symData get sym match { - case Some(pickle) if !nme.isModuleName(newTermName(jclassName)) => - val scalaAnnot = { - val sigBytes = ScalaSigBytes(pickle.bytes.take(pickle.writeIndex)) - AnnotationInfo(sigBytes.sigAnnot, Nil, List((nme.bytes, sigBytes))) - } - pickledBytes += pickle.writeIndex - currentRun.symData -= sym - currentRun.symData -= sym.companionSymbol - Some(scalaAnnot) - case _ => - None - } - } - - /** - * Quoting from JVMS 4.7.5 The Exceptions Attribute - * "The Exceptions attribute indicates which checked exceptions a method may throw. - * There may be at most one Exceptions attribute in each method_info structure." - * - * The contents of that attribute are determined by the `String[] exceptions` argument to ASM's ClassVisitor.visitMethod() - * This method returns such list of internal names. - */ - def getExceptions(excs: List[AnnotationInfo]): List[String] = - for (ThrownException(exc) <- excs.distinct) - yield javaName(exc) - - def getCurrentCUnit(): CompilationUnit - - def getGenericSignature(sym: Symbol, owner: Symbol) = self.getGenericSignature(sym, owner, getCurrentCUnit()) - - def emitArgument(av: asm.AnnotationVisitor, - name: String, - arg: ClassfileAnnotArg) { - (arg: @unchecked) match { - - case LiteralAnnotArg(const) => - if(const.isNonUnitAnyVal) { av.visit(name, const.value) } - else { - const.tag match { - case StringTag => - assert(const.value != null, const) // TODO this invariant isn't documented in `case class Constant` - av.visit(name, const.stringValue) // `stringValue` special-cases null, but that execution path isn't exercised for a const with StringTag - case ClazzTag => av.visit(name, javaType(const.typeValue)) - case EnumTag => - val edesc = descriptor(const.tpe) // the class descriptor of the enumeration class. - val evalue = const.symbolValue.name.toString // value the actual enumeration value. - av.visitEnum(name, edesc, evalue) - } - } - - case sb@ScalaSigBytes(bytes) => - // see http://www.scala-lang.org/sid/10 (Storage of pickled Scala signatures in class files) - // also JVMS Sec. 4.7.16.1 The element_value structure and JVMS Sec. 4.4.7 The CONSTANT_Utf8_info Structure. - if (sb.fitsInOneString) - av.visit(name, strEncode(sb)) - else { - val arrAnnotV: asm.AnnotationVisitor = av.visitArray(name) - for(arg <- arrEncode(sb)) { arrAnnotV.visit(name, arg) } - arrAnnotV.visitEnd() - } - // for the lazy val in ScalaSigBytes to be GC'ed, the invoker of emitAnnotations() should hold the ScalaSigBytes in a method-local var that doesn't escape. - - case ArrayAnnotArg(args) => - val arrAnnotV: asm.AnnotationVisitor = av.visitArray(name) - for(arg <- args) { emitArgument(arrAnnotV, null, arg) } - arrAnnotV.visitEnd() - - case NestedAnnotArg(annInfo) => - val AnnotationInfo(typ, args, assocs) = annInfo - assert(args.isEmpty, args) - val desc = descriptor(typ) // the class descriptor of the nested annotation class - val nestedVisitor = av.visitAnnotation(name, desc) - emitAssocs(nestedVisitor, assocs) - } - } - - def emitAssocs(av: asm.AnnotationVisitor, assocs: List[(Name, ClassfileAnnotArg)]) { - for ((name, value) <- assocs) { - emitArgument(av, name.toString(), value) - } - av.visitEnd() - } - - def emitAnnotations(cw: asm.ClassVisitor, annotations: List[AnnotationInfo]) { - for(annot <- annotations; if shouldEmitAnnotation(annot)) { - val AnnotationInfo(typ, args, assocs) = annot - assert(args.isEmpty, args) - val av = cw.visitAnnotation(descriptor(typ), isRuntimeVisible(annot)) - emitAssocs(av, assocs) - } - } - - def emitAnnotations(mw: asm.MethodVisitor, annotations: List[AnnotationInfo]) { - for(annot <- annotations; if shouldEmitAnnotation(annot)) { - val AnnotationInfo(typ, args, assocs) = annot - assert(args.isEmpty, args) - val av = mw.visitAnnotation(descriptor(typ), isRuntimeVisible(annot)) - emitAssocs(av, assocs) - } - } - - def emitAnnotations(fw: asm.FieldVisitor, annotations: List[AnnotationInfo]) { - for(annot <- annotations; if shouldEmitAnnotation(annot)) { - val AnnotationInfo(typ, args, assocs) = annot - assert(args.isEmpty, args) - val av = fw.visitAnnotation(descriptor(typ), isRuntimeVisible(annot)) - emitAssocs(av, assocs) - } - } - - def emitParamAnnotations(jmethod: asm.MethodVisitor, pannotss: List[List[AnnotationInfo]]) { - val annotationss = pannotss map (_ filter shouldEmitAnnotation) - if (annotationss forall (_.isEmpty)) return - for ((annots, idx) <- annotationss.zipWithIndex; - annot <- annots) { - val AnnotationInfo(typ, args, assocs) = annot - assert(args.isEmpty, args) - val pannVisitor: asm.AnnotationVisitor = jmethod.visitParameterAnnotation(idx, descriptor(typ), isRuntimeVisible(annot)) - emitAssocs(pannVisitor, assocs) - } - } - - /** Adds a @remote annotation, actual use unknown. - * - * Invoked from genMethod() and addForwarder(). - */ - def addRemoteExceptionAnnot(isRemoteClass: Boolean, isJMethodPublic: Boolean, meth: Symbol) { - val needsAnnotation = ( - ( isRemoteClass || - isRemote(meth) && isJMethodPublic - ) && !(meth.throwsAnnotations contains RemoteExceptionClass) - ) - if (needsAnnotation) { - val c = Constant(RemoteExceptionClass.tpe) - val arg = Literal(c) setType c.tpe - meth.addAnnotation(appliedType(ThrowsClass, c.tpe), arg) - } - } - - // ----------------------------------------------------------------------------------------- - // Static forwarders (related to mirror classes but also present in - // a plain class lacking companion module, for details see `isCandidateForForwarders`). - // ----------------------------------------------------------------------------------------- - - /** Add a forwarder for method m. Used only from addForwarders(). */ - private def addForwarder(isRemoteClass: Boolean, jclass: asm.ClassVisitor, module: Symbol, m: Symbol) { - val moduleName = javaName(module) - val methodInfo = module.thisType.memberInfo(m) - val paramJavaTypes: List[asm.Type] = methodInfo.paramTypes map javaType - // val paramNames = 0 until paramJavaTypes.length map ("x_" + _) - - /* Forwarders must not be marked final, - * as the JVM will not allow redefinition of a final static method, - * and we don't know what classes might be subclassing the companion class. See SI-4827. - */ - // TODO: evaluate the other flags we might be dropping on the floor here. - // TODO: ACC_SYNTHETIC ? - val flags = PublicStatic | ( - if (m.isVarargsMethod) asm.Opcodes.ACC_VARARGS else 0 - ) - - // TODO needed? for(ann <- m.annotations) { ann.symbol.initialize } - val jgensig = staticForwarderGenericSignature(m, module, getCurrentCUnit()) - addRemoteExceptionAnnot(isRemoteClass, hasPublicBitSet(flags), m) - val (throws, others) = m.annotations partition (_.symbol == ThrowsClass) - val thrownExceptions: List[String] = getExceptions(throws) - - val jReturnType = javaType(methodInfo.resultType) - val mdesc = asm.Type.getMethodDescriptor(jReturnType, paramJavaTypes: _*) - val mirrorMethodName = javaName(m) - val mirrorMethod: asm.MethodVisitor = jclass.visitMethod( - flags, - mirrorMethodName, - mdesc, - jgensig, - mkArray(thrownExceptions) - ) - - // typestate: entering mode with valid call sequences: - // [ visitAnnotationDefault ] ( visitAnnotation | visitParameterAnnotation | visitAttribute )* - - emitAnnotations(mirrorMethod, others) - emitParamAnnotations(mirrorMethod, m.info.params.map(_.annotations)) - - // typestate: entering mode with valid call sequences: - // visitCode ( visitFrame | visitXInsn | visitLabel | visitTryCatchBlock | visitLocalVariable | visitLineNumber )* visitMaxs ] visitEnd - - mirrorMethod.visitCode() - - mirrorMethod.visitFieldInsn(asm.Opcodes.GETSTATIC, moduleName, strMODULE_INSTANCE_FIELD, descriptor(module)) - - var index = 0 - for(jparamType <- paramJavaTypes) { - mirrorMethod.visitVarInsn(jparamType.getOpcode(asm.Opcodes.ILOAD), index) - assert(jparamType.getSort() != asm.Type.METHOD, jparamType) - index += jparamType.getSize() - } - - mirrorMethod.visitMethodInsn(asm.Opcodes.INVOKEVIRTUAL, moduleName, mirrorMethodName, javaType(m).getDescriptor, false) - mirrorMethod.visitInsn(jReturnType.getOpcode(asm.Opcodes.IRETURN)) - - mirrorMethod.visitMaxs(0, 0) // just to follow protocol, dummy arguments - mirrorMethod.visitEnd() - - } - - /** Add forwarders for all methods defined in `module` that don't conflict - * with methods in the companion class of `module`. A conflict arises when - * a method with the same name is defined both in a class and its companion object: - * method signature is not taken into account. - */ - def addForwarders(isRemoteClass: Boolean, jclass: asm.ClassVisitor, jclassName: String, moduleClass: Symbol) { - assert(moduleClass.isModuleClass, moduleClass) - debuglog("Dumping mirror class for object: " + moduleClass) - - val linkedClass = moduleClass.companionClass - lazy val conflictingNames: Set[Name] = { - (linkedClass.info.members collect { case sym if sym.name.isTermName => sym.name }).toSet - } - debuglog("Potentially conflicting names for forwarders: " + conflictingNames) - - for (m <- moduleClass.info.membersBasedOnFlags(ExcludedForwarderFlags, Flags.METHOD)) { - if (m.isType || m.isDeferred || (m.owner eq ObjectClass) || m.isConstructor) - debuglog(s"No forwarder for '$m' from $jclassName to '$moduleClass'") - else if (conflictingNames(m.name)) - log(s"No forwarder for $m due to conflict with " + linkedClass.info.member(m.name)) - else if (m.hasAccessBoundary) - log(s"No forwarder for non-public member $m") - else { - debuglog(s"Adding static forwarder for '$m' from $jclassName to '$moduleClass'") - addForwarder(isRemoteClass, jclass, moduleClass, m) - } - } - } - - } // end of class JCommonBuilder - - - trait JAndroidBuilder { - self: JPlainBuilder => - - def isAndroidParcelableClass(sym: Symbol) = - (AndroidParcelableInterface != NoSymbol) && - (sym.parentSymbols contains AndroidParcelableInterface) - - /* Typestate: should be called before emitting fields (because it adds an IField to the current IClass). */ - def addCreatorCode(block: BasicBlock) { - val fieldSymbol = ( - clasz.symbol.newValue(androidFieldName, NoPosition, Flags.STATIC | Flags.FINAL) - setInfo AndroidCreatorClass.tpe - ) - val methodSymbol = definitions.getMember(clasz.symbol.companionModule, androidFieldName) - clasz addField new IField(fieldSymbol) - block emit CALL_METHOD(methodSymbol, Static(onInstance = false)) - block emit STORE_FIELD(fieldSymbol, isStatic = true) - } - - def legacyAddCreatorCode(clinit: asm.MethodVisitor) { - val creatorType: asm.Type = javaType(AndroidCreatorClass) - val tdesc_creator = creatorType.getDescriptor - - jclass.visitField( - PublicStaticFinal, - androidFieldName.toString, - tdesc_creator, - null, // no java-generic-signature - null // no initial value - ).visitEnd() - - val moduleName = javaName(clasz.symbol)+"$" - - // GETSTATIC `moduleName`.MODULE$ : `moduleName`; - clinit.visitFieldInsn( - asm.Opcodes.GETSTATIC, - moduleName, - strMODULE_INSTANCE_FIELD, - asm.Type.getObjectType(moduleName).getDescriptor - ) - - // INVOKEVIRTUAL `moduleName`.CREATOR() : android.os.Parcelable$Creator; - clinit.visitMethodInsn( - asm.Opcodes.INVOKEVIRTUAL, - moduleName, - androidFieldName.toString, - asm.Type.getMethodDescriptor(creatorType, Array.empty[asm.Type]: _*), - false - ) - - // PUTSTATIC `thisName`.CREATOR; - clinit.visitFieldInsn( - asm.Opcodes.PUTSTATIC, - thisName, - androidFieldName.toString, - tdesc_creator - ) - } - - } // end of trait JAndroidBuilder - - /** Map from type kinds to the Java reference types. - * It is used to push class literals onto the operand stack. - * @see Predef.classOf - * @see genConstant() - */ - private val classLiteral = immutable.Map[TypeKind, asm.Type]( - UNIT -> asm.Type.getObjectType("java/lang/Void"), - BOOL -> asm.Type.getObjectType("java/lang/Boolean"), - BYTE -> asm.Type.getObjectType("java/lang/Byte"), - SHORT -> asm.Type.getObjectType("java/lang/Short"), - CHAR -> asm.Type.getObjectType("java/lang/Character"), - INT -> asm.Type.getObjectType("java/lang/Integer"), - LONG -> asm.Type.getObjectType("java/lang/Long"), - FLOAT -> asm.Type.getObjectType("java/lang/Float"), - DOUBLE -> asm.Type.getObjectType("java/lang/Double") - ) - - def isNonUnitValueTK(tk: TypeKind): Boolean = { tk.isValueType && tk != UNIT } - - case class MethodNameAndType(mname: String, mdesc: String) - - private val jBoxTo: Map[TypeKind, MethodNameAndType] = { - Map( - BOOL -> MethodNameAndType("boxToBoolean", "(Z)Ljava/lang/Boolean;" ) , - BYTE -> MethodNameAndType("boxToByte", "(B)Ljava/lang/Byte;" ) , - CHAR -> MethodNameAndType("boxToCharacter", "(C)Ljava/lang/Character;") , - SHORT -> MethodNameAndType("boxToShort", "(S)Ljava/lang/Short;" ) , - INT -> MethodNameAndType("boxToInteger", "(I)Ljava/lang/Integer;" ) , - LONG -> MethodNameAndType("boxToLong", "(J)Ljava/lang/Long;" ) , - FLOAT -> MethodNameAndType("boxToFloat", "(F)Ljava/lang/Float;" ) , - DOUBLE -> MethodNameAndType("boxToDouble", "(D)Ljava/lang/Double;" ) - ) - } - - private val jUnboxTo: Map[TypeKind, MethodNameAndType] = { - Map( - BOOL -> MethodNameAndType("unboxToBoolean", "(Ljava/lang/Object;)Z") , - BYTE -> MethodNameAndType("unboxToByte", "(Ljava/lang/Object;)B") , - CHAR -> MethodNameAndType("unboxToChar", "(Ljava/lang/Object;)C") , - SHORT -> MethodNameAndType("unboxToShort", "(Ljava/lang/Object;)S") , - INT -> MethodNameAndType("unboxToInt", "(Ljava/lang/Object;)I") , - LONG -> MethodNameAndType("unboxToLong", "(Ljava/lang/Object;)J") , - FLOAT -> MethodNameAndType("unboxToFloat", "(Ljava/lang/Object;)F") , - DOUBLE -> MethodNameAndType("unboxToDouble", "(Ljava/lang/Object;)D") - ) - } - - case class BlockInteval(start: BasicBlock, end: BasicBlock) - - /** builder of plain classes */ - class JPlainBuilder(bytecodeWriter: BytecodeWriter, needsOutfile: Boolean) - extends JCommonBuilder(bytecodeWriter, needsOutfile) - with JAndroidBuilder { - - val MIN_SWITCH_DENSITY = 0.7 - - val StringBuilderClassName = javaName(definitions.StringBuilderClass) - val BoxesRunTime = "scala/runtime/BoxesRunTime" - - val StringBuilderType = asm.Type.getObjectType(StringBuilderClassName) - val mdesc_toString = "()Ljava/lang/String;" - val mdesc_arrayClone = "()Ljava/lang/Object;" - - val tdesc_long = asm.Type.LONG_TYPE.getDescriptor // ie. "J" - - def isParcelableClass = isAndroidParcelableClass(clasz.symbol) - - def serialVUID: Option[Long] = genBCode.serialVUID(clasz.symbol) - - var clasz: IClass = _ // this var must be assigned only by genClass() - var jclass: asm.ClassWriter = _ // the classfile being emitted - var thisName: String = _ // the internal name of jclass - - def thisDescr: String = { - assert(thisName != null, "thisDescr invoked too soon.") - asm.Type.getObjectType(thisName).getDescriptor - } - - def getCurrentCUnit(): CompilationUnit = { clasz.cunit } - - def genClass(c: IClass) { - clasz = c - innerClassBuffer.clear() - - thisName = javaName(c.symbol) // the internal name of the class being emitted - - val ps = c.symbol.info.parents - val superClass: String = if(ps.isEmpty) JAVA_LANG_OBJECT.getInternalName else javaName(ps.head.typeSymbol) - - val ifaces: Array[String] = implementedInterfaces(c.symbol).map(javaName)(collection.breakOut) - - val thisSignature = getGenericSignature(c.symbol, c.symbol.owner) - val flags = mkFlags( - javaFlags(c.symbol), - if(isDeprecated(c.symbol)) asm.Opcodes.ACC_DEPRECATED else 0 // ASM pseudo access flag - ) - jclass = createJClass(flags, - thisName, thisSignature, - superClass, ifaces) - - // typestate: entering mode with valid call sequences: - // [ visitSource ] [ visitOuterClass ] ( visitAnnotation | visitAttribute )* - - if(emitSource) { - jclass.visitSource(c.cunit.source.toString, - null /* SourceDebugExtension */) - } - - enclosingMethodAttribute(clasz.symbol, javaName, javaType(_).getDescriptor) match { - case Some(EnclosingMethodEntry(className, methodName, methodDescriptor)) => - jclass.visitOuterClass(className, methodName, methodDescriptor) - case _ => () - } - - // typestate: entering mode with valid call sequences: - // ( visitAnnotation | visitAttribute )* - - val ssa = getAnnotPickle(thisName, c.symbol) - jclass.visitAttribute(if(ssa.isDefined) pickleMarkerLocal else pickleMarkerForeign) - emitAnnotations(jclass, c.symbol.annotations ++ ssa) - - if (!settings.YskipInlineInfoAttribute.value) - jclass.visitAttribute(InlineInfoAttribute(buildInlineInfoFromClassSymbol(c.symbol, javaName, javaType(_).getDescriptor))) - - // typestate: entering mode with valid call sequences: - // ( visitInnerClass | visitField | visitMethod )* visitEnd - - if (isStaticModule(c.symbol) || isParcelableClass) { - - if (isStaticModule(c.symbol)) { addModuleInstanceField() } - addStaticInit(c.lookupStaticCtor) - - } else { - - for (constructor <- c.lookupStaticCtor) { - addStaticInit(Some(constructor)) - } - val skipStaticForwarders = (c.symbol.isInterface || settings.noForwarders) - if (!skipStaticForwarders) { - val lmoc = c.symbol.companionModule - // add static forwarders if there are no name conflicts; see bugs #363 and #1735 - if (lmoc != NoSymbol) { - // it must be a top level class (name contains no $s) - val isCandidateForForwarders = { - exitingPickler { !(lmoc.name.toString contains '$') && lmoc.hasModuleFlag && !lmoc.isImplClass && !lmoc.isNestedClass } - } - if (isCandidateForForwarders) { - log("Adding static forwarders from '%s' to implementations in '%s'".format(c.symbol, lmoc)) - addForwarders(isRemote(clasz.symbol), jclass, thisName, lmoc.moduleClass) - } - } - } - - } - - // add static serialVersionUID field if `clasz` annotated with `@SerialVersionUID(uid: Long)` - serialVUID foreach { value => - val fieldName = "serialVersionUID" - jclass.visitField( - PublicStaticFinal, - fieldName, - tdesc_long, - null, // no java-generic-signature - value - ).visitEnd() - } - - clasz.fields foreach genField - clasz.methods foreach { im => genMethod(im, c.symbol.isInterface) } - - addInnerClasses(clasz.symbol, jclass) - jclass.visitEnd() - writeIfNotTooBig("" + c.symbol.name, thisName, jclass, c.symbol) - } - - def genField(f: IField) { - debuglog("Adding field: " + f.symbol.fullName) - - val javagensig = getGenericSignature(f.symbol, clasz.symbol) - - val flags = mkFlags( - javaFieldFlags(f.symbol), - if(isDeprecated(f.symbol)) asm.Opcodes.ACC_DEPRECATED else 0 // ASM pseudo access flag - ) - - val jfield: asm.FieldVisitor = jclass.visitField( - flags, - javaName(f.symbol), - javaType(f.symbol.tpe).getDescriptor(), - javagensig, - null // no initial value - ) - - emitAnnotations(jfield, f.symbol.annotations) - jfield.visitEnd() - } - - var method: IMethod = _ - var jmethod: asm.MethodVisitor = _ - var jMethodName: String = _ - - final def emit(opc: Int) { jmethod.visitInsn(opc) } - - def genMethod(m: IMethod, isJInterface: Boolean) { - - def isClosureApply(sym: Symbol): Boolean = { - (sym.name == nme.apply) && - sym.owner.isSynthetic && - sym.owner.tpe.parents.exists { t => - val TypeRef(_, sym, _) = t - FunctionClass.seq contains sym - } - } - - if (m.symbol.isStaticConstructor || definitions.isGetClass(m.symbol)) return - - if (m.params.size > MaximumJvmParameters) { - reporter.error(m.symbol.pos, s"Platform restriction: a parameter list's length cannot exceed $MaximumJvmParameters.") - return - } - - debuglog("Generating method " + m.symbol.fullName) - method = m - computeLocalVarsIndex(m) - - var resTpe: asm.Type = javaType(m.symbol.tpe.resultType) - if (m.symbol.isClassConstructor) - resTpe = asm.Type.VOID_TYPE - - val flags = mkFlags( - javaFlags(m.symbol), - if (isJInterface) asm.Opcodes.ACC_ABSTRACT else 0, - if (m.symbol.isStrictFP) asm.Opcodes.ACC_STRICT else 0, - if (method.native) asm.Opcodes.ACC_NATIVE else 0, // native methods of objects are generated in mirror classes - if(isDeprecated(m.symbol)) asm.Opcodes.ACC_DEPRECATED else 0 // ASM pseudo access flag - ) - - // TODO needed? for(ann <- m.symbol.annotations) { ann.symbol.initialize } - val jgensig = getGenericSignature(m.symbol, clasz.symbol) - addRemoteExceptionAnnot(isRemote(clasz.symbol), hasPublicBitSet(flags), m.symbol) - val (excs, others) = m.symbol.annotations partition (_.symbol == ThrowsClass) - val thrownExceptions: List[String] = getExceptions(excs) - - jMethodName = javaName(m.symbol) - val mdesc = asm.Type.getMethodDescriptor(resTpe, (m.params map (p => javaType(p.kind))): _*) - jmethod = jclass.visitMethod( - flags, - jMethodName, - mdesc, - jgensig, - mkArray(thrownExceptions) - ) - - // TODO param names: (m.params map (p => javaName(p.sym))) - - // typestate: entering mode with valid call sequences: (see ASM Guide, 3.2.1) - // [ visitAnnotationDefault ] ( visitAnnotation | visitParameterAnnotation | visitAttribute )* - - emitAnnotations(jmethod, others) - emitParamAnnotations(jmethod, m.params.map(_.sym.annotations)) - - // typestate: entering mode with valid call sequences: - // [ visitCode ( visitFrame | visitXInsn | visitLabel | visitTryCatchBlock | visitLocalVariable | visitLineNumber )* visitMaxs ] visitEnd - // In addition, the visitXInsn and visitLabel methods must be called in the sequential order of the bytecode instructions of the visited code, - // visitTryCatchBlock must be called before the labels passed as arguments have been visited, and - // the visitLocalVariable and visitLineNumber methods must be called after the labels passed as arguments have been visited. - - val hasAbstractBitSet = ((flags & asm.Opcodes.ACC_ABSTRACT) != 0) - val hasCodeAttribute = (!hasAbstractBitSet && !method.native) - if (hasCodeAttribute) { - - jmethod.visitCode() - - if (emitVars && isClosureApply(method.symbol)) { - // add a fake local for debugging purposes - val outerField = clasz.symbol.info.decl(nme.OUTER_LOCAL) - if (outerField != NoSymbol) { - log("Adding fake local to represent outer 'this' for closure " + clasz) - val _this = - new Local(method.symbol.newVariable(nme.FAKE_LOCAL_THIS), - toTypeKind(outerField.tpe), - false) - m.locals = m.locals ::: List(_this) - computeLocalVarsIndex(m) // since we added a new local, we need to recompute indexes - jmethod.visitVarInsn(asm.Opcodes.ALOAD, 0) - jmethod.visitFieldInsn(asm.Opcodes.GETFIELD, - javaName(clasz.symbol), // field owner - javaName(outerField), // field name - descriptor(outerField) // field descriptor - ) - assert(_this.kind.isReferenceType, _this.kind) - jmethod.visitVarInsn(asm.Opcodes.ASTORE, indexOf(_this)) - } - } - - assert( m.locals forall { local => (m.params contains local) == local.arg }, m.locals ) - - val hasStaticBitSet = ((flags & asm.Opcodes.ACC_STATIC) != 0) - genCode(m, emitVars, hasStaticBitSet) - - // visitMaxs needs to be called according to the protocol. The arguments will be ignored - // since maximums (and stack map frames) are computed. See ASM Guide, Section 3.2.1, - // section "ClassWriter options" - jmethod.visitMaxs(0, 0) - } - - jmethod.visitEnd() - - } - - def addModuleInstanceField() { - val fv = - jclass.visitField(PublicStaticFinal, // TODO confirm whether we really don't want ACC_SYNTHETIC nor ACC_DEPRECATED - strMODULE_INSTANCE_FIELD, - thisDescr, - null, // no java-generic-signature - null // no initial value - ) - - // typestate: entering mode with valid call sequences: - // ( visitAnnotation | visitAttribute )* visitEnd. - - fv.visitEnd() - } - - - /* Typestate: should be called before being done with emitting fields (because it invokes addCreatorCode() which adds an IField to the current IClass). */ - def addStaticInit(mopt: Option[IMethod]) { - - val clinitMethod: asm.MethodVisitor = jclass.visitMethod( - PublicStatic, // TODO confirm whether we really don't want ACC_SYNTHETIC nor ACC_DEPRECATED - CLASS_CONSTRUCTOR_NAME, - mdesc_arglessvoid, - null, // no java-generic-signature - null // no throwable exceptions - ) - - mopt match { - - case Some(m) => - - val oldLastBlock = m.lastBlock - val lastBlock = m.newBlock() - oldLastBlock.replaceInstruction(oldLastBlock.length - 1, JUMP(lastBlock)) - - if (isStaticModule(clasz.symbol)) { - // call object's private ctor from static ctor - lastBlock emit NEW(REFERENCE(m.symbol.enclClass)) - lastBlock emit CALL_METHOD(m.symbol.enclClass.primaryConstructor, Static(onInstance = true)) - } - - if (isParcelableClass) { addCreatorCode(lastBlock) } - - lastBlock emit RETURN(UNIT) - lastBlock.close() - - method = m - jmethod = clinitMethod - jMethodName = CLASS_CONSTRUCTOR_NAME - jmethod.visitCode() - computeLocalVarsIndex(m) - genCode(m, emitVars = false, isStatic = true) - jmethod.visitMaxs(0, 0) // just to follow protocol, dummy arguments - jmethod.visitEnd() - - case None => - clinitMethod.visitCode() - legacyStaticInitializer(clinitMethod) - clinitMethod.visitMaxs(0, 0) // just to follow protocol, dummy arguments - clinitMethod.visitEnd() - - } - } - - /* used only from addStaticInit() */ - private def legacyStaticInitializer(clinit: asm.MethodVisitor) { - if (isStaticModule(clasz.symbol)) { - clinit.visitTypeInsn(asm.Opcodes.NEW, thisName) - clinit.visitMethodInsn(asm.Opcodes.INVOKESPECIAL, - thisName, INSTANCE_CONSTRUCTOR_NAME, mdesc_arglessvoid, false) - } - - if (isParcelableClass) { legacyAddCreatorCode(clinit) } - - clinit.visitInsn(asm.Opcodes.RETURN) - } - - // ----------------------------------------------------------------------------------------- - // Emitting bytecode instructions. - // ----------------------------------------------------------------------------------------- - - private def genConstant(mv: asm.MethodVisitor, const: Constant) { - const.tag match { - - case BooleanTag => jcode.boolconst(const.booleanValue) - - case ByteTag => jcode.iconst(const.byteValue.toInt) - case ShortTag => jcode.iconst(const.shortValue.toInt) - case CharTag => jcode.iconst(const.charValue) - case IntTag => jcode.iconst(const.intValue) - - case LongTag => jcode.lconst(const.longValue) - case FloatTag => jcode.fconst(const.floatValue) - case DoubleTag => jcode.dconst(const.doubleValue) - - case UnitTag => () - - case StringTag => - assert(const.value != null, const) // TODO this invariant isn't documented in `case class Constant` - mv.visitLdcInsn(const.stringValue) // `stringValue` special-cases null, but not for a const with StringTag - - case NullTag => mv.visitInsn(asm.Opcodes.ACONST_NULL) - - case ClazzTag => - val kind = toTypeKind(const.typeValue) - val toPush: asm.Type = - if (kind.isValueType) classLiteral(kind) - else javaType(kind) - mv.visitLdcInsn(toPush) - - case EnumTag => - val sym = const.symbolValue - mv.visitFieldInsn( - asm.Opcodes.GETSTATIC, - javaName(sym.owner), - javaName(sym), - javaType(sym.tpe.underlying).getDescriptor() - ) - - case _ => abort("Unknown constant value: " + const) - } - } - - /** Just a namespace for utilities that encapsulate MethodVisitor idioms. - * In the ASM world, org.objectweb.asm.commons.InstructionAdapter plays a similar role, - * but the methods here allow choosing when to transition from ICode to ASM types - * (including not at all, e.g. for performance). - */ - object jcode { - - import asm.Opcodes - - final def boolconst(b: Boolean) { iconst(if(b) 1 else 0) } - - def iconst(cst: Char) { iconst(cst.toInt) } - def iconst(cst: Int) { - if (cst >= -1 && cst <= 5) { - jmethod.visitInsn(Opcodes.ICONST_0 + cst) - } else if (cst >= java.lang.Byte.MIN_VALUE && cst <= java.lang.Byte.MAX_VALUE) { - jmethod.visitIntInsn(Opcodes.BIPUSH, cst) - } else if (cst >= java.lang.Short.MIN_VALUE && cst <= java.lang.Short.MAX_VALUE) { - jmethod.visitIntInsn(Opcodes.SIPUSH, cst) - } else { - jmethod.visitLdcInsn(new Integer(cst)) - } - } - - def lconst(cst: Long) { - if (cst == 0L || cst == 1L) { - jmethod.visitInsn(Opcodes.LCONST_0 + cst.asInstanceOf[Int]) - } else { - jmethod.visitLdcInsn(new java.lang.Long(cst)) - } - } - - def fconst(cst: Float) { - val bits: Int = java.lang.Float.floatToIntBits(cst) - if (bits == 0L || bits == 0x3f800000 || bits == 0x40000000) { // 0..2 - jmethod.visitInsn(Opcodes.FCONST_0 + cst.asInstanceOf[Int]) - } else { - jmethod.visitLdcInsn(new java.lang.Float(cst)) - } - } - - def dconst(cst: Double) { - val bits: Long = java.lang.Double.doubleToLongBits(cst) - if (bits == 0L || bits == 0x3ff0000000000000L) { // +0.0d and 1.0d - jmethod.visitInsn(Opcodes.DCONST_0 + cst.asInstanceOf[Int]) - } else { - jmethod.visitLdcInsn(new java.lang.Double(cst)) - } - } - - def newarray(elem: TypeKind) { - if(elem.isRefOrArrayType) { - jmethod.visitTypeInsn(Opcodes.ANEWARRAY, javaType(elem).getInternalName) - } else { - val rand = { - if(elem.isIntSizedType) { - (elem: @unchecked) match { - case BOOL => Opcodes.T_BOOLEAN - case BYTE => Opcodes.T_BYTE - case SHORT => Opcodes.T_SHORT - case CHAR => Opcodes.T_CHAR - case INT => Opcodes.T_INT - } - } else { - (elem: @unchecked) match { - case LONG => Opcodes.T_LONG - case FLOAT => Opcodes.T_FLOAT - case DOUBLE => Opcodes.T_DOUBLE - } - } - } - jmethod.visitIntInsn(Opcodes.NEWARRAY, rand) - } - } - - - def load( idx: Int, tk: TypeKind) { emitVarInsn(Opcodes.ILOAD, idx, tk) } - def store(idx: Int, tk: TypeKind) { emitVarInsn(Opcodes.ISTORE, idx, tk) } - - def aload( tk: TypeKind) { emitTypeBased(aloadOpcodes, tk) } - def astore(tk: TypeKind) { emitTypeBased(astoreOpcodes, tk) } - - def neg(tk: TypeKind) { emitPrimitive(negOpcodes, tk) } - def add(tk: TypeKind) { emitPrimitive(addOpcodes, tk) } - def sub(tk: TypeKind) { emitPrimitive(subOpcodes, tk) } - def mul(tk: TypeKind) { emitPrimitive(mulOpcodes, tk) } - def div(tk: TypeKind) { emitPrimitive(divOpcodes, tk) } - def rem(tk: TypeKind) { emitPrimitive(remOpcodes, tk) } - - def invokespecial(owner: String, name: String, desc: String) { - jmethod.visitMethodInsn(Opcodes.INVOKESPECIAL, owner, name, desc, false) - } - def invokestatic(owner: String, name: String, desc: String) { - jmethod.visitMethodInsn(Opcodes.INVOKESTATIC, owner, name, desc, false) - } - def invokeinterface(owner: String, name: String, desc: String) { - jmethod.visitMethodInsn(Opcodes.INVOKEINTERFACE, owner, name, desc, true) - } - def invokevirtual(owner: String, name: String, desc: String) { - jmethod.visitMethodInsn(Opcodes.INVOKEVIRTUAL, owner, name, desc, false) - } - - def goTo(label: asm.Label) { jmethod.visitJumpInsn(Opcodes.GOTO, label) } - def emitIF(cond: TestOp, label: asm.Label) { jmethod.visitJumpInsn(cond.opcodeIF(), label) } - def emitIF_ICMP(cond: TestOp, label: asm.Label) { jmethod.visitJumpInsn(cond.opcodeIFICMP(), label) } - def emitIF_ACMP(cond: TestOp, label: asm.Label) { - assert((cond == EQ) || (cond == NE), cond) - val opc = (if(cond == EQ) Opcodes.IF_ACMPEQ else Opcodes.IF_ACMPNE) - jmethod.visitJumpInsn(opc, label) - } - def emitIFNONNULL(label: asm.Label) { jmethod.visitJumpInsn(Opcodes.IFNONNULL, label) } - def emitIFNULL (label: asm.Label) { jmethod.visitJumpInsn(Opcodes.IFNULL, label) } - - def emitRETURN(tk: TypeKind) { - if(tk == UNIT) { jmethod.visitInsn(Opcodes.RETURN) } - else { emitTypeBased(returnOpcodes, tk) } - } - - /** Emits one of tableswitch or lookoupswitch. */ - def emitSWITCH(keys: Array[Int], branches: Array[asm.Label], defaultBranch: asm.Label, minDensity: Double) { - assert(keys.length == branches.length) - - // For empty keys, it makes sense emitting LOOKUPSWITCH with defaultBranch only. - // Similar to what javac emits for a switch statement consisting only of a default case. - if (keys.length == 0) { - jmethod.visitLookupSwitchInsn(defaultBranch, keys, branches) - return - } - - // sort `keys` by increasing key, keeping `branches` in sync. TODO FIXME use quicksort - var i = 1 - while (i < keys.length) { - var j = 1 - while (j <= keys.length - i) { - if (keys(j) < keys(j - 1)) { - val tmp = keys(j) - keys(j) = keys(j - 1) - keys(j - 1) = tmp - val tmpL = branches(j) - branches(j) = branches(j - 1) - branches(j - 1) = tmpL - } - j += 1 - } - i += 1 - } - - // check for duplicate keys to avoid "VerifyError: unsorted lookupswitch" (SI-6011) - i = 1 - while (i < keys.length) { - if(keys(i-1) == keys(i)) { - abort("duplicate keys in SWITCH, can't pick arbitrarily one of them to evict, see SI-6011.") - } - i += 1 - } - - val keyMin = keys(0) - val keyMax = keys(keys.length - 1) - - val isDenseEnough: Boolean = { - /* Calculate in long to guard against overflow. TODO what overflow??? */ - val keyRangeD: Double = (keyMax.asInstanceOf[Long] - keyMin + 1).asInstanceOf[Double] - val klenD: Double = keys.length.toDouble - val kdensity: Double = (klenD / keyRangeD) - - kdensity >= minDensity - } - - if (isDenseEnough) { - // use a table in which holes are filled with defaultBranch. - val keyRange = (keyMax - keyMin + 1) - val newBranches = new Array[asm.Label](keyRange) - var oldPos = 0 - var i = 0 - while(i < keyRange) { - val key = keyMin + i - if (keys(oldPos) == key) { - newBranches(i) = branches(oldPos) - oldPos += 1 - } else { - newBranches(i) = defaultBranch - } - i += 1 - } - assert(oldPos == keys.length, "emitSWITCH") - jmethod.visitTableSwitchInsn(keyMin, keyMax, defaultBranch, newBranches: _*) - } else { - jmethod.visitLookupSwitchInsn(defaultBranch, keys, branches) - } - } - - // internal helpers -- not part of the public API of `jcode` - // don't make private otherwise inlining will suffer - - def emitVarInsn(opc: Int, idx: Int, tk: TypeKind) { - assert((opc == Opcodes.ILOAD) || (opc == Opcodes.ISTORE), opc) - jmethod.visitVarInsn(javaType(tk).getOpcode(opc), idx) - } - - // ---------------- array load and store ---------------- - - val aloadOpcodes = { import Opcodes._; Array(AALOAD, BALOAD, SALOAD, CALOAD, IALOAD, LALOAD, FALOAD, DALOAD) } - val astoreOpcodes = { import Opcodes._; Array(AASTORE, BASTORE, SASTORE, CASTORE, IASTORE, LASTORE, FASTORE, DASTORE) } - - val returnOpcodes = { import Opcodes._; Array(ARETURN, IRETURN, IRETURN, IRETURN, IRETURN, LRETURN, FRETURN, DRETURN) } - - def emitTypeBased(opcs: Array[Int], tk: TypeKind) { - assert(tk != UNIT, tk) - val opc = { - if(tk.isRefOrArrayType) { opcs(0) } - else if(tk.isIntSizedType) { - (tk: @unchecked) match { - case BOOL | BYTE => opcs(1) - case SHORT => opcs(2) - case CHAR => opcs(3) - case INT => opcs(4) - } - } else { - (tk: @unchecked) match { - case LONG => opcs(5) - case FLOAT => opcs(6) - case DOUBLE => opcs(7) - } - } - } - jmethod.visitInsn(opc) - } - - // ---------------- primitive operations ---------------- - - val negOpcodes: Array[Int] = { import Opcodes._; Array(INEG, LNEG, FNEG, DNEG) } - val addOpcodes: Array[Int] = { import Opcodes._; Array(IADD, LADD, FADD, DADD) } - val subOpcodes: Array[Int] = { import Opcodes._; Array(ISUB, LSUB, FSUB, DSUB) } - val mulOpcodes: Array[Int] = { import Opcodes._; Array(IMUL, LMUL, FMUL, DMUL) } - val divOpcodes: Array[Int] = { import Opcodes._; Array(IDIV, LDIV, FDIV, DDIV) } - val remOpcodes: Array[Int] = { import Opcodes._; Array(IREM, LREM, FREM, DREM) } - - def emitPrimitive(opcs: Array[Int], tk: TypeKind) { - val opc = { - if(tk.isIntSizedType) { opcs(0) } - else { - (tk: @unchecked) match { - case LONG => opcs(1) - case FLOAT => opcs(2) - case DOUBLE => opcs(3) - } - } - } - jmethod.visitInsn(opc) - } - - } - - /** Invoked from genMethod() and addStaticInit() */ - def genCode(m: IMethod, - emitVars: Boolean, // this param name hides the instance-level var - isStatic: Boolean) { - - - newNormal.normalize(m) - - // ------------------------------------------------------------------------------------------------------------ - // Part 1 of genCode(): setting up one-to-one correspondence between ASM Labels and BasicBlocks `linearization` - // ------------------------------------------------------------------------------------------------------------ - - val linearization: List[BasicBlock] = linearizer.linearize(m) - if(linearization.isEmpty) { return } - - var isModuleInitialized = false - - val labels: scala.collection.Map[BasicBlock, asm.Label] = mutable.HashMap(linearization map (_ -> new asm.Label()) : _*) - - val onePastLast = new asm.Label // token for the mythical instruction past the last instruction in the method being emitted - - // maps a BasicBlock b to the Label that corresponds to b's successor in the linearization. The last BasicBlock is mapped to the onePastLast label. - val linNext: scala.collection.Map[BasicBlock, asm.Label] = { - val result = mutable.HashMap.empty[BasicBlock, asm.Label] - var rest = linearization - var prev = rest.head - rest = rest.tail - while(!rest.isEmpty) { - result += (prev -> labels(rest.head)) - prev = rest.head - rest = rest.tail - } - assert(!result.contains(prev)) - result += (prev -> onePastLast) - - result - } - - // ------------------------------------------------------------------------------------------------------------ - // Part 2 of genCode(): demarcating exception handler boundaries (visitTryCatchBlock() must be invoked before visitLabel() in genBlock()) - // ------------------------------------------------------------------------------------------------------------ - - /* Generate exception handlers for the current method. - * - * Quoting from the JVMS 4.7.3 The Code Attribute - * The items of the Code_attribute structure are as follows: - * . . . - * exception_table[] - * Each entry in the exception_table array describes one - * exception handler in the code array. The order of the handlers in - * the exception_table array is significant. - * Each exception_table entry contains the following four items: - * start_pc, end_pc: - * ... The value of end_pc either must be a valid index into - * the code array of the opcode of an instruction or must be equal to code_length, - * the length of the code array. - * handler_pc: - * The value of the handler_pc item indicates the start of the exception handler - * catch_type: - * ... If the value of the catch_type item is zero, - * this exception handler is called for all exceptions. - * This is used to implement finally - */ - def genExceptionHandlers() { - - /* Return a list of pairs of intervals where the handler is active. - * Each interval is closed on both ends, ie. inclusive both in the left and right endpoints: [start, end]. - * Preconditions: - * - e.covered non-empty - * Postconditions for the result: - * - always non-empty - * - intervals are sorted as per `linearization` - * - the argument's `covered` blocks have been grouped into maximally contiguous intervals, - * ie. between any two intervals in the result there is a non-empty gap. - * - each of the `covered` blocks in the argument is contained in some interval in the result - */ - def intervals(e: ExceptionHandler): List[BlockInteval] = { - assert(e.covered.nonEmpty, e) - var result: List[BlockInteval] = Nil - var rest = linearization - - // find intervals - while(!rest.isEmpty) { - // find interval start - var start: BasicBlock = null - while(!rest.isEmpty && (start eq null)) { - if(e.covered(rest.head)) { start = rest.head } - rest = rest.tail - } - if(start ne null) { - // find interval end - var end = start // for the time being - while(!rest.isEmpty && (e.covered(rest.head))) { - end = rest.head - rest = rest.tail - } - result = BlockInteval(start, end) :: result - } - } - - assert(result.nonEmpty, e) - - result - } - - /* TODO test/files/run/exceptions-2.scala displays an ExceptionHandler.covered that contains - * blocks not in the linearization (dead-code?). Is that well-formed or not? - * For now, we ignore those blocks (after all, that's what `genBlocks(linearization)` in effect does). - */ - for (e <- this.method.exh) { - val ignore: Set[BasicBlock] = (e.covered filterNot { b => linearization contains b } ) - // TODO someday assert(ignore.isEmpty, "an ExceptionHandler.covered contains blocks not in the linearization (dead-code?)") - if(ignore.nonEmpty) { - e.covered = e.covered filterNot ignore - } - } - - // an ExceptionHandler lacking covered blocks doesn't get an entry in the Exceptions table. - // TODO in that case, ExceptionHandler.cls doesn't go through javaName(). What if cls is an inner class? - for (e <- this.method.exh ; if e.covered.nonEmpty ; p <- intervals(e)) { - debuglog("Adding exception handler " + e + "at block: " + e.startBlock + " for " + method + - " from: " + p.start + " to: " + p.end + " catching: " + e.cls) - val cls: String = if (e.cls == NoSymbol || e.cls == ThrowableClass) null - else javaName(e.cls) - jmethod.visitTryCatchBlock(labels(p.start), linNext(p.end), labels(e.startBlock), cls) - } - } // end of genCode()'s genExceptionHandlers() - - if (m.exh.nonEmpty) { genExceptionHandlers() } - - // ------------------------------------------------------------------------------------------------------------ - // Part 3 of genCode(): "Infrastructure" to later emit debug info for local variables and method params (LocalVariablesTable bytecode attribute). - // ------------------------------------------------------------------------------------------------------------ - - case class LocVarEntry(local: Local, start: asm.Label, end: asm.Label) // start is inclusive while end exclusive. - - case class Interval(lstart: asm.Label, lend: asm.Label) { - final def start = lstart.getOffset - final def end = lend.getOffset - - def precedes(that: Interval): Boolean = { this.end < that.start } - - def overlaps(that: Interval): Boolean = { !(this.precedes(that) || that.precedes(this)) } - - def mergeWith(that: Interval): Interval = { - val newStart = if(this.start <= that.start) this.lstart else that.lstart - val newEnd = if(this.end <= that.end) that.lend else this.lend - Interval(newStart, newEnd) - } - - def repOK: Boolean = { start <= end } - - } - - /** Track those instruction ranges where certain locals are in scope. Used to later emit the LocalVariableTable attribute (JVMS 4.7.13) */ - object scoping { - - private val pending = mutable.Map.empty[Local, mutable.Stack[Label]] - private var seen: List[LocVarEntry] = Nil - - private def fuse(ranges: List[Interval], added: Interval): List[Interval] = { - assert(added.repOK, added) - if(ranges.isEmpty) { return List(added) } - // precond: ranges is sorted by increasing start - var fused: List[Interval] = Nil - var done = false - var rest = ranges - while(!done && rest.nonEmpty) { - val current = rest.head - assert(current.repOK, current) - rest = rest.tail - if(added precedes current) { - fused = fused ::: ( added :: current :: rest ) - done = true - } else if(current overlaps added) { - fused = fused ::: ( added.mergeWith(current) :: rest ) - done = true - } - } - if(!done) { fused = fused ::: List(added) } - assert(repOK(fused), fused) - - fused - } - - def pushScope(lv: Local, start: Label) { - val st = pending.getOrElseUpdate(lv, mutable.Stack.empty[Label]) - st.push(start) - } - def popScope(lv: Local, end: Label, iPos: Position) { - pending.get(lv) match { - case Some(st) if st.nonEmpty => - val start = st.pop() - seen ::= LocVarEntry(lv, start, end) - case _ => - // TODO SI-6049 track down the cause for these. - devWarning(s"$iPos: Visited SCOPE_EXIT before visiting corresponding SCOPE_ENTER. SI-6191") - } - } - - def getMerged(): scala.collection.Map[Local, List[Interval]] = { - // TODO should but isn't: unbalanced start(s) of scope(s) - val shouldBeEmpty = pending filter { p => val (_, st) = p; st.nonEmpty } - val merged = mutable.Map[Local, List[Interval]]() - def addToMerged(lv: Local, start: Label, end: Label) { - val intv = Interval(start, end) - merged(lv) = if (merged contains lv) fuse(merged(lv), intv) else intv :: Nil - } - for(LocVarEntry(lv, start, end) <- seen) { addToMerged(lv, start, end) } - - /* for each var with unbalanced start(s) of scope(s): - (a) take the earliest start (among unbalanced and balanced starts) - (b) take the latest end (onePastLast if none available) - (c) merge the thus made-up interval - */ - for((k, st) <- shouldBeEmpty) { - var start = st.toList.sortBy(_.getOffset).head - if(merged.isDefinedAt(k)) { - val balancedStart = merged(k).head.lstart - if(balancedStart.getOffset < start.getOffset) { - start = balancedStart - } - } - val endOpt: Option[Label] = for(ranges <- merged.get(k)) yield ranges.last.lend - val end = endOpt.getOrElse(onePastLast) - addToMerged(k, start, end) - } - - merged - } - - private def repOK(fused: List[Interval]): Boolean = { - fused match { - case Nil => true - case h :: Nil => h.repOK - case h :: n :: rest => - h.repOK && h.precedes(n) && !h.overlaps(n) && repOK(n :: rest) - } - } - - } - - def genLocalVariableTable() { - // adding `this` and method params. - if (!isStatic) { - jmethod.visitLocalVariable("this", thisDescr, null, labels(m.startBlock), onePastLast, 0) - } - for(lv <- m.params) { - jmethod.visitLocalVariable(javaName(lv.sym), descriptor(lv.kind), null, labels(m.startBlock), onePastLast, indexOf(lv)) - } - // adding non-param locals - var anonCounter = 0 - var fltnd: List[Tuple3[String, Local, Interval]] = Nil - for((local, ranges) <- scoping.getMerged()) { - var name = javaName(local.sym) - if (name == null) { - anonCounter += 1 - name = "<anon" + anonCounter + ">" - } - for(intrvl <- ranges) { - fltnd ::= (name, local, intrvl) - } - } - // quest for deterministic output that Map.toList doesn't provide (so that ant test.stability doesn't complain). - val srtd = fltnd.sortBy { kr => - val (name: String, _, intrvl: Interval) = kr - - (intrvl.start, intrvl.end - intrvl.start, name) // ie sort by (start, length, name) - } - - for((name, local, Interval(start, end)) <- srtd) { - jmethod.visitLocalVariable(name, descriptor(local.kind), null, start, end, indexOf(local)) - } - // "There may be no more than one LocalVariableTable attribute per local variable in the Code attribute" - } - - // ------------------------------------------------------------------------------------------------------------ - // Part 4 of genCode(): Bookkeeping (to later emit debug info) of association between line-number and instruction position. - // ------------------------------------------------------------------------------------------------------------ - - case class LineNumberEntry(line: Int, start: asm.Label) - var lastLineNr: Int = -1 - var lnEntries: List[LineNumberEntry] = Nil - - // ------------------------------------------------------------------------------------------------------------ - // Part 5 of genCode(): "Utilities" to emit code proper (most prominently: genBlock()). - // ------------------------------------------------------------------------------------------------------------ - - var nextBlock: BasicBlock = linearization.head - - def genBlocks(l: List[BasicBlock]): Unit = l match { - case Nil => () - case x :: Nil => nextBlock = null; genBlock(x) - case x :: y :: ys => nextBlock = y; genBlock(x); genBlocks(y :: ys) - } - - def genCallMethod(call: CALL_METHOD) { - val CALL_METHOD(method, style) = call - val siteSymbol = clasz.symbol - val hostSymbol = call.hostClass - val methodOwner = method.owner - // info calls so that types are up to date; erasure may add lateINTERFACE to traits - hostSymbol.info ; methodOwner.info - - def needsInterfaceCall(sym: Symbol) = ( - sym.isInterface - || sym.isJavaDefined && sym.isNonBottomSubClass(ClassfileAnnotationClass) - ) - // whether to reference the type of the receiver or - // the type of the method owner - val useMethodOwner = ( - style != Dynamic - || hostSymbol.isBottomClass - || methodOwner == ObjectClass - ) - val receiver = if (useMethodOwner) methodOwner else hostSymbol - val jowner = javaName(receiver) - val jname = javaName(method) - val jtype = javaType(method).getDescriptor() - - def dbg(invoke: String) { - debuglog("%s %s %s.%s:%s".format(invoke, receiver.accessString, jowner, jname, jtype)) - } - - def initModule() { - // we initialize the MODULE$ field immediately after the super ctor - if (isStaticModule(siteSymbol) && !isModuleInitialized && - jMethodName == INSTANCE_CONSTRUCTOR_NAME && - jname == INSTANCE_CONSTRUCTOR_NAME) { - isModuleInitialized = true - jmethod.visitVarInsn(asm.Opcodes.ALOAD, 0) - jmethod.visitFieldInsn(asm.Opcodes.PUTSTATIC, thisName, strMODULE_INSTANCE_FIELD, thisDescr) - } - } - - style match { - case Static(true) => dbg("invokespecial"); jcode.invokespecial (jowner, jname, jtype) - case Static(false) => dbg("invokestatic"); jcode.invokestatic (jowner, jname, jtype) - case Dynamic if needsInterfaceCall(receiver) => dbg("invokinterface"); jcode.invokeinterface(jowner, jname, jtype) - case Dynamic => dbg("invokevirtual"); jcode.invokevirtual (jowner, jname, jtype) - case SuperCall(_) => - dbg("invokespecial") - jcode.invokespecial(jowner, jname, jtype) - initModule() - } - } // end of genCode()'s genCallMethod() - - def genBlock(b: BasicBlock) { - jmethod.visitLabel(labels(b)) - - debuglog("Generating code for block: " + b) - - // val lastInstr = b.lastInstruction - - for (instr <- b) { - - if(instr.pos.isDefined) { - val iPos = instr.pos - val currentLineNr = iPos.line - val skip = (currentLineNr == lastLineNr) // if(iPos.isRange) iPos.sameRange(lastPos) else - if(!skip) { - lastLineNr = currentLineNr - val lineLab = new asm.Label - jmethod.visitLabel(lineLab) - lnEntries ::= LineNumberEntry(iPos.finalPosition.line, lineLab) - } - } - - genInstr(instr, b) - - } - - } - - def genInstr(instr: Instruction, b: BasicBlock) { - import asm.Opcodes - (instr.category: @scala.annotation.switch) match { - - - case icodes.localsCat => - def genLocalInstr() = (instr: @unchecked) match { - case THIS(_) => jmethod.visitVarInsn(Opcodes.ALOAD, 0) - case LOAD_LOCAL(local) => jcode.load(indexOf(local), local.kind) - case STORE_LOCAL(local) => jcode.store(indexOf(local), local.kind) - case STORE_THIS(_) => - // this only works for impl classes because the self parameter comes first - // in the method signature. If that changes, this code has to be revisited. - jmethod.visitVarInsn(Opcodes.ASTORE, 0) - - case SCOPE_ENTER(lv) => - // locals removed by closelim (via CopyPropagation) may have left behind SCOPE_ENTER, SCOPE_EXIT that are to be ignored - val relevant = (!lv.sym.isSynthetic && m.locals.contains(lv)) - if (relevant) { // TODO check: does GenICode emit SCOPE_ENTER, SCOPE_EXIT for synthetic vars? - // this label will have DEBUG bit set in its flags (ie ASM ignores it for dataflow purposes) - // similarly, these labels aren't tracked in the `labels` map. - val start = new asm.Label - jmethod.visitLabel(start) - scoping.pushScope(lv, start) - } - - case SCOPE_EXIT(lv) => - val relevant = (!lv.sym.isSynthetic && m.locals.contains(lv)) - if (relevant) { - // this label will have DEBUG bit set in its flags (ie ASM ignores it for dataflow purposes) - // similarly, these labels aren't tracked in the `labels` map. - val end = new asm.Label - jmethod.visitLabel(end) - scoping.popScope(lv, end, instr.pos) - } - } - genLocalInstr() - - case icodes.stackCat => - def genStackInstr() = (instr: @unchecked) match { - - case LOAD_MODULE(module) => - // assert(module.isModule, "Expected module: " + module) - debuglog("generating LOAD_MODULE for: " + module + " flags: " + module.flagString) - def inStaticMethod = this.method != null && this.method.symbol.isStaticMember - if (clasz.symbol == module.moduleClass && jMethodName != nme.readResolve.toString && !inStaticMethod) { - jmethod.visitVarInsn(Opcodes.ALOAD, 0) - } else { - jmethod.visitFieldInsn( - Opcodes.GETSTATIC, - javaName(module) /* + "$" */ , - strMODULE_INSTANCE_FIELD, - descriptor(module)) - } - - case DROP(kind) => emit(if (kind.isWideType) Opcodes.POP2 else Opcodes.POP) - - case DUP(kind) => emit(if (kind.isWideType) Opcodes.DUP2 else Opcodes.DUP) - - case LOAD_EXCEPTION(_) => () - } - genStackInstr() - - case icodes.constCat => genConstant(jmethod, instr.asInstanceOf[CONSTANT].constant) - - case icodes.arilogCat => genPrimitive(instr.asInstanceOf[CALL_PRIMITIVE].primitive, instr.pos) - - case icodes.castsCat => - def genCastInstr() = (instr: @unchecked) match { - - case IS_INSTANCE(tpe) => - val jtyp: asm.Type = - tpe match { - case REFERENCE(cls) => asm.Type.getObjectType(javaName(cls)) - case ARRAY(elem) => javaArrayType(javaType(elem)) - case _ => abort("Unknown reference type in IS_INSTANCE: " + tpe) - } - jmethod.visitTypeInsn(Opcodes.INSTANCEOF, jtyp.getInternalName) - - case CHECK_CAST(tpe) => - tpe match { - - case REFERENCE(cls) => - if (cls != ObjectClass) { // No need to checkcast for Objects - jmethod.visitTypeInsn(Opcodes.CHECKCAST, javaName(cls)) - } - - case ARRAY(elem) => - val iname = javaArrayType(javaType(elem)).getInternalName - jmethod.visitTypeInsn(Opcodes.CHECKCAST, iname) - - case _ => abort("Unknown reference type in IS_INSTANCE: " + tpe) - } - - } - genCastInstr() - - case icodes.objsCat => - def genObjsInstr() = (instr: @unchecked) match { - case BOX(kind) => - val MethodNameAndType(mname, mdesc) = jBoxTo(kind) - jcode.invokestatic(BoxesRunTime, mname, mdesc) - - case UNBOX(kind) => - val MethodNameAndType(mname, mdesc) = jUnboxTo(kind) - jcode.invokestatic(BoxesRunTime, mname, mdesc) - - case NEW(REFERENCE(cls)) => - val className = javaName(cls) - jmethod.visitTypeInsn(Opcodes.NEW, className) - - case MONITOR_ENTER() => emit(Opcodes.MONITORENTER) - case MONITOR_EXIT() => emit(Opcodes.MONITOREXIT) - } - genObjsInstr() - - case icodes.fldsCat => - def genFldsInstr() = (instr: @unchecked) match { - - case lf @ LOAD_FIELD(field, isStatic) => - val owner = javaName(lf.hostClass) - debuglog("LOAD_FIELD with owner: " + owner + " flags: " + field.owner.flagString) - val fieldJName = javaName(field) - val fieldDescr = descriptor(field) - val opc = if (isStatic) Opcodes.GETSTATIC else Opcodes.GETFIELD - jmethod.visitFieldInsn(opc, owner, fieldJName, fieldDescr) - - case STORE_FIELD(field, isStatic) => - val owner = javaName(field.owner) - val fieldJName = javaName(field) - val fieldDescr = descriptor(field) - val opc = if (isStatic) Opcodes.PUTSTATIC else Opcodes.PUTFIELD - jmethod.visitFieldInsn(opc, owner, fieldJName, fieldDescr) - - } - genFldsInstr() - - case icodes.mthdsCat => - def genMethodsInstr() = (instr: @unchecked) match { - - /* Special handling to access native Array.clone() */ - case call @ CALL_METHOD(definitions.Array_clone, Dynamic) => - val target: String = javaType(call.targetTypeKind).getInternalName - jcode.invokevirtual(target, "clone", mdesc_arrayClone) - - case call @ CALL_METHOD(method, style) => genCallMethod(call) - - } - genMethodsInstr() - - case icodes.arraysCat => - def genArraysInstr() = (instr: @unchecked) match { - case LOAD_ARRAY_ITEM(kind) => jcode.aload(kind) - case STORE_ARRAY_ITEM(kind) => jcode.astore(kind) - case CREATE_ARRAY(elem, 1) => jcode newarray elem - case CREATE_ARRAY(elem, dims) => jmethod.visitMultiANewArrayInsn(descriptor(ArrayN(elem, dims)), dims) - } - genArraysInstr() - - case icodes.jumpsCat => - def genJumpInstr() = (instr: @unchecked) match { - - case sw @ SWITCH(tagss, branches) => - assert(branches.length == tagss.length + 1, sw) - val flatSize = sw.flatTagsCount - val flatKeys = new Array[Int](flatSize) - val flatBranches = new Array[asm.Label](flatSize) - - var restTagss = tagss - var restBranches = branches - var k = 0 // ranges over flatKeys and flatBranches - while (restTagss.nonEmpty) { - val currLabel = labels(restBranches.head) - for (cTag <- restTagss.head) { - flatKeys(k) = cTag - flatBranches(k) = currLabel - k += 1 - } - restTagss = restTagss.tail - restBranches = restBranches.tail - } - val defaultLabel = labels(restBranches.head) - assert(restBranches.tail.isEmpty) - debuglog("Emitting SWITCH:\ntags: " + tagss + "\nbranches: " + branches) - jcode.emitSWITCH(flatKeys, flatBranches, defaultLabel, MIN_SWITCH_DENSITY) - - case JUMP(whereto) => - if (nextBlock != whereto) - jcode goTo labels(whereto) - // SI-6102: Determine whether eliding this JUMP results in an empty range being covered by some EH. - // If so, emit a NOP in place of the elided JUMP, to avoid "java.lang.ClassFormatError: Illegal exception table range" - else if (newNormal.isJumpOnly(b) && m.exh.exists(eh => eh.covers(b))) { - devWarning("Had a jump only block that wasn't collapsed") - emit(asm.Opcodes.NOP) - } - - case CJUMP(success, failure, cond, kind) => - if (kind.isIntSizedType) { // BOOL, BYTE, CHAR, SHORT, or INT - if (nextBlock == success) { - jcode.emitIF_ICMP(cond.negate(), labels(failure)) - // .. and fall through to success label - } else { - jcode.emitIF_ICMP(cond, labels(success)) - if (nextBlock != failure) { jcode goTo labels(failure) } - } - } else if (kind.isRefOrArrayType) { // REFERENCE(_) | ARRAY(_) - if (nextBlock == success) { - jcode.emitIF_ACMP(cond.negate(), labels(failure)) - // .. and fall through to success label - } else { - jcode.emitIF_ACMP(cond, labels(success)) - if (nextBlock != failure) { jcode goTo labels(failure) } - } - } else { - (kind: @unchecked) match { - case LONG => emit(Opcodes.LCMP) - case FLOAT => - if (cond == LT || cond == LE) emit(Opcodes.FCMPG) - else emit(Opcodes.FCMPL) - case DOUBLE => - if (cond == LT || cond == LE) emit(Opcodes.DCMPG) - else emit(Opcodes.DCMPL) - } - if (nextBlock == success) { - jcode.emitIF(cond.negate(), labels(failure)) - // .. and fall through to success label - } else { - jcode.emitIF(cond, labels(success)) - if (nextBlock != failure) { jcode goTo labels(failure) } - } - } - - case CZJUMP(success, failure, cond, kind) => - if (kind.isIntSizedType) { // BOOL, BYTE, CHAR, SHORT, or INT - if (nextBlock == success) { - jcode.emitIF(cond.negate(), labels(failure)) - } else { - jcode.emitIF(cond, labels(success)) - if (nextBlock != failure) { jcode goTo labels(failure) } - } - } else if (kind.isRefOrArrayType) { // REFERENCE(_) | ARRAY(_) - val Success = success - val Failure = failure - // @unchecked because references aren't compared with GT, GE, LT, LE. - ((cond, nextBlock): @unchecked) match { - case (EQ, Success) => jcode emitIFNONNULL labels(failure) - case (NE, Failure) => jcode emitIFNONNULL labels(success) - case (EQ, Failure) => jcode emitIFNULL labels(success) - case (NE, Success) => jcode emitIFNULL labels(failure) - case (EQ, _) => - jcode emitIFNULL labels(success) - jcode goTo labels(failure) - case (NE, _) => - jcode emitIFNONNULL labels(success) - jcode goTo labels(failure) - } - } else { - (kind: @unchecked) match { - case LONG => - emit(Opcodes.LCONST_0) - emit(Opcodes.LCMP) - case FLOAT => - emit(Opcodes.FCONST_0) - if (cond == LT || cond == LE) emit(Opcodes.FCMPG) - else emit(Opcodes.FCMPL) - case DOUBLE => - emit(Opcodes.DCONST_0) - if (cond == LT || cond == LE) emit(Opcodes.DCMPG) - else emit(Opcodes.DCMPL) - } - if (nextBlock == success) { - jcode.emitIF(cond.negate(), labels(failure)) - } else { - jcode.emitIF(cond, labels(success)) - if (nextBlock != failure) { jcode goTo labels(failure) } - } - } - - } - genJumpInstr() - - case icodes.retCat => - def genRetInstr() = (instr: @unchecked) match { - case RETURN(kind) => jcode emitRETURN kind - case THROW(_) => emit(Opcodes.ATHROW) - } - genRetInstr() - } - } - - /* - * Emits one or more conversion instructions based on the types given as arguments. - * - * @param from The type of the value to be converted into another type. - * @param to The type the value will be converted into. - */ - def emitT2T(from: TypeKind, to: TypeKind) { - assert(isNonUnitValueTK(from) && isNonUnitValueTK(to), s"Cannot emit primitive conversion from $from to $to") - - def pickOne(opcs: Array[Int]) { - val chosen = (to: @unchecked) match { - case BYTE => opcs(0) - case SHORT => opcs(1) - case CHAR => opcs(2) - case INT => opcs(3) - case LONG => opcs(4) - case FLOAT => opcs(5) - case DOUBLE => opcs(6) - } - if(chosen != -1) { emit(chosen) } - } - - if(from == to) { return } - // the only conversion involving BOOL that is allowed is (BOOL -> BOOL) - assert(from != BOOL && to != BOOL, s"inconvertible types : $from -> $to") - - if(from.isIntSizedType) { // BYTE, CHAR, SHORT, and INT. (we're done with BOOL already) - - val fromByte = { import asm.Opcodes._; Array( -1, -1, I2C, -1, I2L, I2F, I2D) } // do nothing for (BYTE -> SHORT) and for (BYTE -> INT) - val fromChar = { import asm.Opcodes._; Array(I2B, I2S, -1, -1, I2L, I2F, I2D) } // for (CHAR -> INT) do nothing - val fromShort = { import asm.Opcodes._; Array(I2B, -1, I2C, -1, I2L, I2F, I2D) } // for (SHORT -> INT) do nothing - val fromInt = { import asm.Opcodes._; Array(I2B, I2S, I2C, -1, I2L, I2F, I2D) } - - (from: @unchecked) match { - case BYTE => pickOne(fromByte) - case SHORT => pickOne(fromShort) - case CHAR => pickOne(fromChar) - case INT => pickOne(fromInt) - } - - } else { // FLOAT, LONG, DOUBLE - - (from: @unchecked) match { - case FLOAT => - import asm.Opcodes.{ F2L, F2D, F2I } - (to: @unchecked) match { - case LONG => emit(F2L) - case DOUBLE => emit(F2D) - case _ => emit(F2I); emitT2T(INT, to) - } - - case LONG => - import asm.Opcodes.{ L2F, L2D, L2I } - (to: @unchecked) match { - case FLOAT => emit(L2F) - case DOUBLE => emit(L2D) - case _ => emit(L2I); emitT2T(INT, to) - } - - case DOUBLE => - import asm.Opcodes.{ D2L, D2F, D2I } - (to: @unchecked) match { - case FLOAT => emit(D2F) - case LONG => emit(D2L) - case _ => emit(D2I); emitT2T(INT, to) - } - } - } - } // end of genCode()'s emitT2T() - - def genPrimitive(primitive: Primitive, pos: Position) { - - import asm.Opcodes - - primitive match { - - case Negation(kind) => jcode.neg(kind) - - case Arithmetic(op, kind) => - def genArith() = { - op match { - - case ADD => jcode.add(kind) - case SUB => jcode.sub(kind) - case MUL => jcode.mul(kind) - case DIV => jcode.div(kind) - case REM => jcode.rem(kind) - - case NOT => - if(kind.isIntSizedType) { - emit(Opcodes.ICONST_M1) - emit(Opcodes.IXOR) - } else if(kind == LONG) { - jmethod.visitLdcInsn(new java.lang.Long(-1)) - jmethod.visitInsn(Opcodes.LXOR) - } else { - abort("Impossible to negate an " + kind) - } - - case _ => - abort("Unknown arithmetic primitive " + primitive) - } - } - genArith() - - // TODO Logical's 2nd elem should be declared ValueTypeKind, to better approximate its allowed values (isIntSized, its comments appears to convey) - // TODO GenICode uses `toTypeKind` to define that elem, `toValueTypeKind` would be needed instead. - // TODO How about adding some asserts to Logical and similar ones to capture the remaining constraint (UNIT not allowed). - case Logical(op, kind) => - def genLogical() = op match { - case AND => - kind match { - case LONG => emit(Opcodes.LAND) - case INT => emit(Opcodes.IAND) - case _ => - emit(Opcodes.IAND) - if (kind != BOOL) { emitT2T(INT, kind) } - } - case OR => - kind match { - case LONG => emit(Opcodes.LOR) - case INT => emit(Opcodes.IOR) - case _ => - emit(Opcodes.IOR) - if (kind != BOOL) { emitT2T(INT, kind) } - } - case XOR => - kind match { - case LONG => emit(Opcodes.LXOR) - case INT => emit(Opcodes.IXOR) - case _ => - emit(Opcodes.IXOR) - if (kind != BOOL) { emitT2T(INT, kind) } - } - } - genLogical() - - case Shift(op, kind) => - def genShift() = op match { - case LSL => - kind match { - case LONG => emit(Opcodes.LSHL) - case INT => emit(Opcodes.ISHL) - case _ => - emit(Opcodes.ISHL) - emitT2T(INT, kind) - } - case ASR => - kind match { - case LONG => emit(Opcodes.LSHR) - case INT => emit(Opcodes.ISHR) - case _ => - emit(Opcodes.ISHR) - emitT2T(INT, kind) - } - case LSR => - kind match { - case LONG => emit(Opcodes.LUSHR) - case INT => emit(Opcodes.IUSHR) - case _ => - emit(Opcodes.IUSHR) - emitT2T(INT, kind) - } - } - genShift() - - case Comparison(op, kind) => - def genCompare() = op match { - case CMP => - (kind: @unchecked) match { - case LONG => emit(Opcodes.LCMP) - } - case CMPL => - (kind: @unchecked) match { - case FLOAT => emit(Opcodes.FCMPL) - case DOUBLE => emit(Opcodes.DCMPL) - } - case CMPG => - (kind: @unchecked) match { - case FLOAT => emit(Opcodes.FCMPG) - case DOUBLE => emit(Opcodes.DCMPL) // TODO bug? why not DCMPG? http://docs.oracle.com/javase/specs/jvms/se6/html/Instructions2.doc3.html - - } - } - genCompare() - - case Conversion(src, dst) => - debuglog("Converting from: " + src + " to: " + dst) - emitT2T(src, dst) - - case ArrayLength(_) => emit(Opcodes.ARRAYLENGTH) - - case StartConcat => - jmethod.visitTypeInsn(Opcodes.NEW, StringBuilderClassName) - jmethod.visitInsn(Opcodes.DUP) - jcode.invokespecial( - StringBuilderClassName, - INSTANCE_CONSTRUCTOR_NAME, - mdesc_arglessvoid - ) - - case StringConcat(el) => - val jtype = el match { - case REFERENCE(_) | ARRAY(_) => JAVA_LANG_OBJECT - case _ => javaType(el) - } - jcode.invokevirtual( - StringBuilderClassName, - "append", - asm.Type.getMethodDescriptor(StringBuilderType, Array(jtype): _*) - ) - - case EndConcat => - jcode.invokevirtual(StringBuilderClassName, "toString", mdesc_toString) - - case _ => abort("Unimplemented primitive " + primitive) - } - } // end of genCode()'s genPrimitive() - - // ------------------------------------------------------------------------------------------------------------ - // Part 6 of genCode(): the executable part of genCode() starts here. - // ------------------------------------------------------------------------------------------------------------ - - genBlocks(linearization) - - jmethod.visitLabel(onePastLast) - - if(emitLines) { - for(LineNumberEntry(line, start) <- lnEntries.sortBy(_.start.getOffset)) { jmethod.visitLineNumber(line, start) } - } - if(emitVars) { genLocalVariableTable() } - - } // end of BytecodeGenerator.genCode() - - - ////////////////////// local vars /////////////////////// - - def sizeOf(k: TypeKind): Int = if(k.isWideType) 2 else 1 - - final def indexOf(local: Local): Int = { - assert(local.index >= 0, "Invalid index for: " + local + "{" + local.## + "}: ") - local.index - } - - /** - * Compute the indexes of each local variable of the given method. - * *Does not assume the parameters come first!* - */ - def computeLocalVarsIndex(m: IMethod) { - var idx = if (m.symbol.isStaticMember) 0 else 1 - - for (l <- m.params) { - debuglog("Index value for " + l + "{" + l.## + "}: " + idx) - l.index = idx - idx += sizeOf(l.kind) - } - - for (l <- m.locals if !l.arg) { - debuglog("Index value for " + l + "{" + l.## + "}: " + idx) - l.index = idx - idx += sizeOf(l.kind) - } - } - - } // end of class JPlainBuilder - - - /** builder of mirror classes */ - class JMirrorBuilder(bytecodeWriter: BytecodeWriter, needsOutfile: Boolean) extends JCommonBuilder(bytecodeWriter, needsOutfile) { - - private var cunit: CompilationUnit = _ - def getCurrentCUnit(): CompilationUnit = cunit - - /** Generate a mirror class for a top-level module. A mirror class is a class - * containing only static methods that forward to the corresponding method - * on the MODULE instance of the given Scala object. It will only be - * generated if there is no companion class: if there is, an attempt will - * instead be made to add the forwarder methods to the companion class. - */ - def genMirrorClass(modsym: Symbol, cunit: CompilationUnit) { - assert(modsym.companionClass == NoSymbol, modsym) - innerClassBuffer.clear() - this.cunit = cunit - val moduleName = javaName(modsym) // + "$" - val mirrorName = moduleName.substring(0, moduleName.length() - 1) - - val flags = (asm.Opcodes.ACC_SUPER | asm.Opcodes.ACC_PUBLIC | asm.Opcodes.ACC_FINAL) - val mirrorClass = createJClass(flags, - mirrorName, - null /* no java-generic-signature */, - JAVA_LANG_OBJECT.getInternalName, - EMPTY_STRING_ARRAY) - - log(s"Dumping mirror class for '$mirrorName'") - - // typestate: entering mode with valid call sequences: - // [ visitSource ] [ visitOuterClass ] ( visitAnnotation | visitAttribute )* - - if(emitSource) { - mirrorClass.visitSource("" + cunit.source, - null /* SourceDebugExtension */) - } - - val ssa = getAnnotPickle(mirrorName, modsym.companionSymbol) - mirrorClass.visitAttribute(if(ssa.isDefined) pickleMarkerLocal else pickleMarkerForeign) - emitAnnotations(mirrorClass, modsym.annotations ++ ssa) - - // typestate: entering mode with valid call sequences: - // ( visitInnerClass | visitField | visitMethod )* visitEnd - - addForwarders(isRemote(modsym), mirrorClass, mirrorName, modsym) - - addInnerClasses(modsym, mirrorClass, isMirror = true) - mirrorClass.visitEnd() - writeIfNotTooBig("" + modsym.name, mirrorName, mirrorClass, modsym) - } - } // end of class JMirrorBuilder - - - /** builder of bean info classes */ - class JBeanInfoBuilder(bytecodeWriter: BytecodeWriter, needsOutfile: Boolean) extends JBuilder(bytecodeWriter, needsOutfile) { - - /** - * Generate a bean info class that describes the given class. - * - * @author Ross Judson (ross.judson@soletta.com) - */ - def genBeanInfoClass(clasz: IClass) { - - // val BeanInfoSkipAttr = definitions.getRequiredClass("scala.beans.BeanInfoSkip") - // val BeanDisplayNameAttr = definitions.getRequiredClass("scala.beans.BeanDisplayName") - // val BeanDescriptionAttr = definitions.getRequiredClass("scala.beans.BeanDescription") - // val description = c.symbol getAnnotation BeanDescriptionAttr - // informProgress(description.toString) - innerClassBuffer.clear() - - val flags = mkFlags( - javaFlags(clasz.symbol), - if(isDeprecated(clasz.symbol)) asm.Opcodes.ACC_DEPRECATED else 0 // ASM pseudo access flag - ) - - val beanInfoName = (javaName(clasz.symbol) + "BeanInfo") - val beanInfoClass = createJClass( - flags, - beanInfoName, - null, // no java-generic-signature - "scala/beans/ScalaBeanInfo", - EMPTY_STRING_ARRAY - ) - - // beanInfoClass typestate: entering mode with valid call sequences: - // [ visitSource ] [ visitOuterClass ] ( visitAnnotation | visitAttribute )* - - beanInfoClass.visitSource( - clasz.cunit.source.toString, - null /* SourceDebugExtension */ - ) - - var fieldList = List[String]() - - for (f <- clasz.fields if f.symbol.hasGetter; - g = f.symbol.getterIn(clasz.symbol); - s = f.symbol.setterIn(clasz.symbol) - if g.isPublic && !(f.symbol.name startsWith "$") - ) { - // inserting $outer breaks the bean - fieldList = javaName(f.symbol) :: javaName(g) :: (if (s != NoSymbol) javaName(s) else null) :: fieldList - } - - val methodList: List[String] = - for (m <- clasz.methods - if !m.symbol.isConstructor && - m.symbol.isPublic && - !(m.symbol.name startsWith "$") && - !m.symbol.isGetter && - !m.symbol.isSetter) - yield javaName(m.symbol) - - // beanInfoClass typestate: entering mode with valid call sequences: - // ( visitInnerClass | visitField | visitMethod )* visitEnd - - val constructor = beanInfoClass.visitMethod( - asm.Opcodes.ACC_PUBLIC, - INSTANCE_CONSTRUCTOR_NAME, - mdesc_arglessvoid, - null, // no java-generic-signature - EMPTY_STRING_ARRAY // no throwable exceptions - ) - - // constructor typestate: entering mode with valid call sequences: - // [ visitAnnotationDefault ] ( visitAnnotation | visitParameterAnnotation | visitAttribute )* - - val stringArrayJType: asm.Type = javaArrayType(JAVA_LANG_STRING) - val conJType: asm.Type = - asm.Type.getMethodType( - asm.Type.VOID_TYPE, - Array(javaType(ClassClass), stringArrayJType, stringArrayJType): _* - ) - - def push(lst: List[String]) { - var fi = 0 - for (f <- lst) { - constructor.visitInsn(asm.Opcodes.DUP) - constructor.visitLdcInsn(new java.lang.Integer(fi)) - if (f == null) { constructor.visitInsn(asm.Opcodes.ACONST_NULL) } - else { constructor.visitLdcInsn(f) } - constructor.visitInsn(JAVA_LANG_STRING.getOpcode(asm.Opcodes.IASTORE)) - fi += 1 - } - } - - // constructor typestate: entering mode with valid call sequences: - // [ visitCode ( visitFrame | visitXInsn | visitLabel | visitTryCatchBlock | visitLocalVariable | visitLineNumber )* visitMaxs ] visitEnd - - constructor.visitCode() - - constructor.visitVarInsn(asm.Opcodes.ALOAD, 0) - // push the class - constructor.visitLdcInsn(javaType(clasz.symbol)) - - // push the string array of field information - constructor.visitLdcInsn(new java.lang.Integer(fieldList.length)) - constructor.visitTypeInsn(asm.Opcodes.ANEWARRAY, JAVA_LANG_STRING.getInternalName) - push(fieldList) - - // push the string array of method information - constructor.visitLdcInsn(new java.lang.Integer(methodList.length)) - constructor.visitTypeInsn(asm.Opcodes.ANEWARRAY, JAVA_LANG_STRING.getInternalName) - push(methodList) - - // invoke the superclass constructor, which will do the - // necessary java reflection and create Method objects. - constructor.visitMethodInsn(asm.Opcodes.INVOKESPECIAL, "scala/beans/ScalaBeanInfo", INSTANCE_CONSTRUCTOR_NAME, conJType.getDescriptor, false) - constructor.visitInsn(asm.Opcodes.RETURN) - - constructor.visitMaxs(0, 0) // just to follow protocol, dummy arguments - constructor.visitEnd() - - addInnerClasses(clasz.symbol, beanInfoClass) - beanInfoClass.visitEnd() - - writeIfNotTooBig("BeanInfo ", beanInfoName, beanInfoClass, clasz.symbol) - } - - } // end of class JBeanInfoBuilder - - /** A namespace for utilities to normalize the code of an IMethod, over and beyond what IMethod.normalize() strives for. - * In particular, IMethod.normalize() doesn't collapseJumpChains(). - * - * TODO Eventually, these utilities should be moved to IMethod and reused from normalize() (there's nothing JVM-specific about them). - */ - object newNormal { - /** - * True if a block is "jump only" which is defined - * as being a block that consists only of 0 or more instructions that - * won't make it to the JVM followed by a JUMP. - */ - def isJumpOnly(b: BasicBlock): Boolean = { - val nonICode = firstNonIcodeOnlyInstructions(b) - // by definition a block has to have a jump, conditional jump, return, or throw - assert(nonICode.hasNext, "empty block") - nonICode.next.isInstanceOf[JUMP] - } - - /** - * Returns the list of instructions in a block that follow all ICode only instructions, - * where an ICode only instruction is one that won't make it to the JVM - */ - private def firstNonIcodeOnlyInstructions(b: BasicBlock): Iterator[Instruction] = { - def isICodeOnlyInstruction(i: Instruction) = i match { - case LOAD_EXCEPTION(_) | SCOPE_ENTER(_) | SCOPE_EXIT(_) => true - case _ => false - } - b.iterator dropWhile isICodeOnlyInstruction - } - - /** - * Returns the target of a block that is "jump only" which is defined - * as being a block that consists only of 0 or more instructions that - * won't make it to the JVM followed by a JUMP. - * - * @param b The basic block to examine - * @return Some(target) if b is a "jump only" block or None if it's not - */ - private def getJumpOnlyTarget(b: BasicBlock): Option[BasicBlock] = { - val nonICode = firstNonIcodeOnlyInstructions(b) - // by definition a block has to have a jump, conditional jump, return, or throw - assert(nonICode.nonEmpty, "empty block") - nonICode.next match { - case JUMP(whereto) => - assert(!nonICode.hasNext, "A block contains instructions after JUMP (looks like enterIgnoreMode() was itself ignored.)") - Some(whereto) - case _ => None - } - } - - /** - * Collapse a chain of "jump-only" blocks such as: - * - * JUMP b1; - * b1: JUMP b2; - * b2: JUMP ... etc. - * - * by re-wiring predecessors to target directly the "final destination". - * Even if covered by an exception handler, a "non-self-loop jump-only block" can always be removed. - - * Returns true if any replacement was made, false otherwise. - * - * In more detail: - * Starting at each of the entry points (m.startBlock, the start block of each exception handler) - * rephrase those control-flow instructions targeting a jump-only block (which jumps to a final destination D) to target D. - * The blocks thus skipped become eligible to removed by the reachability analyzer - * - * Rationale for this normalization: - * test/files/run/private-inline.scala after -optimize is chock full of - * BasicBlocks containing just JUMP(whereto), where no exception handler straddles them. - * They should be collapsed by IMethod.normalize() but aren't. - * That was fine in FJBG times when by the time the exception table was emitted, - * it already contained "anchored" labels (ie instruction offsets were known) - * and thus ranges with identical (start, end) (i.e, identical after GenJVM omitted the JUMPs in question) - * could be weeded out to avoid "java.lang.ClassFormatError: Illegal exception table range" - * Now that visitTryCatchBlock() must be called before Labels are resolved, - * renders the BasicBlocks described above (to recap, consisting of just a JUMP) unreachable. - */ - private def collapseJumpOnlyBlocks(m: IMethod) { - assert(m.hasCode, "code-less method") - - def rephraseGotos(detour: mutable.Map[BasicBlock, BasicBlock]) { - def lookup(b: BasicBlock) = detour.getOrElse(b, b) - - m.code.startBlock = lookup(m.code.startBlock) - - for(eh <- m.exh) - eh.setStartBlock(lookup(eh.startBlock)) - - for (b <- m.blocks) { - def replaceLastInstruction(i: Instruction) = { - if (b.lastInstruction != i) { - val idxLast = b.size - 1 - debuglog(s"In block $b, replacing last instruction ${b.lastInstruction} with ${i}") - b.replaceInstruction(idxLast, i) - } - } - - b.lastInstruction match { - case JUMP(whereto) => - replaceLastInstruction(JUMP(lookup(whereto))) - case CJUMP(succ, fail, cond, kind) => - replaceLastInstruction(CJUMP(lookup(succ), lookup(fail), cond, kind)) - case CZJUMP(succ, fail, cond, kind) => - replaceLastInstruction(CZJUMP(lookup(succ), lookup(fail), cond, kind)) - case SWITCH(tags, labels) => - val newLabels = (labels map lookup) - replaceLastInstruction(SWITCH(tags, newLabels)) - case _ => () - } - } - } - - /* - * Computes a mapping from jump only block to its - * final destination which is either a non-jump-only - * block or, if it's in a jump-only block cycle, is - * itself - */ - def computeDetour: mutable.Map[BasicBlock, BasicBlock] = { - // fetch the jump only blocks and their immediate destinations - val pairs = for { - block <- m.blocks.toIterator - target <- getJumpOnlyTarget(block) - } yield(block, target) - - // mapping from a jump-only block to our current knowledge of its - // final destination. Initially it's just jump block to immediate jump - // target - val detour = mutable.Map[BasicBlock, BasicBlock](pairs.toSeq:_*) - - // for each jump-only block find its final destination - // taking advantage of the destinations we found for previous - // blocks - for (key <- detour.keySet) { - // we use the Robert Floyd's classic Tortoise and Hare algorithm - @tailrec - def findDestination(tortoise: BasicBlock, hare: BasicBlock): BasicBlock = { - if (tortoise == hare) - // cycle detected, map key to key - key - else if (detour contains hare) { - // advance hare once - val hare1 = detour(hare) - // make sure we can advance hare a second time - if (detour contains hare1) - // advance tortoise once and hare a second time - findDestination(detour(tortoise), detour(hare1)) - else - // hare1 is not in the map so it's not a jump-only block, it's the destination - hare1 - } else - // hare is not in the map so it's not a jump-only block, it's the destination - hare - } - // update the mapping for key based on its final destination - detour(key) = findDestination(key, detour(key)) - } - detour - } - - val detour = computeDetour - rephraseGotos(detour) - - if (settings.debug) { - val (remappings, cycles) = detour partition {case (source, target) => source != target} - for ((source, target) <- remappings) { - debuglog(s"Will elide jump only block $source because it can be jumped around to get to $target.") - if (m.startBlock == source) devWarning("startBlock should have been re-wired by now") - } - val sources = remappings.keySet - val targets = remappings.values.toSet - val intersection = sources intersect targets - - if (intersection.nonEmpty) devWarning(s"contradiction: we seem to have some source and target overlap in blocks ${intersection.mkString}. Map was ${detour.mkString}") - - for ((source, _) <- cycles) { - debuglog(s"Block $source is in a do-nothing infinite loop. Did the user write 'while(true){}'?") - } - } - } - - /** - * Removes all blocks that are unreachable in a method using a standard reachability analysis. - */ - def elimUnreachableBlocks(m: IMethod) { - assert(m.hasCode, "code-less method") - - // assume nothing is reachable until we prove it can be reached - val reachable = mutable.Set[BasicBlock]() - - // the set of blocks that we know are reachable but have - // yet to be marked reachable, initially only the start block - val worklist = mutable.Set(m.startBlock) - - while (worklist.nonEmpty) { - val block = worklist.head - worklist remove block - // we know that one is reachable - reachable add block - // so are its successors, so go back around and add the ones we still - // think are unreachable - worklist ++= (block.successors filterNot reachable) - } - - // exception handlers need to be told not to cover unreachable blocks - // and exception handlers that no longer cover any blocks need to be - // removed entirely - val unusedExceptionHandlers = mutable.Set[ExceptionHandler]() - for (exh <- m.exh) { - exh.covered = exh.covered filter reachable - if (exh.covered.isEmpty) { - unusedExceptionHandlers += exh - } - } - - // remove the unused exception handler references - if (settings.debug) - for (exh <- unusedExceptionHandlers) debuglog(s"eliding exception handler $exh because it does not cover any reachable blocks") - m.exh = m.exh filterNot unusedExceptionHandlers - - // everything not in the reachable set is unreachable, unused, and unloved. buh bye - for (b <- m.blocks filterNot reachable) { - debuglog(s"eliding block $b because it is unreachable") - m.code removeBlock b - } - } - - def normalize(m: IMethod) { - if(!m.hasCode) { return } - collapseJumpOnlyBlocks(m) - if (settings.optimise) - elimUnreachableBlocks(m) - icodes checkValid m - } - - } - - // @M don't generate java generics sigs for (members of) implementation - // classes, as they are monomorphic (TODO: ok?) - private def needsGenericSignature(sym: Symbol) = !( - // PP: This condition used to include sym.hasExpandedName, but this leads - // to the total loss of generic information if a private member is - // accessed from a closure: both the field and the accessor were generated - // without it. This is particularly bad because the availability of - // generic information could disappear as a consequence of a seemingly - // unrelated change. - settings.Ynogenericsig - || sym.isArtifact - || sym.isLiftedMethod - || sym.isBridge - || (sym.ownerChain exists (_.isImplClass)) - ) - - final def staticForwarderGenericSignature(sym: Symbol, moduleClass: Symbol, unit: CompilationUnit): String = { - if (sym.isDeferred) null // only add generic signature if method concrete; bug #1745 - else { - // SI-3452 Static forwarder generation uses the same erased signature as the method if forwards to. - // By rights, it should use the signature as-seen-from the module class, and add suitable - // primitive and value-class boxing/unboxing. - // But for now, just like we did in mixin, we just avoid writing a wrong generic signature - // (one that doesn't erase to the actual signature). See run/t3452b for a test case. - val memberTpe = enteringErasure(moduleClass.thisType.memberInfo(sym)) - val erasedMemberType = erasure.erasure(sym)(memberTpe) - if (erasedMemberType =:= sym.info) - getGenericSignature(sym, moduleClass, memberTpe, unit) - else null - } - } - - /** @return - * - `null` if no Java signature is to be added (`null` is what ASM expects in these cases). - * - otherwise the signature in question - */ - def getGenericSignature(sym: Symbol, owner: Symbol, unit: CompilationUnit): String = { - val memberTpe = enteringErasure(owner.thisType.memberInfo(sym)) - getGenericSignature(sym, owner, memberTpe, unit) - } - def getGenericSignature(sym: Symbol, owner: Symbol, memberTpe: Type, unit: CompilationUnit): String = { - if (!needsGenericSignature(sym)) { return null } - - val jsOpt: Option[String] = erasure.javaSig(sym, memberTpe) - if (jsOpt.isEmpty) { return null } - - val sig = jsOpt.get - log(sig) // This seems useful enough in the general case. - - def wrap(op: => Unit) = { - try { op; true } - catch { case _: Throwable => false } - } - - if (settings.Xverify) { - // Run the signature parser to catch bogus signatures. - val isValidSignature = wrap { - // Alternative: scala.tools.reflect.SigParser (frontend to sun.reflect.generics.parser.SignatureParser) - import scala.tools.asm.util.CheckClassAdapter - if (sym.isMethod) { CheckClassAdapter checkMethodSignature sig } // requires asm-util.jar - else if (sym.isTerm) { CheckClassAdapter checkFieldSignature sig } - else { CheckClassAdapter checkClassSignature sig } - } - - if(!isValidSignature) { - reporter.warning(sym.pos, - """|compiler bug: created invalid generic signature for %s in %s - |signature: %s - |if this is reproducible, please report bug at https://issues.scala-lang.org/ - """.trim.stripMargin.format(sym, sym.owner.skipPackageObject.fullName, sig)) - return null - } - } - - if ((settings.check containsName phaseName)) { - val normalizedTpe = enteringErasure(erasure.prepareSigMap(memberTpe)) - val bytecodeTpe = owner.thisType.memberInfo(sym) - if (!sym.isType && !sym.isConstructor && !(erasure.erasure(sym)(normalizedTpe) =:= bytecodeTpe)) { - reporter.warning(sym.pos, - """|compiler bug: created generic signature for %s in %s that does not conform to its erasure - |signature: %s - |original type: %s - |normalized type: %s - |erasure type: %s - |if this is reproducible, please report bug at http://issues.scala-lang.org/ - """.trim.stripMargin.format(sym, sym.owner.skipPackageObject.fullName, sig, memberTpe, normalizedTpe, bytecodeTpe)) - return null - } - } - - sig - } - - def ubytesToCharArray(bytes: Array[Byte]): Array[Char] = { - val ca = new Array[Char](bytes.length) - var idx = 0 - while(idx < bytes.length) { - val b: Byte = bytes(idx) - assert((b & ~0x7f) == 0) - ca(idx) = b.asInstanceOf[Char] - idx += 1 - } - - ca - } - - final def arrEncode(sb: ScalaSigBytes): Array[String] = { - var strs: List[String] = Nil - val bSeven: Array[Byte] = sb.sevenBitsMayBeZero - // chop into slices of at most 65535 bytes, counting 0x00 as taking two bytes (as per JVMS 4.4.7 The CONSTANT_Utf8_info Structure) - var prevOffset = 0 - var offset = 0 - var encLength = 0 - while(offset < bSeven.length) { - val deltaEncLength = (if(bSeven(offset) == 0) 2 else 1) - val newEncLength = encLength.toLong + deltaEncLength - if(newEncLength >= 65535) { - val ba = bSeven.slice(prevOffset, offset) - strs ::= new java.lang.String(ubytesToCharArray(ba)) - encLength = 0 - prevOffset = offset - } else { - encLength += deltaEncLength - offset += 1 - } - } - if(prevOffset < offset) { - assert(offset == bSeven.length) - val ba = bSeven.slice(prevOffset, offset) - strs ::= new java.lang.String(ubytesToCharArray(ba)) - } - assert(strs.size > 1, "encode instead as one String via strEncode()") // TODO too strict? - strs.reverse.toArray - } - - private def strEncode(sb: ScalaSigBytes): String = { - val ca = ubytesToCharArray(sb.sevenBitsMayBeZero) - new java.lang.String(ca) - // debug val bvA = new asm.ByteVector; bvA.putUTF8(s) - // debug val enc: Array[Byte] = scala.reflect.internal.pickling.ByteCodecs.encode(bytes) - // debug assert(enc(idx) == bvA.getByte(idx + 2)) - // debug assert(bvA.getLength == enc.size + 2) - } -} diff --git a/src/compiler/scala/tools/nsc/backend/jvm/GenBCode.scala b/src/compiler/scala/tools/nsc/backend/jvm/GenBCode.scala index af962c4ce0..6593d4b725 100644 --- a/src/compiler/scala/tools/nsc/backend/jvm/GenBCode.scala +++ b/src/compiler/scala/tools/nsc/backend/jvm/GenBCode.scala @@ -14,6 +14,7 @@ import scala.reflect.internal.util.Statistics import scala.tools.asm import scala.tools.asm.tree.ClassNode +import scala.tools.nsc.backend.jvm.opt.ByteCodeRepository /* * Prepare in-memory representations of classfiles using the ASM Tree API, and serialize them to disk. @@ -76,15 +77,16 @@ abstract class GenBCode extends BCodeSyncAndTry { /* ---------------- q2 ---------------- */ - case class Item2(arrivalPos: Int, - mirror: asm.tree.ClassNode, - plain: asm.tree.ClassNode, - bean: asm.tree.ClassNode, - outFolder: scala.tools.nsc.io.AbstractFile) { + case class Item2(arrivalPos: Int, + mirror: asm.tree.ClassNode, + plain: asm.tree.ClassNode, + bean: asm.tree.ClassNode, + sourceFilePath: String, + outFolder: scala.tools.nsc.io.AbstractFile) { def isPoison = { arrivalPos == Int.MaxValue } } - private val poison2 = Item2(Int.MaxValue, null, null, null, null) + private val poison2 = Item2(Int.MaxValue, null, null, null, null, null) private val q2 = new _root_.java.util.LinkedList[Item2] /* ---------------- q3 ---------------- */ @@ -134,7 +136,7 @@ abstract class GenBCode extends BCodeSyncAndTry { return } else { - try { withCurrentUnit(item.cunit)(visit(item)) } + try { withCurrentUnitNoLog(item.cunit)(visit(item)) } catch { case ex: Throwable => ex.printStackTrace() @@ -186,7 +188,7 @@ abstract class GenBCode extends BCodeSyncAndTry { // -------------- "plain" class -------------- val pcb = new PlainClassBuilder(cunit) pcb.genPlainClass(cd) - val outF = if (needsOutFolder) getOutFolder(claszSymbol, pcb.thisName, cunit) else null; + val outF = if (needsOutFolder) getOutFolder(claszSymbol, pcb.thisBType.internalName, cunit) else null val plainC = pcb.cnode // -------------- bean info class, if needed -------------- @@ -204,6 +206,7 @@ abstract class GenBCode extends BCodeSyncAndTry { val item2 = Item2(arrivalPos, mirrorC, plainC, beanC, + cunit.source.file.canonicalPath, outF) q2 add item2 // at the very end of this method so that no Worker2 thread starts mutating before we're done. @@ -220,17 +223,24 @@ abstract class GenBCode extends BCodeSyncAndTry { */ class Worker2 { def runGlobalOptimizations(): Unit = { - import scala.collection.convert.decorateAsScala._ - if (settings.YoptBuildCallGraph) { - q2.asScala foreach { - case Item2(_, _, plain, _, _) => - // skip mirror / bean: wd don't inline into tem, and they are not used in the plain class - if (plain != null) callGraph.addClass(plain) - } + import scala.collection.JavaConverters._ + + // add classes to the bytecode repo before building the call graph: the latter needs to + // look up classes and methods in the code repo. + if (settings.optAddToBytecodeRepository) q2.asScala foreach { + case Item2(_, mirror, plain, bean, sourceFilePath, _) => + val someSourceFilePath = Some(sourceFilePath) + if (mirror != null) byteCodeRepository.add(mirror, someSourceFilePath) + if (plain != null) byteCodeRepository.add(plain, someSourceFilePath) + if (bean != null) byteCodeRepository.add(bean, someSourceFilePath) + } + if (settings.optBuildCallGraph) q2.asScala foreach { item => + // skip call graph for mirror / bean: wd don't inline into tem, and they are not used in the plain class + if (item.plain != null) callGraph.addClass(item.plain) } - if (settings.YoptInlinerEnabled) + if (settings.optInlinerEnabled) bTypes.inliner.runInliner() - if (settings.YoptClosureElimination) + if (settings.optClosureInvocations) closureOptimizer.rewriteClosureApplyInvocations() } @@ -238,6 +248,11 @@ abstract class GenBCode extends BCodeSyncAndTry { BackendStats.timed(BackendStats.methodOptTimer)(localOpt.methodOptimizations(classNode)) } + def setInnerClasses(classNode: ClassNode): Unit = if (classNode != null) { + classNode.innerClasses.clear() + addInnerClasses(classNode, bTypes.backendUtils.collectNestedClasses(classNode)) + } + def run() { runGlobalOptimizations() @@ -250,8 +265,17 @@ abstract class GenBCode extends BCodeSyncAndTry { else { try { localOptimizations(item.plain) + setInnerClasses(item.plain) + val lambdaImplMethods = getIndyLambdaImplMethods(item.plain.name) + if (lambdaImplMethods.nonEmpty) + backendUtils.addLambdaDeserialize(item.plain, lambdaImplMethods) + setInnerClasses(item.mirror) + setInnerClasses(item.bean) addToQ3(item) } catch { + case e: java.lang.RuntimeException if e.getMessage != null && (e.getMessage contains "too large!") => + reporter.error(NoPosition, + s"Could not write class ${item.plain.name} because it exceeds JVM code size limits. ${e.getMessage}") case ex: Throwable => ex.printStackTrace() error(s"Error while emitting ${item.plain.name}\n${ex.getMessage}") @@ -268,7 +292,7 @@ abstract class GenBCode extends BCodeSyncAndTry { cw.toByteArray } - val Item2(arrivalPos, mirror, plain, bean, outFolder) = item + val Item2(arrivalPos, mirror, plain, bean, _, outFolder) = item val mirrorC = if (mirror == null) null else SubItem3(mirror.name, getByteArray(mirror)) val plainC = SubItem3(plain.name, getByteArray(plain)) @@ -313,7 +337,7 @@ abstract class GenBCode extends BCodeSyncAndTry { bTypes.initializeCoreBTypes() bTypes.javaDefinedClasses.clear() bTypes.javaDefinedClasses ++= currentRun.symSource collect { - case (sym, _) if sym.isJavaDefined => sym.javaBinaryName.toString + case (sym, _) if sym.isJavaDefined => sym.javaBinaryNameString } Statistics.stopTimer(BackendStats.bcodeInitTimer, initStart) diff --git a/src/compiler/scala/tools/nsc/backend/jvm/analysis/AliasingFrame.scala b/src/compiler/scala/tools/nsc/backend/jvm/analysis/AliasingFrame.scala index 7bbe1e2a49..086946e4e3 100644 --- a/src/compiler/scala/tools/nsc/backend/jvm/analysis/AliasingFrame.scala +++ b/src/compiler/scala/tools/nsc/backend/jvm/analysis/AliasingFrame.scala @@ -3,17 +3,22 @@ package backend.jvm package analysis import scala.annotation.switch -import scala.collection.{mutable, immutable} +import scala.collection.mutable import scala.tools.asm.Opcodes import scala.tools.asm.tree._ import scala.tools.asm.tree.analysis.{Analyzer, Value, Frame, Interpreter} import opt.BytecodeUtils._ +import AliasSet.SmallBitSet -object AliasingFrame { - private var _idCounter: Long = 0l - private def nextId = { _idCounter += 1; _idCounter } -} - +/** + * A subclass of Frame that tracks aliasing of values stored in local variables and on the stack. + * + * Note: an analysis tracking aliases is roughly 5x slower than a usual analysis (assuming a simple + * value domain with a fast merge function). For example, nullness analysis is roughly 5x slower + * than a BasicValue analysis. + * + * See the doc of package object `analysis` for some notes on the performance of alias analysis. + */ class AliasingFrame[V <: Value](nLocals: Int, nStack: Int) extends Frame[V](nLocals, nStack) { import Opcodes._ @@ -23,63 +28,80 @@ class AliasingFrame[V <: Value](nLocals: Int, nStack: Int) extends Frame[V](nLoc init(src) } - /** - * For each slot (entry in the `values` array of the frame), an id that uniquely represents - * the object stored in it. If two values have the same id, they are aliases of the same - * object. - */ - private val aliasIds: Array[Long] = Array.fill(nLocals + nStack)(AliasingFrame.nextId) + override def toString: String = super.toString + " - " + aliases.toList.filter(s => s != null && s.size > 1).map(_.toString).distinct.mkString(",") /** - * The object alias id of for a value index. - */ - def aliasId(entry: Int) = aliasIds(entry) - - /** - * Returns the indices of the values array which are aliases of the object `id`. + * For every value the set of values that are aliases of it. + * + * Invariants: + * - If `aliases(i) == null` then i has no aliases. This is equivalent to having + * `aliases(i) == SingletonSet(i)`. + * - If `aliases(i) != null` then `aliases(i) contains i`. + * - If `aliases(i) contains j` then `aliases(i) eq aliases(j)`, i.e., they are references to the + * same (mutable) AliasSet. */ - def valuesWithAliasId(id: Long): Set[Int] = immutable.BitSet.empty ++ aliasIds.indices.iterator.filter(i => aliasId(i) == id) + val aliases: Array[AliasSet] = new Array[AliasSet](getLocals + getMaxStackSize) /** * The set of aliased values for a given entry in the `values` array. */ - def aliasesOf(entry: Int): Set[Int] = valuesWithAliasId(aliasIds(entry)) + def aliasesOf(entry: Int): AliasSet = { + if (aliases(entry) != null) aliases(entry) + else { + val init = new AliasSet(new AliasSet.SmallBitSet(entry, -1, -1, -1), 1) + aliases(entry) = init + init + } + } /** - * Define a new alias. For example, given - * var a = this // this, a have the same aliasId - * then an assignment + * Define a new alias. For example, an assignment * b = a - * will set the same the aliasId for `b`. + * adds b to the set of aliases of a. */ private def newAlias(assignee: Int, source: Int): Unit = { - aliasIds(assignee) = aliasIds(source) + removeAlias(assignee) + val sourceAliases = aliasesOf(source) + sourceAliases += assignee + aliases(assignee) = sourceAliases } /** - * An assignment + * Remove an alias. For example, an assignment * a = someUnknownValue() - * sets a fresh alias id for `a`. - * A stack value is also removed from its alias set when being consumed. + * removes a from its former alias set. + * As another example, stack values are removed from their alias sets when being consumed. */ private def removeAlias(assignee: Int): Unit = { - aliasIds(assignee) = AliasingFrame.nextId + if (aliases(assignee) != null) { + aliases(assignee) -= assignee + aliases(assignee) = null + } + } + + /** + * Define the alias set for a given value. + */ + private def setAliasSet(assignee: Int, set: AliasSet): Unit = { + if (aliases(assignee) != null) { + aliases(assignee) -= assignee + } + aliases(assignee) = set } override def execute(insn: AbstractInsnNode, interpreter: Interpreter[V]): Unit = { - // Make the extendsion methods easier to use (otherwise we have to repeat `this`.stackTop) + // Make the extension methods easier to use (otherwise we have to repeat `this`.stackTop) def stackTop: Int = this.stackTop def peekStack(n: Int): V = this.peekStack(n) - // the val pattern `val (p, c) = f` still allocates a tuple (https://github.com/scala-opt/scala/issues/28) - val prodCons = InstructionStackEffect(insn, this) // needs to be called before super.execute, see its doc - val consumed = prodCons._1 - val produced = prodCons._2 + val prodCons = InstructionStackEffect.forAsmAnalysis(insn, this) // needs to be called before super.execute, see its doc + val consumed = InstructionStackEffect.cons(prodCons) + val produced = InstructionStackEffect.prod(prodCons) super.execute(insn, interpreter) (insn.getOpcode: @switch) match { - case ALOAD => + case ILOAD | LLOAD | FLOAD | DLOAD | ALOAD => newAlias(assignee = stackTop, source = insn.asInstanceOf[VarInsnNode].`var`) case DUP => @@ -166,31 +188,54 @@ class AliasingFrame[V <: Value](nLocals: Int, nStack: Int) extends Frame[V](nLoc } case SWAP => + // could be written more elegantly with higher-order combinators, but thinking of performance val top = stackTop - val idTop = aliasIds(top) - aliasIds(top) = aliasIds(top - 1) - aliasIds(top - 1) = idTop - case opcode => - if (opcode == ASTORE) { - // Not a separate case because we need to remove the consumed stack value from alias sets after. - val stackTopBefore = stackTop - produced + consumed - val local = insn.asInstanceOf[VarInsnNode].`var` - newAlias(assignee = local, source = stackTopBefore) - // if the value written is size 2, it overwrites the subsequent slot, which is then no - // longer an alias of anything. see the corresponding case in `Frame.execute`. - if (getLocal(local).getSize == 2) - removeAlias(local + 1) - - // if the value at the preceding index is size 2, it is no longer valid, so we remove its - // aliasing. see corresponding case in `Frame.execute` - if (local > 0) { - val precedingValue = getLocal(local - 1) - if (precedingValue != null && precedingValue.getSize == 2) - removeAlias(local - 1) + def moveNextToTop(): Unit = { + val nextAliases = aliases(top - 1) + aliases(top) = nextAliases + nextAliases -= (top - 1) + nextAliases += top + } + + if (aliases(top) != null) { + val topAliases = aliases(top) + if (aliases(top - 1) != null) moveNextToTop() + else aliases(top) = null + // move top to next + aliases(top - 1) = topAliases + topAliases -= top + topAliases += (top - 1) + } else { + if (aliases(top - 1) != null) { + moveNextToTop() + aliases(top - 1) = null } } + case opcode => + (opcode: @switch) match { + case ISTORE | LSTORE | FSTORE | DSTORE | ASTORE => + // not a separate case: we re-use the code below that removes the consumed stack value from alias sets + val stackTopBefore = stackTop - produced + consumed + val local = insn.asInstanceOf[VarInsnNode].`var` + newAlias(assignee = local, source = stackTopBefore) + // if the value written is size 2, it overwrites the subsequent slot, which is then no + // longer an alias of anything. see the corresponding case in `Frame.execute`. + if (getLocal(local).getSize == 2) + removeAlias(local + 1) + + // if the value at the preceding index is size 2, it is no longer valid, so we remove its + // aliasing. see corresponding case in `Frame.execute` + if (local > 0) { + val precedingValue = getLocal(local - 1) + if (precedingValue != null && precedingValue.getSize == 2) + removeAlias(local - 1) + } + + case _ => + } + // Remove consumed stack values from aliasing sets. // Example: iadd // - before: local1, local2, stack1, consumed1, consumed2 @@ -198,10 +243,22 @@ class AliasingFrame[V <: Value](nLocals: Int, nStack: Int) extends Frame[V](nLoc val firstConsumed = stackTop - produced + 1 // firstConsumed = 3 for (i <- 0 until consumed) removeAlias(firstConsumed + i) // remove aliases for 3 and 4 + } + } - // We don't need to set the aliases ids for the produced values: the aliasIds array already - // contains fresh ids for non-used stack values (ensured by removeAlias). + /** + * When entering an exception handler, all values are dropped from the stack (and the exception + * value is pushed). The ASM analyzer invokes `firstHandlerInstructionFrame.clearStack()`. To + * ensure consistent aliasing sets, we need to remove the dropped values from aliasing sets. + */ + override def clearStack(): Unit = { + var i = getLocals + val end = i + getStackSize + while (i < end) { + removeAlias(i) + i += 1 } + super.clearStack() } /** @@ -217,30 +274,131 @@ class AliasingFrame[V <: Value](nLocals: Int, nStack: Int) extends Frame[V](nLoc * x = a * y = b // (x, a) and (y, b) * } - * [...] // (x, a) + * [...] // (x, a) -- merge of ((x, y, a)) and ((x, a), (y, b)) */ override def merge(other: Frame[_ <: V], interpreter: Interpreter[V]): Boolean = { + // merge is the main performance hot spot of a data flow analysis. + + // in nullness analysis, super.merge (which actually merges the nullness values) takes 20% of + // the overall analysis time. val valuesChanged = super.merge(other, interpreter) + + // in nullness analysis, merging the alias sets takes ~55% of the analysis time. therefore, this + // code has been heavily optimized. most of the time is spent in the `hasNext` method of the + // andNotIterator, see its comment. + var aliasesChanged = false val aliasingOther = other.asInstanceOf[AliasingFrame[_]] - for (i <- aliasIds.indices) { - val thisAliases = aliasesOf(i) - val thisNotOther = thisAliases diff (thisAliases intersect aliasingOther.aliasesOf(i)) - if (thisNotOther.nonEmpty) { - aliasesChanged = true - thisNotOther foreach removeAlias + + val numValues = getLocals + getStackSize + // assume (a, b) are aliases both in this frame, and the other frame. when merging the alias set + // for a, we already see that a and b will be aliases in the final result. so we can skip over + // merging the alias set for b. in this case, while merging the sets for a, knownOk(b) will be + // set to `true`. + val knownOk = new Array[Boolean](numValues) + var i = 0 + while (i < numValues) { + if (!knownOk(i)) { + val thisAliases = this.aliases(i) + val otherAliases = aliasingOther.aliases(i) + if (thisAliases != null) { + if (otherAliases == null) { + if (thisAliases.size > 1) { + aliasesChanged = true + removeAlias(i) + } + } else { + // The iterator yields elements that are in `thisAliases` but not in `otherAliases`. + // As a side-effect, for every index `i` that is in both alias sets, the iterator sets + // `knownOk(i) = true`: the alias sets for these values don't need to be merged again. + val thisNotOtherIt = AliasSet.andNotIterator(thisAliases, otherAliases, knownOk) + if (thisNotOtherIt.hasNext) { + aliasesChanged = true + val newSet = AliasSet.empty + while (thisNotOtherIt.hasNext) { + val next = thisNotOtherIt.next() + newSet += next + setAliasSet(next, newSet) + } + } + } + } } + i += 1 } + valuesChanged || aliasesChanged } + private def min(s: SmallBitSet) = { + var r = s.a + if ( s.b < r) r = s.b + if (s.c != -1 && s.c < r) r = s.c + if (s.d != -1 && s.d < r) r = s.d + r + } + override def init(src: Frame[_ <: V]): Frame[V] = { - super.init(src) - compat.Platform.arraycopy(src.asInstanceOf[AliasingFrame[_]].aliasIds, 0, aliasIds, 0, aliasIds.length) + super.init(src) // very quick (just an arraycopy) + System.arraycopy(src.asInstanceOf[AliasingFrame[_]].aliases, 0, aliases, 0, aliases.length) // also quick + + val newSets = mutable.HashMap.empty[AliasSet, AliasSet] + + // the rest of this method (cloning alias sets) is the second performance˙hotspot (next to + // AliasingFrame.merge). for nullness, it takes ~20% of the analysis time. + // the difficulty here is that we have to clone the alias sets correctly. if two values a, b are + // aliases, then aliases(a) eq aliases(b). we need to make sure to use the same clone for the + // two values. + + var i = 0 + while (i < aliases.length) { + val set = aliases(i) + if (set != null) { + // size cannot be 0 - alias sets are always at least singletons. + // for sets of size 1-4, don't use the `newSets` map - lookup / update is slow + if (set.size == 1) { + aliases(i) = null + } else if (set.size <= 4) { + val small = set.set.asInstanceOf[AliasSet.SmallBitSet] + val firstOfSet = i == min(small) + if (firstOfSet) { + val newSet = set.clone() + aliases(small.a) = newSet + aliases(small.b) = newSet + if (small.c != -1) aliases(small.c) = newSet + if (small.d != -1) aliases(small.d) = newSet + } + } else { + // the actual hot spot is the hash map operations here: this is where almost all of the 20% + // mentioned above is spent. + // i also benchmarked an alternative implementation: keep an array of booleans for indexes + // that already contain the cloned set. iterate through all elements of the cloned set and + // assign the cloned set. this approach is 50% slower than using a hash map. + if (newSets contains set) aliases(i) = newSets(set) + else { + val newSet = set.clone() + newSets(set) = newSet + aliases(i) = newSet + } + } + } + i += 1 + } this } } +object AliasingFrame { +// val start1 = AliasingFrame.timer1.start() +// AliasingFrame.timer1.stop(start1) + import scala.reflect.internal.util.Statistics._ + val timer1 = newTimer("t1", "jvm") + val timer2 = newTimer("t2", "jvm") + val timer3 = newTimer("t3", "jvm") + val timers = List(timer1, timer2, timer3) + def reset(): Unit = for (t <- timers) { t.nanos = 0; t.timings = 0 } +} + /** * An analyzer that uses AliasingFrames instead of bare Frames. This can be used when an analysis * needs to track aliases, but doesn't require a more specific Frame subclass. @@ -249,3 +407,269 @@ class AliasingAnalyzer[V <: Value](interpreter: Interpreter[V]) extends Analyzer override def newFrame(nLocals: Int, nStack: Int): AliasingFrame[V] = new AliasingFrame(nLocals, nStack) override def newFrame(src: Frame[_ <: V]): AliasingFrame[V] = new AliasingFrame(src) } + +/** + * An iterator over Int (required to prevent boxing the result of next). + */ +abstract class IntIterator extends Iterator[Int] { + def hasNext: Boolean + def next(): Int +} + +/** + * An efficient mutable bit set. + * + * @param set Either a SmallBitSet or an Array[Long] + * @param size The size of the set, useful for performance of certain operations + */ +class AliasSet(var set: Object /*SmallBitSet | Array[Long]*/, var size: Int) { + import AliasSet._ + + override def toString: String = iterator.toSet.mkString("<", ",", ">") + + /** + * An iterator for the elements of this bit set. Note that only one iterator can be used at a + * time. Also make sure not to change the underlying AliasSet during iteration. + */ + def iterator: IntIterator = andNotIterator(this, empty, null) + + def +=(value: Int): Unit = this.set match { + case s: SmallBitSet => (size: @switch) match { + case 0 => s.a = value; size = 1 + case 1 => if (value != s.a) { s.b = value; size = 2 } + case 2 => if (value != s.a && value != s.b) { s.c = value; size = 3 } + case 3 => if (value != s.a && value != s.b && value != s.c) { s.d = value; size = 4 } + case 4 => + if (value != s.a && value != s.b && value != s.c && value != s.d) { + this.set = bsEmpty + this.size = 0 + bsAdd(this, s.a) + bsAdd(this, s.b) + bsAdd(this, s.c) + bsAdd(this, s.d) + bsAdd(this, value) + } + } + case bits: Array[Long] => + bsAdd(this, value) + } + + def -=(value: Int): Unit = this.set match { + case s: SmallBitSet => (size: @switch) match { + case 0 => + case 1 => + if (value == s.a) { s.a = -1; size = 0 } + case 2 => + if (value == s.a) { s.a = s.b; s.b = -1; size = 1 } + else if (value == s.b) { s.b = -1; size = 1 } + case 3 => + if (value == s.a) { s.a = s.b; s.b = s.c; s.c = -1; size = 2 } + else if (value == s.b) { s.b = s.c; s.c = -1; size = 2 } + else if (value == s.c) { s.c = -1; size = 2 } + case 4 => + if (value == s.a) { s.a = s.b; s.b = s.c; s.c = s.d; s.d = -1; size = 3 } + else if (value == s.b) { s.b = s.c; s.c = s.d; s.d = -1; size = 3 } + else if (value == s.c) { s.c = s.d; s.d = -1; size = 3 } + else if (value == s.d) { s.d = -1; size = 3 } + } + case bits: Array[Long] => + bsRemove(this, value) + if (this.size == 4) + this.set = bsToSmall(this.set.asInstanceOf[Array[Long]]) + } + + override def clone(): AliasSet = { + val resSet = this.set match { + case s: SmallBitSet => new SmallBitSet(s.a, s.b, s.c, s.d) + case bits: Array[Long] => bits.clone() + } + new AliasSet(resSet, this.size) + } +} + +object AliasSet { + def empty = new AliasSet(new SmallBitSet(-1, -1, -1, -1), 0) + + final class SmallBitSet(var a: Int, var b: Int, var c: Int, var d: Int) { + override def toString = s"($a, $b, $c, $d)" + } + + def bsEmpty: Array[Long] = new Array[Long](1) + + private def bsEnsureCapacity(set: Array[Long], index: Int): Array[Long] = { + if (index < set.length) set + else { + var newLength = set.length + while (index >= newLength) newLength *= 2 + val newSet = new Array[Long](newLength) + Array.copy(set, 0, newSet, 0, set.length) + newSet + } + } + + def bsAdd(set: AliasSet, bit: Int): Unit = { + val bits = set.set.asInstanceOf[Array[Long]] + val index = bit >> 6 + val resSet = bsEnsureCapacity(bits, index) + val before = resSet(index) + val result = before | (1l << bit) + if (result != before) { + resSet(index) = result + set.set = resSet + set.size += 1 + } + } + + def bsRemove(set: AliasSet, bit: Int): Unit = { + val bits = set.set.asInstanceOf[Array[Long]] + val index = bit >> 6 + if (index < bits.length) { + val before = bits(index) + val result = before & ~(1l << bit) + if (result != before) { + bits(index) = result + set.size -= 1 + } + } + } + + def bsContains(set: Array[Long], bit: Int): Boolean = { + val index = bit >> 6 + bit >= 0 && index < set.length && (set(index) & (1L << bit)) != 0L + } + +// var sizesHist: Array[Int] = new Array[Int](1000) + + /** + * Convert a bit array to a SmallBitSet. Requires the bit array to contain exactly four bits. + */ + def bsToSmall(bits: Array[Long]): SmallBitSet = { + var a = -1 + var b = -1 + var c = -1 + var i = 0 + val end = bits.length * 64 + while (i < end) { + if (bsContains(bits, i)) { + if (a == -1) a = i + else if (b == -1) b = i + else if (c == -1) c = i + else return new SmallBitSet(a, b, c, i) + } + i += 1 + } + null + } + + /** + * An iterator that yields the elements that are in one bit set and not in another (&~). + */ + private class AndNotIt(setA: AliasSet, setB: AliasSet, thisAndOther: Array[Boolean]) extends IntIterator { + // values in the first bit set + private var a, b, c, d = -1 + private var xs: Array[Long] = null + + // values in the second bit set + private var notA, notB, notC, notD = -1 + private var notXs: Array[Long] = null + + // holds the next value of `x`, `y` or `z` that should be returned. assigned in hasNext + private var abcdNext = -1 + + // counts through elements in the `xs` bit set + private var i = 0 + // true if the current value of `i` should be returned by this iterator + private var iValid = false + + setA.set match { + case s: SmallBitSet => a = s.a; b = s.b; c = s.c; d = s.d + case bits: Array[Long] => xs = bits + } + + setB.set match { + case s: SmallBitSet => notA = s.a; notB = s.b; notC = s.c; notD = s.d + case bits: Array[Long] => notXs = bits + } + + // for each value that exists both in this AND (&) the other bit, `thisAndOther` is set to true. + // hacky side-effect, used for performance of AliasingFrame.merge. + private def setThisAndOther(x: Int) = if (thisAndOther != null) thisAndOther(x) = true + + private def checkABCD(x: Int, num: Int): Boolean = { + // assert(x == a && num == 1 || x == b && num == 2 || ...) + x != -1 && { + val otherHasA = x == notA || x == notB || x == notC || x == notD || (notXs != null && bsContains(notXs, x)) + if (otherHasA) setThisAndOther(x) + else abcdNext = x + (num: @switch) match { + case 1 => a = -1 + case 2 => b = -1 + case 3 => c = -1 + case 4 => d = -1 + } + !otherHasA + } + } + + // main performance hot spot + private def checkXs = { + (xs != null) && { + val end = xs.length * 64 + + while (i < end && { + val index = i >> 6 + if (xs(index) == 0l) { // boom. for nullness, this saves 35% of the overall analysis time. + i = ((index + 1) << 6) - 1 // -1 required because i is incremented in the loop body + true + } else { + val mask = 1l << i + // if (mask > xs(index)) we could also advance i to the next value, but that didn't pay off in benchmarks + val thisHasI = (xs(index) & mask) != 0l + !thisHasI || { + val otherHasI = i == notA || i == notB || i == notC || i == notD || (notXs != null && index < notXs.length && (notXs(index) & mask) != 0l) + if (otherHasI) setThisAndOther(i) + otherHasI + } + } + }) i += 1 + + iValid = i < end + iValid + } + } + + // this is the main hot spot of alias analysis. for nullness, 38% of the overall analysis time + // is spent here. within hasNext, almost the entire time is spent in `checkXs`. + // + def hasNext: Boolean = iValid || abcdNext != -1 || checkABCD(a, 1) || checkABCD(b, 2) || checkABCD(c, 3) || checkABCD(d, 4) || checkXs + + def next(): Int = { + if (hasNext) { + if (abcdNext != -1) { + val r = abcdNext; abcdNext = -1; r + } else { + val r = i; i += 1; iValid = false; r + } + } else Iterator.empty.next() + } + } + +// The number of bits in a bit array. Useful for debugging. +// def bsSize(bits: Array[Long]) = { +// var r = 0 +// var i = 0 +// while (i < bits.length) { +// r += java.lang.Long.bitCount(bits(i)) +// i += 1 +// } +// r +// } + + /** + * An iterator returning the elements in a that are not also in b (a &~ b). + * + * If `thisAndOther` is non-null, the iterator sets thisAndOther(i) to true for every value that + * is both in a and b (&). + */ + def andNotIterator(a: AliasSet, b: AliasSet, thisAndOther: Array[Boolean]): IntIterator = new AndNotIt(a, b, thisAndOther) +} diff --git a/src/compiler/scala/tools/nsc/backend/jvm/analysis/BackendUtils.scala b/src/compiler/scala/tools/nsc/backend/jvm/analysis/BackendUtils.scala new file mode 100644 index 0000000000..90da570f01 --- /dev/null +++ b/src/compiler/scala/tools/nsc/backend/jvm/analysis/BackendUtils.scala @@ -0,0 +1,514 @@ +package scala.tools.nsc +package backend.jvm +package analysis + +import java.lang.invoke.LambdaMetafactory + +import scala.annotation.switch +import scala.collection.JavaConverters._ +import scala.collection.mutable +import scala.tools.asm.Opcodes._ +import scala.tools.asm.tree._ +import scala.tools.asm.tree.analysis._ +import scala.tools.asm.{Handle, Type} +import scala.tools.nsc.backend.jvm.BTypes._ +import scala.tools.nsc.backend.jvm.GenBCode._ +import scala.tools.nsc.backend.jvm.opt.BytecodeUtils._ + +/** + * This component hosts tools and utilities used in the backend that require access to a `BTypes` + * instance. + * + * One example is the AsmAnalyzer class, which runs `computeMaxLocalsMaxStack` on the methodNode to + * be analyzed. This method in turn lives inside the BTypes assembly because it queries the per-run + * cache `maxLocalsMaxStackComputed` defined in there. + */ +class BackendUtils[BT <: BTypes](val btypes: BT) { + import btypes._ + import btypes.coreBTypes._ + import callGraph.ClosureInstantiation + + /** + * A wrapper to make ASM's Analyzer a bit easier to use. + */ + class AsmAnalyzer[V <: Value](methodNode: MethodNode, classInternalName: InternalName, val analyzer: Analyzer[V] = new Analyzer(new BasicInterpreter)) { + computeMaxLocalsMaxStack(methodNode) + try { + analyzer.analyze(classInternalName, methodNode) + } catch { + case ae: AnalyzerException => + throw new AnalyzerException(null, "While processing " + classInternalName + "." + methodNode.name, ae) + } + def frameAt(instruction: AbstractInsnNode): Frame[V] = analyzer.frameAt(instruction, methodNode) + } + + /** + * See the doc comment on package object `analysis` for a discussion on performance. + */ + object AsmAnalyzer { + // jvm limit is 65535 for both number of instructions and number of locals + + private def size(method: MethodNode) = method.instructions.size.toLong * method.maxLocals * method.maxLocals + + // with the limits below, analysis should not take more than one second + + private val nullnessSizeLimit = 5000l * 600l * 600l // 5000 insns, 600 locals + private val basicValueSizeLimit = 9000l * 1000l * 1000l + private val sourceValueSizeLimit = 8000l * 950l * 950l + + def sizeOKForAliasing(method: MethodNode): Boolean = size(method) < nullnessSizeLimit + def sizeOKForNullness(method: MethodNode): Boolean = size(method) < nullnessSizeLimit + def sizeOKForBasicValue(method: MethodNode): Boolean = size(method) < basicValueSizeLimit + def sizeOKForSourceValue(method: MethodNode): Boolean = size(method) < sourceValueSizeLimit + } + + class ProdConsAnalyzer(val methodNode: MethodNode, classInternalName: InternalName) extends AsmAnalyzer(methodNode, classInternalName, new Analyzer(new InitialProducerSourceInterpreter)) with ProdConsAnalyzerImpl + + class NonLubbingTypeFlowAnalyzer(val methodNode: MethodNode, classInternalName: InternalName) extends AsmAnalyzer(methodNode, classInternalName, new Analyzer(new NonLubbingTypeFlowInterpreter)) + + /** + * Add: + * private static Object $deserializeLambda$(SerializedLambda l) { + * return indy[scala.runtime.LambdaDeserialize.bootstrap](l) + * } + * + * We use invokedynamic here to enable caching within the deserializer without needing to + * host a static field in the enclosing class. This allows us to add this method to interfaces + * that define lambdas in default methods. + */ + def addLambdaDeserialize(classNode: ClassNode, implMethods: Iterable[Handle]): Unit = { + val cw = classNode + + // Make sure to reference the ClassBTypes of all types that are used in the code generated + // here (e.g. java/util/Map) are initialized. Initializing a ClassBType adds it to the + // `classBTypeFromInternalName` map. When writing the classfile, the asm ClassWriter computes + // stack map frames and invokes the `getCommonSuperClass` method. This method expects all + // ClassBTypes mentioned in the source code to exist in the map. + + val nilLookupDesc = MethodBType(Nil, jliMethodHandlesLookupRef).descriptor + val serlamObjDesc = MethodBType(jliSerializedLambdaRef :: Nil, ObjectRef).descriptor + + { + val mv = cw.visitMethod(ACC_PRIVATE + ACC_STATIC + ACC_SYNTHETIC, "$deserializeLambda$", serlamObjDesc, null, null) + mv.visitCode() + mv.visitVarInsn(ALOAD, 0) + mv.visitInvokeDynamicInsn("lambdaDeserialize", serlamObjDesc, lambdaDeserializeBootstrapHandle, implMethods.toArray: _*) + mv.visitInsn(ARETURN) + mv.visitEnd() + } + } + + /** + * Clone the instructions in `methodNode` into a new [[InsnList]], mapping labels according to + * the `labelMap`. Returns the new instruction list and a map from old to new instructions, and + * a list of lambda implementation methods references by invokedynamic[LambdaMetafactory] for a + * serializable SAM types. + */ + def cloneInstructions(methodNode: MethodNode, labelMap: Map[LabelNode, LabelNode], keepLineNumbers: Boolean): (InsnList, Map[AbstractInsnNode, AbstractInsnNode], List[Handle]) = { + val javaLabelMap = labelMap.asJava + val result = new InsnList + var map = Map.empty[AbstractInsnNode, AbstractInsnNode] + var inlinedTargetHandles = mutable.ListBuffer[Handle]() + for (ins <- methodNode.instructions.iterator.asScala) { + ins match { + case callGraph.LambdaMetaFactoryCall(indy, _, _, _) => indy.bsmArgs match { + case Array(_, targetHandle: Handle, _, flags: Integer, xs@_*) if (flags.intValue & LambdaMetafactory.FLAG_SERIALIZABLE) != 0 => + inlinedTargetHandles += targetHandle + case _ => + } + case _ => + } + if (keepLineNumbers || !ins.isInstanceOf[LineNumberNode]) { + val cloned = ins.clone(javaLabelMap) + result add cloned + map += ((ins, cloned)) + } + } + (result, map, inlinedTargetHandles.toList) + } + + def getBoxedUnit: FieldInsnNode = new FieldInsnNode(GETSTATIC, srBoxedUnitRef.internalName, "UNIT", srBoxedUnitRef.descriptor) + + private val anonfunAdaptedName = """.*\$anonfun\$.*\$\d+\$adapted""".r + def hasAdaptedImplMethod(closureInit: ClosureInstantiation): Boolean = { + anonfunAdaptedName.pattern.matcher(closureInit.lambdaMetaFactoryCall.implMethod.getName).matches + } + + private def primitiveAsmTypeToBType(primitiveType: Type): PrimitiveBType = (primitiveType.getSort: @switch) match { + case Type.BOOLEAN => BOOL + case Type.BYTE => BYTE + case Type.CHAR => CHAR + case Type.SHORT => SHORT + case Type.INT => INT + case Type.LONG => LONG + case Type.FLOAT => FLOAT + case Type.DOUBLE => DOUBLE + case _ => null + } + + def isScalaBox(insn: MethodInsnNode): Boolean = { + insn.owner == srBoxesRunTimeRef.internalName && { + val args = Type.getArgumentTypes(insn.desc) + args.length == 1 && (srBoxesRuntimeBoxToMethods.get(primitiveAsmTypeToBType(args(0))) match { + case Some(MethodNameAndType(name, tp)) => name == insn.name && tp.descriptor == insn.desc + case _ => false + }) + } + } + + def getScalaBox(primitiveType: Type): MethodInsnNode = { + val bType = primitiveAsmTypeToBType(primitiveType) + val MethodNameAndType(name, methodBType) = srBoxesRuntimeBoxToMethods(bType) + new MethodInsnNode(INVOKESTATIC, srBoxesRunTimeRef.internalName, name, methodBType.descriptor, /*itf =*/ false) + } + + def isScalaUnbox(insn: MethodInsnNode): Boolean = { + insn.owner == srBoxesRunTimeRef.internalName && (srBoxesRuntimeUnboxToMethods.get(primitiveAsmTypeToBType(Type.getReturnType(insn.desc))) match { + case Some(MethodNameAndType(name, tp)) => name == insn.name && tp.descriptor == insn.desc + case _ => false + }) + } + + def getScalaUnbox(primitiveType: Type): MethodInsnNode = { + val bType = primitiveAsmTypeToBType(primitiveType) + val MethodNameAndType(name, methodBType) = srBoxesRuntimeUnboxToMethods(bType) + new MethodInsnNode(INVOKESTATIC, srBoxesRunTimeRef.internalName, name, methodBType.descriptor, /*itf =*/ false) + } + + private def calleeInMap(insn: MethodInsnNode, map: Map[InternalName, MethodNameAndType]): Boolean = map.get(insn.owner) match { + case Some(MethodNameAndType(name, tp)) => insn.name == name && insn.desc == tp.descriptor + case _ => false + } + + def isJavaBox(insn: MethodInsnNode): Boolean = calleeInMap(insn, javaBoxMethods) + def isJavaUnbox(insn: MethodInsnNode): Boolean = calleeInMap(insn, javaUnboxMethods) + + def isPredefAutoBox(insn: MethodInsnNode): Boolean = { + insn.owner == PredefRef.internalName && (predefAutoBoxMethods.get(insn.name) match { + case Some(tp) => insn.desc == tp.descriptor + case _ => false + }) + } + + def isPredefAutoUnbox(insn: MethodInsnNode): Boolean = { + insn.owner == PredefRef.internalName && (predefAutoUnboxMethods.get(insn.name) match { + case Some(tp) => insn.desc == tp.descriptor + case _ => false + }) + } + + def isRefCreate(insn: MethodInsnNode): Boolean = calleeInMap(insn, srRefCreateMethods) + def isRefZero(insn: MethodInsnNode): Boolean = calleeInMap(insn, srRefZeroMethods) + + def runtimeRefClassBoxedType(refClass: InternalName): Type = Type.getArgumentTypes(srRefCreateMethods(refClass).methodType.descriptor)(0) + + def isSideEffectFreeCall(insn: MethodInsnNode): Boolean = { + isScalaBox(insn) || isScalaUnbox(insn) || + isJavaBox(insn) || // not java unbox, it may NPE + isSideEffectFreeConstructorCall(insn) + } + + def isNonNullMethodInvocation(mi: MethodInsnNode): Boolean = { + isJavaBox(mi) || isScalaBox(mi) || isPredefAutoBox(mi) || isRefCreate(mi) || isRefZero(mi) + } + + def isModuleLoad(insn: AbstractInsnNode, moduleName: InternalName): Boolean = insn match { + case fi: FieldInsnNode => fi.getOpcode == GETSTATIC && fi.owner == moduleName && fi.name == "MODULE$" && fi.desc == ("L" + moduleName + ";") + case _ => false + } + + def isPredefLoad(insn: AbstractInsnNode) = isModuleLoad(insn, PredefRef.internalName) + + def isPrimitiveBoxConstructor(insn: MethodInsnNode): Boolean = calleeInMap(insn, primitiveBoxConstructors) + def isRuntimeRefConstructor(insn: MethodInsnNode): Boolean = calleeInMap(insn, srRefConstructors) + def isTupleConstructor(insn: MethodInsnNode): Boolean = calleeInMap(insn, tupleClassConstructors) + + // unused objects created by these constructors are eliminated by pushPop + private lazy val sideEffectFreeConstructors: Set[(String, String)] = { + val ownerDesc = (p: (InternalName, MethodNameAndType)) => (p._1, p._2.methodType.descriptor) + primitiveBoxConstructors.map(ownerDesc).toSet ++ + srRefConstructors.map(ownerDesc) ++ + tupleClassConstructors.map(ownerDesc) ++ Set( + (ObjectRef.internalName, MethodBType(Nil, UNIT).descriptor), + (StringRef.internalName, MethodBType(Nil, UNIT).descriptor), + (StringRef.internalName, MethodBType(List(StringRef), UNIT).descriptor), + (StringRef.internalName, MethodBType(List(ArrayBType(CHAR)), UNIT).descriptor)) + } + + def isSideEffectFreeConstructorCall(insn: MethodInsnNode): Boolean = { + insn.name == INSTANCE_CONSTRUCTOR_NAME && sideEffectFreeConstructors((insn.owner, insn.desc)) + } + + private lazy val classesOfSideEffectFreeConstructors = sideEffectFreeConstructors.map(_._1) + + def isNewForSideEffectFreeConstructor(insn: AbstractInsnNode) = { + insn.getOpcode == NEW && { + val ti = insn.asInstanceOf[TypeInsnNode] + classesOfSideEffectFreeConstructors.contains(ti.desc) + } + } + + def isBoxedUnit(insn: AbstractInsnNode) = { + insn.getOpcode == GETSTATIC && { + val fi = insn.asInstanceOf[FieldInsnNode] + fi.owner == srBoxedUnitRef.internalName && fi.name == "UNIT" && fi.desc == srBoxedUnitRef.descriptor + } + } + + /** + * Visit the class node and collect all referenced nested classes. + */ + def collectNestedClasses(classNode: ClassNode): List[ClassBType] = { + val innerClasses = mutable.Set.empty[ClassBType] + + def visitInternalName(internalName: InternalName): Unit = if (internalName != null) { + val t = classBTypeFromParsedClassfile(internalName) + if (t.isNestedClass.get) innerClasses += t + } + + // either an internal/Name or [[Linternal/Name; -- there are certain references in classfiles + // that are either an internal name (without the surrounding `L;`) or an array descriptor + // `[Linternal/Name;`. + def visitInternalNameOrArrayReference(ref: String): Unit = if (ref != null) { + val bracket = ref.lastIndexOf('[') + if (bracket == -1) visitInternalName(ref) + else if (ref.charAt(bracket + 1) == 'L') visitInternalName(ref.substring(bracket + 2, ref.length - 1)) + } + + // we are only interested in the class references in the descriptor, so we can skip over + // primitives and the brackets of array descriptors + def visitDescriptor(desc: String): Unit = (desc.charAt(0): @switch) match { + case '(' => + val internalNames = mutable.ListBuffer.empty[String] + var i = 1 + while (i < desc.length) { + if (desc.charAt(i) == 'L') { + val start = i + 1 // skip the L + while (desc.charAt(i) != ';') i += 1 + internalNames append desc.substring(start, i) + } + // skips over '[', ')', primitives + i += 1 + } + internalNames foreach visitInternalName + + case 'L' => + visitInternalName(desc.substring(1, desc.length - 1)) + + case '[' => + visitInternalNameOrArrayReference(desc) + + case _ => // skip over primitive types + } + + def visitConstant(const: AnyRef): Unit = const match { + case t: Type => visitDescriptor(t.getDescriptor) + case _ => + } + + // in principle we could references to annotation types, as they only end up as strings in the + // constant pool, not as class references. however, the java compiler still includes nested + // annotation classes in the innerClass table, so we do the same. explained in detail in the + // large comment in class BTypes. + def visitAnnotation(annot: AnnotationNode): Unit = { + visitDescriptor(annot.desc) + if (annot.values != null) annot.values.asScala foreach visitConstant + } + + def visitAnnotations(annots: java.util.List[_ <: AnnotationNode]) = if (annots != null) annots.asScala foreach visitAnnotation + def visitAnnotationss(annotss: Array[java.util.List[AnnotationNode]]) = if (annotss != null) annotss foreach visitAnnotations + + def visitHandle(handle: Handle): Unit = { + visitInternalNameOrArrayReference(handle.getOwner) + visitDescriptor(handle.getDesc) + } + + visitInternalName(classNode.name) + innerClasses ++= classBTypeFromParsedClassfile(classNode.name).info.get.nestedClasses + + visitInternalName(classNode.superName) + classNode.interfaces.asScala foreach visitInternalName + visitInternalName(classNode.outerClass) + + visitAnnotations(classNode.visibleAnnotations) + visitAnnotations(classNode.visibleTypeAnnotations) + visitAnnotations(classNode.invisibleAnnotations) + visitAnnotations(classNode.invisibleTypeAnnotations) + + for (f <- classNode.fields.asScala) { + visitDescriptor(f.desc) + visitAnnotations(f.visibleAnnotations) + visitAnnotations(f.visibleTypeAnnotations) + visitAnnotations(f.invisibleAnnotations) + visitAnnotations(f.invisibleTypeAnnotations) + } + + for (m <- classNode.methods.asScala) { + visitDescriptor(m.desc) + + visitAnnotations(m.visibleAnnotations) + visitAnnotations(m.visibleTypeAnnotations) + visitAnnotations(m.invisibleAnnotations) + visitAnnotations(m.invisibleTypeAnnotations) + visitAnnotationss(m.visibleParameterAnnotations) + visitAnnotationss(m.invisibleParameterAnnotations) + visitAnnotations(m.visibleLocalVariableAnnotations) + visitAnnotations(m.invisibleLocalVariableAnnotations) + + m.exceptions.asScala foreach visitInternalName + for (tcb <- m.tryCatchBlocks.asScala) visitInternalName(tcb.`type`) + + val iter = m.instructions.iterator() + while (iter.hasNext) iter.next() match { + case ti: TypeInsnNode => visitInternalNameOrArrayReference(ti.desc) + case fi: FieldInsnNode => visitInternalNameOrArrayReference(fi.owner); visitDescriptor(fi.desc) + case mi: MethodInsnNode => visitInternalNameOrArrayReference(mi.owner); visitDescriptor(mi.desc) + case id: InvokeDynamicInsnNode => visitDescriptor(id.desc); visitHandle(id.bsm); id.bsmArgs foreach visitConstant + case ci: LdcInsnNode => visitConstant(ci.cst) + case ma: MultiANewArrayInsnNode => visitDescriptor(ma.desc) + case _ => + } + } + innerClasses.toList + } + + /** + * In order to run an Analyzer, the maxLocals / maxStack fields need to be available. The ASM + * framework only computes these values during bytecode generation. + * + * NOTE 1: as explained in the `analysis` package object, the maxStack value used by the Analyzer + * may be smaller than the correct maxStack value in the classfile (Analyzers only use a single + * slot for long / double values). The maxStack computed here are correct for running an analyzer, + * but not for writing in the classfile. We let the ClassWriter recompute max's. + * + * NOTE 2: the maxStack value computed here may be larger than the smallest correct value + * that would allow running an analyzer, see `InstructionStackEffect.forAsmAnalysis` and + * `InstructionStackEffect.maxStackGrowth`. + * + * NOTE 3: the implementation doesn't look at instructions that cannot be reached, it computes + * the max local / stack size in the reachable code. These max's work just fine for running an + * Analyzer: its implementation also skips over unreachable code in the same way. + */ + def computeMaxLocalsMaxStack(method: MethodNode): Unit = { + if (isAbstractMethod(method) || isNativeMethod(method)) { + method.maxLocals = 0 + method.maxStack = 0 + } else if (!maxLocalsMaxStackComputed(method)) { + val size = method.instructions.size + + var maxLocals = parametersSize(method) + var maxStack = 0 + + // queue of instruction indices where analysis should start + var queue = new Array[Int](8) + var top = -1 + def enq(i: Int): Unit = { + if (top == queue.length - 1) { + val nq = new Array[Int](queue.length * 2) + Array.copy(queue, 0, nq, 0, queue.length) + queue = nq + } + top += 1 + queue(top) = i + } + def deq(): Int = { + val r = queue(top) + top -= 1 + r + } + + val subroutineRetTargets = new mutable.Stack[AbstractInsnNode] + + // for each instruction in the queue, contains the stack height at this instruction. + // once an instruction has been treated, contains -1 to prevent re-enqueuing + val stackHeights = new Array[Int](size) + + def enqInsn(insn: AbstractInsnNode, height: Int): Unit = { + enqInsnIndex(method.instructions.indexOf(insn), height) + } + + def enqInsnIndex(insnIndex: Int, height: Int): Unit = { + if (insnIndex < size && stackHeights(insnIndex) != -1) { + stackHeights(insnIndex) = height + enq(insnIndex) + } + } + + val tcbIt = method.tryCatchBlocks.iterator() + while (tcbIt.hasNext) { + val tcb = tcbIt.next() + enqInsn(tcb.handler, 1) + if (maxStack == 0) maxStack = 1 + } + + enq(0) + while (top != -1) { + val insnIndex = deq() + val insn = method.instructions.get(insnIndex) + val initHeight = stackHeights(insnIndex) + stackHeights(insnIndex) = -1 // prevent i from being enqueued again + + if (insn.getOpcode == -1) { // frames, labels, line numbers + enqInsnIndex(insnIndex + 1, initHeight) + } else { + val stackGrowth = InstructionStackEffect.maxStackGrowth(insn) + val heightAfter = initHeight + stackGrowth + if (heightAfter > maxStack) maxStack = heightAfter + + // update maxLocals + insn match { + case v: VarInsnNode => + val longSize = if (isSize2LoadOrStore(v.getOpcode)) 1 else 0 + maxLocals = math.max(maxLocals, v.`var` + longSize + 1) // + 1 because local numbers are 0-based + + case i: IincInsnNode => + maxLocals = math.max(maxLocals, i.`var` + 1) + + case _ => + } + + insn match { + case j: JumpInsnNode => + if (j.getOpcode == JSR) { + val jsrTargetHeight = heightAfter + 1 + if (jsrTargetHeight > maxStack) maxStack = jsrTargetHeight + subroutineRetTargets.push(j.getNext) + enqInsn(j.label, jsrTargetHeight) + } else { + enqInsn(j.label, heightAfter) + val opc = j.getOpcode + if (opc != GOTO) enqInsnIndex(insnIndex + 1, heightAfter) // jump is conditional, so the successor is also a possible control flow target + } + + case l: LookupSwitchInsnNode => + var j = 0 + while (j < l.labels.size) { + enqInsn(l.labels.get(j), heightAfter); j += 1 + } + enqInsn(l.dflt, heightAfter) + + case t: TableSwitchInsnNode => + var j = 0 + while (j < t.labels.size) { + enqInsn(t.labels.get(j), heightAfter); j += 1 + } + enqInsn(t.dflt, heightAfter) + + case r: VarInsnNode if r.getOpcode == RET => + enqInsn(subroutineRetTargets.pop(), heightAfter) + + case _ => + val opc = insn.getOpcode + if (opc != ATHROW && !isReturn(insn)) + enqInsnIndex(insnIndex + 1, heightAfter) + } + } + } + + method.maxLocals = maxLocals + method.maxStack = maxStack + + maxLocalsMaxStackComputed += method + } + } +} diff --git a/src/compiler/scala/tools/nsc/backend/jvm/analysis/InstructionStackEffect.scala b/src/compiler/scala/tools/nsc/backend/jvm/analysis/InstructionStackEffect.scala index 8d8ea839e6..dd19ad594f 100644 --- a/src/compiler/scala/tools/nsc/backend/jvm/analysis/InstructionStackEffect.scala +++ b/src/compiler/scala/tools/nsc/backend/jvm/analysis/InstructionStackEffect.scala @@ -5,35 +5,74 @@ package analysis import scala.annotation.switch import scala.tools.asm.Opcodes._ import scala.tools.asm.Type -import scala.tools.asm.tree.{MultiANewArrayInsnNode, InvokeDynamicInsnNode, MethodInsnNode, AbstractInsnNode} +import scala.tools.asm.tree._ import scala.tools.asm.tree.analysis.{Frame, Value} import opt.BytecodeUtils._ -import collection.immutable object InstructionStackEffect { - private var cache: immutable.IntMap[(Int, Int)] = immutable.IntMap.empty - private def t(x: Int, y: Int): (Int, Int) = { - // x can go up to 255 (number of parameters of a method, dimensions in multianewarray) we cache - // x up to 10, which covers most cases and limits the cache. y doesn't go above 6 (see cases). - if (x > 10 || y > 6) (x, y) - else { - val key = (x << 8) + y // this would work for any x < 256 - if (cache contains key) { - cache(key) - } else { - val r = (x, y) - cache += key -> r - r - } - } + val consShift = 3 + val prodMask = (1 << consShift) - 1 + + def cons(i: Int) = i >>> consShift + def prod(i: Int) = i & prodMask + + private def t(x: Int, y: Int): Int = (x << consShift) | y + + /** + * Returns the number of stack values consumed and produced by `insn`, encoded in a single `Int` + * (the `cons` / `prod` extract individual values). The returned values are correct for use in + * asm's Analyzer framework. For example, a LLOAD instruction produces one stack value. See also + * doc in `analysis` package object. + * + * This method requires the `frame` to be in the state **before** executing / interpreting the + * `insn`. + */ + def forAsmAnalysis[V <: Value](insn: AbstractInsnNode, frame: Frame[V]): Int = computeConsProd(insn, forClassfile = false, conservative = false, frame = frame) + + /** + * Returns the maximal possible growth of the stack when executing `insn`. The returned value + * is usually the same as expected by asm's Analyzer framework, but it may be larger. For + * example, consider a POP2 instruction: + * - if two size-1 values are popped, then the asm Analyzer consumes two values + * - if a size-2 value is popped, the asm Analyzer consumes only one stack slot (see doc in the + * `analysis` package object) + * + * If a precise result is needed, invoke the `forAsmAnalysis` and provide a `frame` value that + * allows looking up the sizes of values on the stack. + */ + def maxStackGrowth(insn: AbstractInsnNode): Int = { + val prodCons = computeConsProd(insn, forClassfile = false, conservative = true) + prod(prodCons) - cons(prodCons) } /** - * Returns a pair with the number of stack values consumed and produced by `insn`. - * This method requires the `frame` to be in the state **before** executing / interpreting - * the `insn`. + * Returns the number of stack values consumed and produced by `insn`, encoded in a single `Int` + * (the `cons` / `prod` extract individual values). The returned values are correct for writing + * into a classfile (see doc on the `analysis` package object). */ - def apply[V <: Value](insn: AbstractInsnNode, frame: Frame[V]): (Int, Int) = { + def forClassfile(insn: AbstractInsnNode): Int = computeConsProd(insn, forClassfile = true, conservative = false) + + private def invokeConsProd(methodDesc: String, insn: AbstractInsnNode, forClassfile: Boolean): Int = { + val consumesReceiver = insn.getOpcode != INVOKESTATIC && insn.getOpcode != INVOKEDYNAMIC + if (forClassfile) { + val sizes = Type.getArgumentsAndReturnSizes(methodDesc) + val cons = (sizes >> 2) - (if (consumesReceiver) 0 else 1) + val prod = sizes & 0x03 + t(cons, prod) + } else { + val cons = Type.getArgumentTypes(methodDesc).length + (if (consumesReceiver) 1 else 0) + val prod = if (Type.getReturnType(methodDesc) == Type.VOID_TYPE) 0 else 1 + t(cons, prod) + } + } + + private def fieldInsnIsLongOrDouble(insn: AbstractInsnNode) = { + val d = insn.asInstanceOf[FieldInsnNode].desc + d == "J" || d == "D" + } + + private def computeConsProd[V <: Value](insn: AbstractInsnNode, forClassfile: Boolean, conservative: Boolean, frame: Frame[V] = null): Int = { + // not used if `forClassfile || conservative`: in these cases, `frame` is allowed to be `null` def peekStack(n: Int): V = frame.peekStack(n) (insn.getOpcode: @switch) match { @@ -48,142 +87,176 @@ object InstructionStackEffect { ICONST_3 | ICONST_4 | ICONST_5 | - LCONST_0 | - LCONST_1 | FCONST_0 | FCONST_1 | FCONST_2 | - DCONST_0 | - DCONST_1 | BIPUSH | SIPUSH | - LDC | ILOAD | - LLOAD | FLOAD | - DLOAD | ALOAD => t(0, 1) + case LDC => + if (forClassfile) insn.asInstanceOf[LdcInsnNode].cst match { + case _: java.lang.Long | _: java.lang.Double => t(0, 2) + case _ => t(0, 1) + } else + t(0, 1) + + case LCONST_0 | + LCONST_1 | + DCONST_0 | + DCONST_1 | + LLOAD | + DLOAD => if (forClassfile) t(0, 2) else t(0, 1) + case IALOAD | - LALOAD | FALOAD | - DALOAD | AALOAD | BALOAD | CALOAD | SALOAD => t(2, 1) + case LALOAD | + DALOAD => if (forClassfile) t(2, 2) else t(2, 1) + case ISTORE | - LSTORE | FSTORE | - DSTORE | ASTORE => t(1, 0) + case LSTORE | + DSTORE => if (forClassfile) t(2, 0) else t(1, 0) + case IASTORE | - LASTORE | FASTORE | - DASTORE | AASTORE | BASTORE | CASTORE | SASTORE => t(3, 0) + case LASTORE | + DASTORE => if (forClassfile) t(4, 0) else t(3, 0) + case POP => t(1, 0) case POP2 => - val isSize2 = peekStack(0).getSize == 2 - if (isSize2) t(1, 0) else t(2, 0) + if (forClassfile) t(2, 0) + else if (conservative) t(1, 0) + else { + val isSize2 = peekStack(0).getSize == 2 + if (isSize2) t(1, 0) else t(2, 0) + } case DUP => t(1, 2) case DUP_X1 => t(2, 3) case DUP_X2 => - val isSize2 = peekStack(1).getSize == 2 - if (isSize2) t(2, 3) else t(3, 4) + if (forClassfile || conservative) t(3, 4) + else { + val isSize2 = peekStack(1).getSize == 2 + if (isSize2) t(2, 3) else t(3, 4) + } case DUP2 => - val isSize2 = peekStack(0).getSize == 2 - if (isSize2) t(1, 2) else t(2, 4) + if (forClassfile || conservative) t(2, 4) + else { + val isSize2 = peekStack(0).getSize == 2 + if (isSize2) t(1, 2) else t(2, 4) + } case DUP2_X1 => - val isSize2 = peekStack(0).getSize == 2 - if (isSize2) t(2, 3) else t(3, 4) + if (forClassfile || conservative) t(3, 5) + else { + val isSize2 = peekStack(0).getSize == 2 + if (isSize2) t(2, 3) else t(3, 5) + } case DUP2_X2 => - val v1isSize2 = peekStack(0).getSize == 2 - if (v1isSize2) { - val v2isSize2 = peekStack(1).getSize == 2 - if (v2isSize2) t(2, 3) else t(3, 4) - } else { - val v3isSize2 = peekStack(2).getSize == 2 - if (v3isSize2) t(3, 5) else t(4, 6) + if (forClassfile || conservative) t(4, 6) + else { + val v1isSize2 = peekStack(0).getSize == 2 + if (v1isSize2) { + val v2isSize2 = peekStack(1).getSize == 2 + if (v2isSize2) t(2, 3) else t(3, 4) + } else { + val v3isSize2 = peekStack(2).getSize == 2 + if (v3isSize2) t(3, 5) else t(4, 6) + } } case SWAP => t(2, 2) case IADD | - LADD | FADD | - DADD | ISUB | - LSUB | FSUB | - DSUB | IMUL | - LMUL | FMUL | - DMUL | IDIV | - LDIV | FDIV | - DDIV | IREM | + FREM => t(2, 1) + + case LADD | + DADD | + LSUB | + DSUB | + LMUL | + DMUL | + LDIV | + DDIV | LREM | - FREM | - DREM => t(2, 1) + DREM => if (forClassfile) t(4, 2) else t(2, 1) case INEG | - LNEG | - FNEG | - DNEG => t(1, 1) + FNEG => t(1, 1) + + case LNEG | + DNEG => if (forClassfile) t(2, 2) else t(1, 1) case ISHL | - LSHL | ISHR | - LSHR | IUSHR | - LUSHR | IAND | - LAND | IOR | + IXOR => t(2, 1) + + case LSHL | + LSHR | + LUSHR => if (forClassfile) t(3, 2) else t(2, 1) + + case LAND | LOR | - IXOR | - LXOR => t(2, 1) + LXOR => if (forClassfile) t(4, 2) else t(2, 1) case IINC => t(0, 0) - case I2L | - I2F | - I2D | - L2I | - L2F | - L2D | + case I2F | F2I | - F2L | - F2D | - D2I | - D2L | - D2F | I2B | I2C | I2S => t(1, 1) + case I2L | + I2D | + F2L | + F2D => if (forClassfile) t(1, 2) else t(1, 1) + + case L2I | + L2F | + D2I | + D2F => if (forClassfile) t(2, 1) else t(1, 1) + + case L2D | + D2L => if (forClassfile) t(2, 2) else t(1, 1) + + case FCMPL | + FCMPG => t(2, 1) + case LCMP | - FCMPL | - FCMPG | DCMPL | - DCMPG => t(2, 1) + DCMPG => if (forClassfile) t(4, 1) else t(2, 1) case IFEQ | IFNE | @@ -211,35 +284,36 @@ object InstructionStackEffect { LOOKUPSWITCH => t(1, 0) case IRETURN | - LRETURN | FRETURN | - DRETURN | ARETURN => t(1, 0) // Frame.execute consumes one stack value + case LRETURN | + DRETURN => if (forClassfile) t(2, 0) else t(1, 0) + case RETURN => t(0, 0) // Frame.execute does not change the stack - case GETSTATIC => t(0, 1) + case GETSTATIC => + val prod = if (forClassfile && fieldInsnIsLongOrDouble(insn)) 2 else 1 + t(0, prod) - case PUTSTATIC => t(1, 0) + case PUTSTATIC => + val cons = if (forClassfile && fieldInsnIsLongOrDouble(insn)) 2 else 1 + t(cons, 0) - case GETFIELD => t(1, 1) + case GETFIELD => + val prod = if (forClassfile && fieldInsnIsLongOrDouble(insn)) 2 else 1 + t(1, prod) - case PUTFIELD => t(2, 0) + case PUTFIELD => + val cons = if (forClassfile && fieldInsnIsLongOrDouble(insn)) 3 else 2 + t(cons, 0) case INVOKEVIRTUAL | INVOKESPECIAL | INVOKESTATIC | - INVOKEINTERFACE => - val desc = insn.asInstanceOf[MethodInsnNode].desc - val cons = Type.getArgumentTypes(desc).length + (if (insn.getOpcode == INVOKESTATIC) 0 else 1) - val prod = if (Type.getReturnType(desc) == Type.VOID_TYPE) 0 else 1 - t(cons, prod) - - case INVOKEDYNAMIC => - val desc = insn.asInstanceOf[InvokeDynamicInsnNode].desc - val cons = Type.getArgumentTypes(desc).length - val prod = if (Type.getReturnType(desc) == Type.VOID_TYPE) 0 else 1 - t(cons, prod) + INVOKEINTERFACE => invokeConsProd(insn.asInstanceOf[MethodInsnNode].desc, insn, forClassfile) + + case INVOKEDYNAMIC => invokeConsProd(insn.asInstanceOf[InvokeDynamicInsnNode].desc, insn, forClassfile) case NEW => t(0, 1) @@ -261,5 +335,4 @@ object InstructionStackEffect { IFNONNULL => t(1, 0) } } - } diff --git a/src/compiler/scala/tools/nsc/backend/jvm/analysis/NullnessAnalyzer.scala b/src/compiler/scala/tools/nsc/backend/jvm/analysis/NullnessAnalyzer.scala index 31b62f747e..01afd0d2ef 100644 --- a/src/compiler/scala/tools/nsc/backend/jvm/analysis/NullnessAnalyzer.scala +++ b/src/compiler/scala/tools/nsc/backend/jvm/analysis/NullnessAnalyzer.scala @@ -5,68 +5,14 @@ package analysis import java.util import scala.annotation.switch -import scala.tools.asm.{Type, Opcodes} -import scala.tools.asm.tree.{MethodInsnNode, LdcInsnNode, AbstractInsnNode} -import scala.tools.asm.tree.analysis.{Frame, Analyzer, Interpreter, Value} +import scala.tools.asm.{Opcodes, Type} +import scala.tools.asm.tree.{AbstractInsnNode, LdcInsnNode, MethodInsnNode, MethodNode} +import scala.tools.asm.tree.analysis._ import scala.tools.nsc.backend.jvm.opt.BytecodeUtils import BytecodeUtils._ /** - * Some notes on the ASM analyzer framework. - * - * Value - * - Abstract, needs to be implemented for each analysis. - * - Represents the desired information about local variables and stack values, for example: - * - Is this value known to be null / not null? - * - What are the instructions that could potentially have produced this value? - * - * Interpreter - * - Abstract, needs to be implemented for each analysis. Sometimes one can subclass an existing - * interpreter, e.g., SourceInterpreter or BasicInterpreter. - * - Multiple abstract methods that receive an instruction and the instruction's input values, and - * return a value representing the result of that instruction. - * - Note: due to control flow, the interpreter can be invoked multiple times for the same - * instruction, until reaching a fixed point. - * - Abstract `merge` function that computes the least upper bound of two values. Used by - * Frame.merge (see below). - * - * Frame - * - Can be used directly for many analyses, no subclass required. - * - Every frame has an array of values: one for each local variable and for each stack slot. - * - A `top` index stores the index of the current stack top - * - NOTE: for a size-2 local variable at index i, the local variable at i+1 is set to an empty - * value. However, for a size-2 value at index i on the stack, the value at i+1 holds the next - * stack value. - * - Defines the `execute(instruction)` method. - * - executing mutates the state of the frame according to the effect of the instruction - * - pop consumed values from the stack - * - pass them to the interpreter together with the instruction - * - if applicable, push the resulting value on the stack - * - Defines the `merge(otherFrame)` method - * - called by the analyzer when multiple control flow paths lead to an instruction - * - the frame at the branching instruction is merged into the current frame of the - * instruction (held by the analyzer) - * - mutates the values of the current frame, merges all values using interpreter.merge. - * - * Analyzer - * - Stores a frame for each instruction - * - `merge` function takes an instruction and a frame, merges the existing frame for that instr - * (from the frames array) with the new frame passed as argument. - * if the frame changed, puts the instruction on the work queue (fixpiont). - * - initial frame: initialized for first instr by calling interpreter.new[...]Value - * for each slot (locals and params), stored in frames[firstInstr] by calling `merge` - * - work queue of instructions (`queue` array, `top` index for next instruction to analyze) - * - analyze(method): simulate control flow. while work queue non-empty: - * - copy the state of `frames[instr]` into a local frame `current` - * - call `current.execute(instr, interpreter)`, mutating the `current` frame - * - if it's a branching instruction - * - for all potential destination instructions - * - merge the destination instruction frame with the `current` frame - * (this enqueues the destination instr if its frame changed) - * - invoke `newControlFlowEdge` (see below) - * - the analyzer also tracks active exception handlers at each instruction - * - the empty method `newControlFlowEdge` can be overridden to track control flow if required - * + * See the package object `analysis` for details on the ASM analysis framework. * * Some notes on nullness analysis. * @@ -87,59 +33,37 @@ import BytecodeUtils._ */ /** - * Type to represent nullness of values. - */ -sealed trait Nullness { - final def merge(other: Nullness) = if (this == other) this else Unknown -} -case object NotNull extends Nullness -case object Unknown extends Nullness -case object Null extends Nullness - -/** * Represents the nullness state for a local variable or stack value. * - * Note that nullness of primitive values is not tracked, it will be always [[Unknown]]. + * Note that nullness of primitive values is not tracked, it will be always unknown. */ -sealed trait NullnessValue extends Value { - /** - * The nullness of this value. - */ - def nullness: Nullness - - /** - * True if this value is a long or double. The Analyzer framework needs to know - * the size of each value when interpreting instructions, see `Frame.execute`. - */ - def isSize2: Boolean +sealed abstract class NullnessValue(final val isSize2: Boolean) extends Value { /** * The size of the slot described by this value. Cannot be 0 because no values are allocated * for void-typed slots, see NullnessInterpreter.newValue. **/ def getSize: Int = if (isSize2) 2 else 1 - def merge(other: NullnessValue) = NullnessValue(nullness merge other.nullness, isSize2) + def merge(other: NullnessValue) = { + if (this eq other) this + else if (this eq UnknownValue2) this // the only possible value of size two + else UnknownValue1 + } + + final override def equals(other: Any) = this eq other.asInstanceOf[Object] } -object NullValue extends NullnessValue { def nullness = Null; def isSize2 = false; override def toString = "Null" } -object UnknownValue1 extends NullnessValue { def nullness = Unknown; def isSize2 = false; override def toString = "Unknown1" } -object UnknownValue2 extends NullnessValue { def nullness = Unknown; def isSize2 = true; override def toString = "Unknown2" } -object NotNullValue extends NullnessValue { def nullness = NotNull; def isSize2 = false; override def toString = "NotNull" } +object NullValue extends NullnessValue(isSize2 = false) { override def toString = "Null" } +object UnknownValue1 extends NullnessValue(isSize2 = false) { override def toString = "Unknown1" } +object UnknownValue2 extends NullnessValue(isSize2 = true ) { override def toString = "Unknown2" } +object NotNullValue extends NullnessValue(isSize2 = false) { override def toString = "NotNull" } object NullnessValue { - def apply(nullness: Nullness, isSize2: Boolean): NullnessValue = { - if (nullness == Null) NullValue - else if (nullness == NotNull) NotNullValue - else if (isSize2) UnknownValue2 - else UnknownValue1 - } - - def apply(nullness: Nullness, insn: AbstractInsnNode): NullnessValue = { - apply(nullness, isSize2 = BytecodeUtils.instructionResultSize(insn) == 2) - } + def unknown(isSize2: Boolean) = if (isSize2) UnknownValue2 else UnknownValue1 + def unknown(insn: AbstractInsnNode) = if (BytecodeUtils.instructionResultSize(insn) == 2) UnknownValue2 else UnknownValue1 } -final class NullnessInterpreter extends Interpreter[NullnessValue](Opcodes.ASM5) { +final class NullnessInterpreter(bTypes: BTypes, method: MethodNode) extends Interpreter[NullnessValue](Opcodes.ASM5) { def newValue(tp: Type): NullnessValue = { // ASM loves giving semantics to null. The behavior here is the same as in SourceInterpreter, // which is provided by the framework. @@ -151,29 +75,31 @@ final class NullnessInterpreter extends Interpreter[NullnessValue](Opcodes.ASM5) // (2) `tp` may also be `null`. When creating the initial frame, the analyzer invokes // `newValue(null)` for each local variable. We have to return a value of size 1. if (tp == Type.VOID_TYPE) null // (1) - else NullnessValue(Unknown, isSize2 = tp != null /*(2)*/ && tp.getSize == 2 ) + else NullnessValue.unknown(isSize2 = tp != null /*(2)*/ && tp.getSize == 2 ) } override def newParameterValue(isInstanceMethod: Boolean, local: Int, tp: Type): NullnessValue = { // For instance methods, the `this` parameter is known to be not null. - if (isInstanceMethod && local == 0) NullnessValue(NotNull, isSize2 = false) + val isThis = local == 0 && (isInstanceMethod || { + method.parameters != null && !method.parameters.isEmpty && { + val p = method.parameters.get(0) + (p.access & Opcodes.ACC_SYNTHETIC) != 0 && p.name == "$this" + } + }) + if (isThis) NotNullValue else super.newParameterValue(isInstanceMethod, local, tp) } - def newOperation(insn: AbstractInsnNode): NullnessValue = { - val nullness = (insn.getOpcode: @switch) match { - case Opcodes.ACONST_NULL => Null + def newOperation(insn: AbstractInsnNode): NullnessValue = (insn.getOpcode: @switch) match { + case Opcodes.ACONST_NULL => NullValue - case Opcodes.LDC => insn.asInstanceOf[LdcInsnNode].cst match { - case _: String | _: Type => NotNull - case _ => Unknown - } - - case _ => Unknown + case Opcodes.LDC => insn.asInstanceOf[LdcInsnNode].cst match { + case _: String | _: Type => NotNullValue + case _ => NullnessValue.unknown(insn) } // for Opcodes.NEW, we use Unknown. The value will become NotNull after the constructor call. - NullnessValue(nullness, insn) + case _ => NullnessValue.unknown(insn) } def copyOperation(insn: AbstractInsnNode, value: NullnessValue): NullnessValue = value @@ -182,26 +108,24 @@ final class NullnessInterpreter extends Interpreter[NullnessValue](Opcodes.ASM5) case Opcodes.CHECKCAST => value case Opcodes.NEWARRAY | - Opcodes.ANEWARRAY => NullnessValue(NotNull, isSize2 = false) + Opcodes.ANEWARRAY => NotNullValue - case _ => NullnessValue(Unknown, insn) + case _ => NullnessValue.unknown(insn) } def binaryOperation(insn: AbstractInsnNode, value1: NullnessValue, value2: NullnessValue): NullnessValue = { - NullnessValue(Unknown, insn) + NullnessValue.unknown(insn) } - def ternaryOperation(insn: AbstractInsnNode, value1: NullnessValue, value2: NullnessValue, value3: NullnessValue): NullnessValue = { - NullnessValue(Unknown, isSize2 = false) - } + def ternaryOperation(insn: AbstractInsnNode, value1: NullnessValue, value2: NullnessValue, value3: NullnessValue): NullnessValue = UnknownValue1 - def naryOperation(insn: AbstractInsnNode, values: util.List[_ <: NullnessValue]): NullnessValue = (insn.getOpcode: @switch) match { - case Opcodes.MULTIANEWARRAY => - NullnessValue(NotNull, isSize2 = false) + def naryOperation(insn: AbstractInsnNode, values: util.List[_ <: NullnessValue]): NullnessValue = insn match { + case mi: MethodInsnNode if bTypes.backendUtils.isNonNullMethodInvocation(mi) => + NotNullValue case _ => - // TODO: use a list of methods that are known to return non-null values - NullnessValue(Unknown, insn) + if (insn.getOpcode == Opcodes.MULTIANEWARRAY) NotNullValue + else NullnessValue.unknown(insn) } def returnOperation(insn: AbstractInsnNode, value: NullnessValue, expected: NullnessValue): Unit = () @@ -219,8 +143,10 @@ class NullnessFrame(nLocals: Int, nStack: Int) extends AliasingFrame[NullnessVal override def execute(insn: AbstractInsnNode, interpreter: Interpreter[NullnessValue]): Unit = { import Opcodes._ - // get the object id of the object that is known to be not-null after this operation - val nullCheckedAliasId: Long = (insn.getOpcode: @switch) match { + // get the alias set the object that is known to be not-null after this operation. + // alias sets are mutable / mutated, so after super.execute, this set contains the remaining + // aliases of the value that becomes not-null. + val nullCheckedAliases: AliasSet = (insn.getOpcode: @switch) match { case IALOAD | LALOAD | FALOAD | @@ -229,7 +155,7 @@ class NullnessFrame(nLocals: Int, nStack: Int) extends AliasingFrame[NullnessVal BALOAD | CALOAD | SALOAD => - aliasId(this.stackTop - 1) + aliasesOf(this.stackTop - 1) case IASTORE | FASTORE | @@ -239,35 +165,36 @@ class NullnessFrame(nLocals: Int, nStack: Int) extends AliasingFrame[NullnessVal SASTORE | LASTORE | DASTORE => - aliasId(this.stackTop - 2) + aliasesOf(this.stackTop - 2) case GETFIELD => - aliasId(this.stackTop) + aliasesOf(this.stackTop) case PUTFIELD => - aliasId(this.stackTop - 1) + aliasesOf(this.stackTop - 1) case INVOKEVIRTUAL | INVOKESPECIAL | INVOKEINTERFACE => val desc = insn.asInstanceOf[MethodInsnNode].desc val numArgs = Type.getArgumentTypes(desc).length - aliasId(this.stackTop - numArgs) + aliasesOf(this.stackTop - numArgs) case ARRAYLENGTH | MONITORENTER | MONITOREXIT => - aliasId(this.stackTop) + aliasesOf(this.stackTop) case _ => - -1 + null } super.execute(insn, interpreter) - if (nullCheckedAliasId != -1) { - for (i <- valuesWithAliasId(nullCheckedAliasId)) - this.setValue(i, NotNullValue) + if (nullCheckedAliases != null) { + val it = nullCheckedAliases.iterator + while (it.hasNext) + this.setValue(it.next(), NotNullValue) } } } @@ -276,7 +203,7 @@ class NullnessFrame(nLocals: Int, nStack: Int) extends AliasingFrame[NullnessVal * This class is required to override the `newFrame` methods, which makes makes sure the analyzer * uses NullnessFrames. */ -class NullnessAnalyzer extends Analyzer[NullnessValue](new NullnessInterpreter) { +class NullnessAnalyzer(bTypes: BTypes, method: MethodNode) extends Analyzer[NullnessValue](new NullnessInterpreter(bTypes, method)) { override def newFrame(nLocals: Int, nStack: Int): NullnessFrame = new NullnessFrame(nLocals, nStack) override def newFrame(src: Frame[_ <: NullnessValue]): NullnessFrame = new NullnessFrame(src) } diff --git a/src/compiler/scala/tools/nsc/backend/jvm/analysis/ProdConsAnalyzer.scala b/src/compiler/scala/tools/nsc/backend/jvm/analysis/ProdConsAnalyzerImpl.scala index 594fd8923c..8af4bd4d5d 100644 --- a/src/compiler/scala/tools/nsc/backend/jvm/analysis/ProdConsAnalyzer.scala +++ b/src/compiler/scala/tools/nsc/backend/jvm/analysis/ProdConsAnalyzerImpl.scala @@ -15,11 +15,10 @@ import scala.tools.asm.{Type, MethodVisitor} import scala.tools.asm.Opcodes._ import scala.tools.asm.tree._ import scala.tools.asm.tree.analysis._ -import scala.tools.nsc.backend.jvm.BTypes.InternalName import opt.BytecodeUtils._ -import scala.collection.convert.decorateAsScala._ +import scala.collection.JavaConverters._ /** * This class provides additional queries over ASM's built-in `SourceValue` analysis. @@ -55,24 +54,16 @@ import scala.collection.convert.decorateAsScala._ * * If ever needed, we could introduce a mode where primitive conversions (l2i) are considered as * copying operations. + * + * Note on performance: thee data flow analysis (SourceValue / SourceInterpreter, provided by ASM) + * is roughly 2-3x slower than a simple analysis (like BasicValue). The reason is that the merge + * function (merging producer sets) is more complex than merging simple basic values. + * See also the doc comment in the package object `analysis`. */ -class ProdConsAnalyzer(methodNode: MethodNode, classInternalName: InternalName) { - - /* Timers for benchmarking ProdCons - import scala.reflect.internal.util.Statistics._ - import ProdConsAnalyzer._ - val analyzerTimer = newSubTimer(classInternalName + "#" + methodNode.name + " - analysis", prodConsAnalyzerTimer) - val consumersTimer = newSubTimer(classInternalName + "#" + methodNode.name + " - consumers", prodConsAnalyzerTimer) - */ - - val analyzer = new Analyzer(new InitialProducerSourceInterpreter) +trait ProdConsAnalyzerImpl { + val methodNode: MethodNode -// val start = analyzerTimer.start() - analyzer.analyze(classInternalName, methodNode) -// analyzerTimer.stop(start) -// println(analyzerTimer.line) - - def frameAt(insn: AbstractInsnNode) = analyzer.frameAt(insn, methodNode) + def frameAt(insn: AbstractInsnNode): Frame[SourceValue] /** * Returns the potential producer instructions of a (local or stack) value in the frame of `insn`. @@ -102,8 +93,13 @@ class ProdConsAnalyzer(methodNode: MethodNode, classInternalName: InternalName) inputValues(insn).iterator.flatMap(v => v.insns.asScala).toSet } - def consumersOfOutputsFrom(insn: AbstractInsnNode): Set[AbstractInsnNode] = - _consumersOfOutputsFrom.get(insn).map(v => v.indices.flatMap(v.apply)(collection.breakOut): Set[AbstractInsnNode]).getOrElse(Set.empty) + def consumersOfOutputsFrom(insn: AbstractInsnNode): Set[AbstractInsnNode] = insn match { + case _: UninitializedLocalProducer => Set.empty + case ParameterProducer(local) => consumersOfValueAt(methodNode.instructions.getFirst, local) + case ExceptionProducer(handlerLabel, handlerFrame) => consumersOfValueAt(handlerLabel, handlerFrame.stackTop) + case _ => + _consumersOfOutputsFrom.get(insn).map(v => v.indices.flatMap(v.apply)(collection.breakOut): Set[AbstractInsnNode]).getOrElse(Set.empty) + } /** * Returns the potential initial producer instructions of a value in the frame of `insn`. @@ -159,13 +155,19 @@ class ProdConsAnalyzer(methodNode: MethodNode, classInternalName: InternalName) inputValueSlots(insn).flatMap(slot => initialProducersForValueAt(insn, slot)).toSet } - def ultimateConsumersOfOutputsFrom(insn: AbstractInsnNode): Set[AbstractInsnNode] = { - lazy val next = insn.getNext - outputValueSlots(insn).flatMap(slot => ultimateConsumersOfValueAt(next, slot)).toSet + def ultimateConsumersOfOutputsFrom(insn: AbstractInsnNode): Set[AbstractInsnNode] = insn match { + case _: UninitializedLocalProducer => Set.empty + case _ => + lazy val next = insn match { + case _: ParameterProducer => methodNode.instructions.getFirst + case ExceptionProducer(handlerLabel, _) => handlerLabel + case _ => insn.getNext + } + outputValueSlots(insn).flatMap(slot => ultimateConsumersOfValueAt(next, slot)).toSet } private def isCopyOperation(insn: AbstractInsnNode): Boolean = { - isVarInstruction(insn) || { + isLoadOrStore(insn) || { (insn.getOpcode: @switch) match { case DUP | DUP_X1 | DUP_X2 | DUP2 | DUP2_X1 | DUP2_X2 | SWAP | CHECKCAST => true case _ => false @@ -376,9 +378,9 @@ class ProdConsAnalyzer(methodNode: MethodNode, classInternalName: InternalName) Seq(insn.asInstanceOf[IincInsnNode].`var`) } else { val frame = frameAt(insn) - val stackEffect = InstructionStackEffect(insn, frame) + val prodCons = InstructionStackEffect.forAsmAnalysis(insn, frame) val stackSize = frame.getLocals + frame.getStackSize - (stackSize - stackEffect._1) until stackSize + (stackSize - InstructionStackEffect.cons(prodCons)) until stackSize } } @@ -386,7 +388,7 @@ class ProdConsAnalyzer(methodNode: MethodNode, classInternalName: InternalName) private def outputValueSlots(insn: AbstractInsnNode): Seq[Int] = insn match { case ParameterProducer(local) => Seq(local) case UninitializedLocalProducer(local) => Seq(local) - case ExceptionProducer(frame) => Seq(frame.stackTop) + case ExceptionProducer(_, frame) => Seq(frame.stackTop) case _ => if (insn.getOpcode == -1) return Seq.empty if (isStore(insn)) { @@ -395,16 +397,15 @@ class ProdConsAnalyzer(methodNode: MethodNode, classInternalName: InternalName) Seq(insn.asInstanceOf[IincInsnNode].`var`) } else { val frame = frameAt(insn) - val stackEffect = InstructionStackEffect(insn, frame) + val prodCons = InstructionStackEffect.forAsmAnalysis(insn, frame) val nextFrame = frameAt(insn.getNext) val stackSize = nextFrame.getLocals + nextFrame.getStackSize - (stackSize - stackEffect._2) until stackSize + (stackSize - InstructionStackEffect.prod(prodCons)) until stackSize } } /** For each instruction, a set of potential consumers of the produced values. */ private lazy val _consumersOfOutputsFrom: Map[AbstractInsnNode, Vector[Set[AbstractInsnNode]]] = { -// val start = consumersTimer.start() var res = Map.empty[AbstractInsnNode, Vector[Set[AbstractInsnNode]]] for { insn <- methodNode.instructions.iterator.asScala @@ -417,8 +418,6 @@ class ProdConsAnalyzer(methodNode: MethodNode, classInternalName: InternalName) val outputIndex = producedSlots.indexOf(i) res = res.updated(producer, currentConsumers.updated(outputIndex, currentConsumers(outputIndex) + insn)) } -// consumersTimer.stop(start) -// println(consumersTimer.line) res } @@ -426,11 +425,6 @@ class ProdConsAnalyzer(methodNode: MethodNode, classInternalName: InternalName) private val _ultimateConsumersCache: mutable.AnyRefMap[(AbstractInsnNode, Int), Set[AbstractInsnNode]] = mutable.AnyRefMap.empty } -object ProdConsAnalyzer { - import scala.reflect.internal.util.Statistics._ - val prodConsAnalyzerTimer = newTimer("Time in ProdConsAnalyzer", "jvm") -} - /** * A class for pseudo-instructions representing the initial producers of local values that have * no producer instruction in the method: @@ -446,10 +440,10 @@ object ProdConsAnalyzer { * return a; * } * - * In the first frame of the method, the SoruceValue for parameter `a` gives an empty set of + * In the first frame of the method, the SourceValue for parameter `a` gives an empty set of * producer instructions. * - * In the frame of the `IRETURN` instruction, the SoruceValue for parameter `a` lists a single + * In the frame of the `IRETURN` instruction, the SourceValue for parameter `a` lists a single * producer instruction: the `ISTORE 1`. This makes it look as if there was a single producer for * `a`, where in fact it might still hold the parameter's initial value. */ @@ -459,9 +453,9 @@ abstract class InitialProducer extends AbstractInsnNode(-1) { override def accept(cv: MethodVisitor): Unit = throw new UnsupportedOperationException } -case class ParameterProducer(local: Int) extends InitialProducer -case class UninitializedLocalProducer(local: Int) extends InitialProducer -case class ExceptionProducer(handlerFrame: Frame[_ <: Value]) extends InitialProducer +case class ParameterProducer(local: Int) extends InitialProducer +case class UninitializedLocalProducer(local: Int) extends InitialProducer +case class ExceptionProducer[V <: Value](handlerLabel: LabelNode, handlerFrame: Frame[V]) extends InitialProducer class InitialProducerSourceInterpreter extends SourceInterpreter { override def newParameterValue(isInstanceMethod: Boolean, local: Int, tp: Type): SourceValue = { @@ -473,6 +467,6 @@ class InitialProducerSourceInterpreter extends SourceInterpreter { } override def newExceptionValue(tryCatchBlockNode: TryCatchBlockNode, handlerFrame: Frame[_ <: Value], exceptionType: Type): SourceValue = { - new SourceValue(1, ExceptionProducer(handlerFrame)) + new SourceValue(1, ExceptionProducer(tryCatchBlockNode.handler, handlerFrame)) } } diff --git a/src/compiler/scala/tools/nsc/backend/jvm/analysis/TypeFlowInterpreter.scala b/src/compiler/scala/tools/nsc/backend/jvm/analysis/TypeFlowInterpreter.scala new file mode 100644 index 0000000000..bcf9978c16 --- /dev/null +++ b/src/compiler/scala/tools/nsc/backend/jvm/analysis/TypeFlowInterpreter.scala @@ -0,0 +1,36 @@ +package scala.tools.nsc +package backend.jvm +package analysis + +import scala.tools.asm.Type +import scala.tools.asm.tree.analysis.{BasicValue, BasicInterpreter} + +abstract class TypeFlowInterpreter extends BasicInterpreter { + override def newValue(tp: Type) = { + if (tp == null) super.newValue(tp) + else if (isRef(tp)) new BasicValue(tp) + else super.newValue(tp) + } + + def isRef(tp: Type) = tp != null && (tp.getSort match { + case Type.OBJECT | Type.ARRAY => true + case _ => false + }) + + def refLub(a: BasicValue, b: BasicValue): BasicValue + + override def merge(a: BasicValue, b: BasicValue): BasicValue = { + if (a == b) a + else if (isRef(a.getType) && isRef(b.getType)) refLub(a, b) + else BasicValue.UNINITIALIZED_VALUE + } +} + +/** + * A [[TypeFlowInterpreter]] which collapses LUBs of non-equal reference types to Object. + * This could be made more precise by looking up ClassBTypes for the two reference types and using + * the `jvmWiseLUB` method. + */ +class NonLubbingTypeFlowInterpreter extends TypeFlowInterpreter { + def refLub(a: BasicValue, b: BasicValue): BasicValue = BasicValue.REFERENCE_VALUE // java/lang/Object +} diff --git a/src/compiler/scala/tools/nsc/backend/jvm/analysis/package.scala b/src/compiler/scala/tools/nsc/backend/jvm/analysis/package.scala new file mode 100644 index 0000000000..999c686aac --- /dev/null +++ b/src/compiler/scala/tools/nsc/backend/jvm/analysis/package.scala @@ -0,0 +1,374 @@ +package scala.tools.nsc.backend.jvm + +/** + * Summary on the ASM analyzer framework + * -------------------------------------- + * + * Value + * - Abstract, needs to be implemented for each analysis. + * - Represents the desired information about local variables and stack values, for example: + * - Is this value known to be null / not null? + * - What are the instructions that could potentially have produced this value? + * + * Interpreter + * - Abstract, needs to be implemented for each analysis. Sometimes one can subclass an existing + * interpreter, e.g., SourceInterpreter or BasicInterpreter. + * - Multiple abstract methods that receive an instruction and the instruction's input values, and + * return a value representing the result of that instruction. + * - Note: due to control flow, the interpreter can be invoked multiple times for the same + * instruction, until reaching a fixed point. + * - Abstract `merge` function that computes the least upper bound of two values. Used by + * Frame.merge (see below). + * + * Frame + * - Can be used directly for many analyses, no subclass required. + * - Every frame has an array of values: one for each local variable and for each stack slot. + * - A `top` index stores the index of the current stack top + * - NOTE: for a size-2 local variable at index i, the local variable at i+1 is set to an empty + * value. However, for a size-2 value at index i on the stack, the value at i+1 holds the next + * stack value. IMPORTANT: this is only the case in ASM's analysis framework, not in bytecode. + * See comment below. + * - Defines the `execute(instruction)` method. + * - executing mutates the state of the frame according to the effect of the instruction + * - pop consumed values from the stack + * - pass them to the interpreter together with the instruction + * - if applicable, push the resulting value on the stack + * - Defines the `merge(otherFrame)` method + * - called by the analyzer when multiple control flow paths lead to an instruction + * - the frame at the branching instruction is merged into the current frame of the + * instruction (held by the analyzer) + * - mutates the values of the current frame, merges all values using interpreter.merge. + * + * Analyzer + * - Stores a frame for each instruction + * - `merge` function takes an instruction and a frame, merges the existing frame for that instr + * (from the frames array) with the new frame passed as argument. + * if the frame changed, puts the instruction on the work queue (fixpoint). + * - initial frame: initialized for first instr by calling interpreter.new[...]Value + * for each slot (locals and params), stored in frames[firstInstr] by calling `merge` + * - work queue of instructions (`queue` array, `top` index for next instruction to analyze) + * - analyze(method): simulate control flow. while work queue non-empty: + * - copy the state of `frames[instr]` into a local frame `current` + * - call `current.execute(instr, interpreter)`, mutating the `current` frame + * - if it's a branching instruction + * - for all potential destination instructions + * - merge the destination instruction frame with the `current` frame + * (this enqueues the destination instr if its frame changed) + * - invoke `newControlFlowEdge` (see below) + * - the analyzer also tracks active exception handlers at each instruction + * - the empty method `newControlFlowEdge` can be overridden to track control flow if required + * + * + * MaxLocals and MaxStack + * ---------------------- + * + * At the JVM level, long and double values occupy two slots, both as local variables and on the + * stack, as specified in the JVM spec 2.6.2: + * "At any point in time, an operand stack has an associated depth, where a value of type long or + * double contributes two units to the depth and a value of any other type contributes one unit." + * + * For example, a method + * class A { def f(a: Long, b: Long) = a + b } + * has MAXSTACK=4 in the classfile. This value is computed by the ClassWriter / MethodWriter when + * generating the classfile (we always pass COMPUTE_MAXS to the ClassWriter). + * + * For running an ASM Analyzer, long and double values occupy two local variable slots, but only + * a single slot on the call stack, as shown by the following snippet: + * + * import scala.tools.nsc.backend.jvm._ + * import scala.tools.nsc.backend.jvm.opt.BytecodeUtils._ + * import scala.collection.convert.decorateAsScala._ + * import scala.tools.asm.tree.analysis._ + * + * val cn = AsmUtils.readClass("/Users/luc/scala/scala/sandbox/A.class") + * val m = cn.methods.iterator.asScala.find(_.name == "f").head + * + * // the value is read from the classfile, so it's 4 + * println(s"maxLocals: ${m.maxLocals}, maxStack: ${m.maxStack}") // maxLocals: 5, maxStack: 4 + * + * // we can safely set it to 2 for running the analyzer. + * m.maxStack = 2 + * + * val a = new Analyzer(new BasicInterpreter) + * a.analyze(cn.name, m) + * val addInsn = m.instructions.iterator.asScala.find(_.getOpcode == 97).get // LADD Opcode + * val addFrame = a.frameAt(addInsn, m) + * + * addFrame.getStackSize // 2: the two long values only take one slot each + * addFrame.getLocals // 5: this takes one slot, the two long parameters take 2 slots each + * + * + * While running the optimizer, we need to make sure that the `maxStack` value of a method is + * large enough for running an ASM analyzer. We don't need to worry if the value is incorrect in + * the JVM perspective: the value will be re-computed and overwritten in the ClassWriter. + * + * + * Lessons learnt while benchmarking the alias tracking analysis + * ------------------------------------------------------------- + * + * Profiling + * - Use YourKit for finding hotspots (cpu profiling). when it comes to drilling down into the details + * of a hotspot, don't pay too much attention to the percentages / time counts. + * - Should also try other profilers. + * - Use timers. When a method showed up as a hotspot, I added a timer around that method, and a + * second one within the method to measure specific parts. The timers slow things down, but the + * relative numbers show what parts of a method are slow. + * + * ASM analyzer insights + * - The time for running an analysis depends on the number of locals and the number of instructions. + * Reducing the number of locals helps speeding up the analysis: there are less values to + * merge when merging to frames. + * See also https://github.com/scala/scala-dev/issues/47 + * - The common hot spot of an ASM analysis is Frame.merge, for example in producers / consumers. + * - For nullness analysis the time is spent as follows + * - 20% merging nullness values. this is as expected: for example, the same absolute amount of + * time is spent in merging BasicValues when running a BasicInterpreter. + * - 50% merging alias sets. i tried to optimize what i could out of this. + * - 20% is spent creating new frames from existing ones, see comment on AliasingFrame.init. + * - The implementation of Frame.merge (the main hot spot) contains a megamorphic callsite to + * `interpreter.merge`. This can be observed easily by running a test program that either runs + * a BasicValue analysis only, versus a program that first runs a nullness analysis and then + * a BasicValue. In an example, the time for the BasicValue analysis goes from 519ms to 1963ms, + * a 3.8x slowdown. + * - I added counters to the Frame.merge methods for nullness and BasicValue analysis. In the + * examples I benchmarked, the number of merge invocations was always exactly the same. + * It would probably be possible to come up with an example where alias set merging forces + * additional analysis rounds until reaching the fixpoint, but I did not observe such cases. + * + * To benchmark an analysis, instead of benchmarking analysis while it runs in the compiler + * backend, one can easily run it from a separate program (or the repl). The bytecode to analyze + * can simply be parsed from a classfile. See example at the end of this comment. + * + * + * Nullness Analysis in Miguel's Optimizer + * --------------------------------------- + * + * Miguel implemented alias tracking for nullness analysis differently [1]. Remember that every + * frame has an array of values. Miguel's idea was to represent aliasing using reference equality + * in the values array: if two entries in the array point to the same value object, the two entries + * are aliases in the frame of the given instruction. + * + * While this idea seems elegant at first sight, Miguel's implementation does not merge frames + * correctly when it comes to aliasing. Assume in frame 1, values (a, b, c) are aliases, while in + * frame 2 (a, b) are aliases. When merging the second into the first, we have to make sure that + * c is removed as an alias of (a, b). + * + * It would be possible to implement correct alias set merging in Miguel's approach. However, frame + * merging is the main hot spot of analysis. The computational complexity of implementing alias set + * merging by traversing the values array and comparing references is too high. The concrete + * alias set representation that is used in the current implementation (see class AliasingFrame) + * makes alias set merging more efficient. + * + * [1] https://github.com/scala-opt/scala/blob/opt/rebase/src/compiler/scala/tools/nsc/backend/bcode/NullnessPropagator.java + * + * + * Complexity and scaling of analysis + * ---------------------------------- + * + * The time complexity of a data flow analysis depends on: + * + * - The size of the method. The complexity factor is linear (assuming the number of locals and + * branching instructions remains constant). The main analysis loop runs through all + * instructions of a method once. Instructions are only re-enqueued if a control flow merge + * changes the frame at some instruction. + * + * - The branching instructions. When a second (third, ..) control flow edge arrives at an + * instruction, the existing frame at the instruction is merged with the one computed on the + * new branch. If the merge function changes the existing frame, the instruction is enqueued + * for another analysis. This results in a merge operation for the successors of the + * instruction. + * + * - The number of local variables. The hot spot of analysis is frame merging. The merge function + * iterates through the values in the frame (locals and stack values) and merges them. + * + * I measured the running time of an analysis for two examples: + * - Keep the number of locals and branching instructions constant, increase the number of + * instructions. The running time grows linearly with the method size. + * - Increase the size and number of locals in a method. The method size and number of locals + * grow in the same pace. Here, the running time increase is polynomial. It looks like the + * complexity is be #instructions * #locals^2 (see below). + * + * I measured nullness analysis (which tracks aliases) and a SimpleValue analysis. Nullness runs + * roughly 5x slower (because of alias tracking) at every problem size - this factor doesn't change. + * + * The numbers below are for nullness. Note that the last column is constant, i.e., the running + * time is proportional to #ins * #loc^2. Therefore we use this factor when limiting the maximal + * method size for running an analysis. + * + * #insns #locals time (ms) time / #ins * #loc^2 * 10^6 + * 1305 156 34 1.07 + * 2610 311 165 0.65 + * 3915 466 490 0.57 + * 5220 621 1200 0.59 + * 6525 776 2220 0.56 + * 7830 931 3830 0.56 + * 9135 1086 6570 0.60 + * 10440 1241 9700 0.60 + * 11745 1396 13800 0.60 + * + * As a second experiment, nullness analysis was run with varying #insns but constant #locals. + * The last column shows linear complexity with respect to the method size (linearOffset = 2279): + * + * #insns #locals time (ms) (time + linearOffset) / #insns + * 5220 621 1090 0.645 + * 6224 621 1690 0.637 + * 7226 621 2280 0.630 + * 8228 621 2870 0.625 + * 9230 621 3530 0.629 + * 10232 621 4130 0.626 + * 11234 621 4770 0.627 + * 12236 621 5520 0.637 + * 13238 621 6170 0.638 + * + * + * When running a BasicValue analysis, the complexity observation is the same (time is proportional + * to #ins * #loc^2). + * + * + * Measuring analysis execution time + * --------------------------------- + * + * See code below. + */ + +/* +object Test { + val overwrite: Option[String] = null + + @noinline def serialize(o: AnyRef): String = null + + @noinline def deserialize(string: String): AnyRef = null + + @inline def checkRoundTrip[T <: AnyRef](instance: T)(f: T => AnyRef) { + val result = serialize(instance) + val reconstituted = deserialize(result).asInstanceOf[T] + assert(f(instance) == f(reconstituted), (f(instance), f(reconstituted))) + } + + @inline def check[T <: AnyRef](instance: => T)(prevResult: String, f: T => AnyRef = (x: T) => x) { + // pattern match to introduce a lot of control flow, i.e., a lot of frame merges + overwrite match { + case Some(f) => + case None => + checkRoundTrip(instance)(f) + assert(f(deserialize(prevResult).asInstanceOf[T]) == f(instance), instance) + assert(prevResult == "res", instance) + } + } + + // @inline def fun[T <: AnyRef](instance: => T) = (x: T) => x + + def testMain(): Unit = { + // every call to check creates quite a number of locals, and also quite a number of aliases + // of the same value (x1). First of all, the default argument call is expanded as below. Then + // method check is inlined, and within the body of check, checkRoundTrip and assert have + // already been inlined as well. + + // { + // val x1 = () => "" + // val x2 = fun(x1()) // the compiler optimizes this: instead of passing `() => x1()`, it just passes x1 + // check(x1())("", x2) // same here for x1 + // } + + check("")("") + check("")("") + check("")("") + check("")("") + check("")("") // 5 + check("")("") + check("")("") + check("")("") + check("")("") + check("")("") // 10 + check("")("") + check("")("") + check("")("") + check("")("") + check("")("") // 15 + check("")("") + check("")("") + check("")("") + check("")("") + check("")("") // 20 + check("")("") + check("")("") + check("")("") + check("")("") + check("")("") // 25 + check("")("") + check("")("") + check("")("") + check("")("") + check("")("") // 30 + check("")("") + check("")("") + check("")("") + check("")("") + check("")("") // 35 + check("")("") + check("")("") + check("")("") + check("")("") + check("")("") // 40 + // check("")("") + // check("")("") + // check("")("") + // check("")("") + // check("")("") // 45 + // check("")("") + // check("")("") + // check("")("") + // check("")("") + // check("")("") // 50 + // check("")("") + // check("")("") + // check("")("") + // check("")("") + // check("")("") // 55 + + // 1000 bytecode instructions, 0 locals + // println((1,2,3,4,5,6,7,8,9,10)); println((1,2,3,4,5,6,7,8,9,10)); println((1,2,3,4,5,6,7,8,9,10)); println((1,2,3,4,5,6,7,8,9,10)); println((1,2,3,4,5,6,7,8,9,10)); println((1,2,3,4,5,6,7,8,9,10)); println((1,2,3,4,5,6,7,8,9,10)); println((1,2,3,4,5,6,7,8,9,10)); println((1,2,3,4,5,6,7,8,9,10)); println((1,2,3,4,5,6,7,8,9,10)); println((1,2,3,4,5,6,7,8,9,10)); println((1,2,3,4,5,6,7,8,9,10)); println((1,2,3,4,5,6,7,8,9,10)); println((1,2,3,4,5,6,7,8,9,10)); println((1,2,3,4,5,6,7,8,9,10)); println((1,2,3,4,5,6,7,8,9,10)); println((1,2,3,4,5,6,7,8,9,10)); println((1,2,3,4,5,6,7,8,9,10)); println((1,2,3,4,5,6,7,8,9,10)); println((1,2,3,4,5,6,7,8,9,10)); println((1,2,3,4,5,6,7,8,9,10)); println((1,2,3,4,5,6,7,8,9,10)); println((1,2,3,4,5,6,7,8,9,10)); println((1,2,3,4,5,6,7,8,9,10)); println((1,2,3,4,5,6,7,8,9,10)); println((1,2,3,4,5,6,7,8,9,10)); println((1,2,3,4,5,6,7,8,9,10)); println((1,2,3,4,5,6,7,8,9,10)); println((1,2,3,4,5,6,7,8,9,10)); println((1,2,3,4,5,6,7,8,9,10)); println((1,2,3,4,5,6,7,8,9,10)); println((1,2,3,4,5,6,7,8,9,10)); println((1,2,3,4,5,6,7,8,9,10)); println((1,2,3,4,5,6,7,8,9,10)); println((1,2,3,4,5,6,7,8,9,10)); println((1,2,3,4,5,6,7,8,9,10)); println((1,2,3,4,5,6,7,8,9,10)); println((1,2,3,4,5,6,7,8,9,10)); println((1,2,3,4,5,6,7,8,9,10)); println((1,2,3,4,5,6,7,8,9,10)); + } + + def timed[T](f: => T): T = { + val start = System.nanoTime() + val r = f + val nanos = System.nanoTime() - start + println(s"took ${nanos/1000000}ms") + r + } + + def main(args: Array[String]): Unit = { + import scala.tools.nsc.backend.jvm._ + val cn = AsmUtils.readClass("/Users/luc/scala/scala/sandbox/Test$.class") + import scala.collection.convert.decorateAsScala._ + val m = cn.methods.iterator.asScala.find(_.name == "testMain").head + + println(s"${m.instructions.size} instructions - ${m.maxLocals} locals") + + val a = new analysis.NullnessAnalyzer + a.analyze(cn.name, m) // warm up + + analysis.AliasingFrame.reset() + timed(a.analyze(cn.name, m)) + analysis.AliasingFrame.timers foreach println + + println("---") + + // NOTE: if we don't run nullness analysis above (comment it out), then the BasicValue + // analysis runs 3.5x faster. Most likely because the call to Interpreter.merge inside + // Frame.merge is no longer megamorphic. + + import scala.tools.asm.tree.analysis._ + val ba = new Analyzer(new BasicInterpreter) + ba.analyze(cn.name, m) // warm up + + timed(ba.analyze(cn.name, m)) + + println("---") + + timed(a.analyze(cn.name, m)) + } +} +*/ +package object analysis diff --git a/src/compiler/scala/tools/nsc/backend/jvm/opt/BoxUnbox.scala b/src/compiler/scala/tools/nsc/backend/jvm/opt/BoxUnbox.scala new file mode 100644 index 0000000000..78fc7e1ecf --- /dev/null +++ b/src/compiler/scala/tools/nsc/backend/jvm/opt/BoxUnbox.scala @@ -0,0 +1,907 @@ +/* NSC -- new Scala compiler + * Copyright 2005-2014 LAMP/EPFL + * @author Martin Odersky + */ + +package scala.tools.nsc +package backend.jvm +package opt + +import scala.annotation.tailrec +import scala.tools.asm.Type +import scala.tools.asm.Opcodes._ +import scala.tools.asm.tree._ +import scala.collection.mutable +import scala.collection.JavaConverters._ +import scala.tools.nsc.backend.jvm.BTypes.InternalName +import scala.tools.nsc.backend.jvm.opt.BytecodeUtils._ + +class BoxUnbox[BT <: BTypes](val btypes: BT) { + import btypes._ + import backendUtils._ + + /** + * Eliminate box-unbox pairs within `method`. Such appear commonly after closure elimination: + * + * def t2 = { + * val f = (b: Byte, i: Int) => i + b // no specialized variant for this function type + * f(1, 2) // invokes the generic `apply` + * } + * + * The closure optimizer re-writes the `apply` call to `anonfun$adapted` method, which takes + * boxed arguments. After inlining this method, we get + * + * def t2 = { + * val a = boxByte(1) + * val b = boxInteger(2) + * val r = boxInteger(anonfun$(unboxByte(a), unboxInt(b))) + * unboxInt(r) + * } + * + * All these box/unbox operations are eliminated here. + * + * Implementation: for every box operation, find all consumers of the boxed value, then all + * producers of these consumers, repeat until reaching a fixpoint. If this results in a set of + * boxing and unboxing operations, the box can be eliminated. + * + * There are two methods for eliminating boxes: + * M1: If there is a single boxing operation, the boxed value(s) are stored into new local + * variable(s) at the allocation site. Accesses to the boxed value are re-written to reads / + * writes of these locals. Advantages: + * - supports mutable boxes (IntRef and friends) + * - supports eliminating unbox operations even if the box object needs to be created + * because it escapes (see E4) + * - works by keeping the unboxed value(s) in locals AND the box in its original form + * - only for immutable boxes: modifications to the escaped box cannot be applied to + * the local variable(s) holding the boxed value(s). + * Restriction: + * - does not work if there are multiple boxing operations (see E1) + * + * M2: If there are multiple boxing operations, the boxing operations are simply eliminated, + * leaving the unboxed value(s) on the stack. Store / load operations that previously + * acted on the box are adapted to handle the boxed type(s). If the box contains multiple + * values (or a size-2 value, which doesn't fit into locals that were used for the box), + * new local slots are used for store / load operations. Restrictions: + * - does not support re-writing writes to (mutable) boxes (see E2) + * - does not support re-writing reads of boxes that also escape (see E3) + * + * + * E1: M1 only works if there's a single boxing operation. + * def e1(b: Boolean) = { + * val i: Integer = box(10) // 10 is stored into a new local, box operation and i removed + * val j: Integer = box(20) // 20 is stored into a new local, box operation and j removed + * val r = if (b) i else j // loads and stores of the box are eliminated, r no longer exists + * unbox(r) // cannot rewrite: we don't know which local to load + * } + * Note: the example has no write and the box does not escape, so M2 works here. + * + * E2: mutable boxes with multiple boxing operations cannot be eliminated. + * M1: see E1 + * M2: cannot replace an `IntRef` on the stack by an `Int` value on the stack, an Int on the + * stack cannot be modified. + * + * def e2(b: Boolean) = { + * val r1 = new IntRef(0) + * val r2 = new IntRef(1) + * val modRef = if (b) r1 else r2 + * modRef.elem += 10 // M1: cannot rewrite: which local to write? same as E1. + * (if (b) r1 else r2).elem += 10 // M2: cannot change an Int on the stack + * (r1.elem, r2.elem) + * } + * + * + * E3: escaping boxes with multiple boxing operations cannot be rewritten. + * M1: see E1. + * M2: at *, instead of an Integer, an Int is on the stack, but the escape method expects an + * Integer. We cannot just create a box at this point: if there are multiple escapes (or + * an escape is executed more than once), the difference could be observed (reference + * equality). + * + * def e3(b: Boolean) = { + * val i: Integer = box(1) + * val j: Integer = box(2) + * escape(if (b) i else j) // * + * unbox(if (b) i else j) + * } + * + * + * E4: M1 supports rewriting unbox operations of immutable boxes that escape + * def e4 = { + * val i: Integer = box(10) // 10 is stored into a new local, loaded as argument for the box call + * escape(i) // not changed, still loads the local i holding the box + * unbox(i) // rewritten to a pop (of the box) and a load of the local variable + * } + * + * + * E4 seems to be a bit of a corner case, but it's necessary to unblock box eliminations with + * mutual dependencies. Example: + * + * val ((a, b), c) = ((1, 2), 3) + * a + b + c + * + * generates (after a few cleanups) the following (pseudo-bytecode, ignoring primitive boxing, specialization): + * + * load 1, load 2, new Tuple2 // stack: Tuple2 + * load 3 // stack: Tuple2; Int + * val local1 = new Tuple2 + * val local2 = local1._1.asInstanceOf[Tuple2] + * val c = local1._2.asInstanceOf[Int] + * if (local2 == null) throw new MatchError(local1) + * val a = local2._1 + * val b = local2._2 + * a + b + c + * + * In order to eliminate the tuples, we first need to eliminate the outer tuple (stored in local1) + * - single box operation, so we use M1 + * - there are three consumers of the outer tuple: `local1._1`, `local1._2` and + * `new MatchError(local1)`. in the last one, the tuple escapes. + * - note that the MatchError creation is dead code: local2 is never null. However, our nullness + * analysis cannot identify this: it does not track nullness through tuple stores and loads. + * - if we re-write the non-escaping consumers of the outer tuple, but keep the tuple allocation + * and the escaping consumer, we get the following: + * + * load 1, load 2 + * val newLocal1 = new Tuple2; load newLocal1 // stack: Tuple2 + * val newLocal2 = 3; load newLocal2 // stack: Tuple2; Int + * val local1 = new Tuple2 + * val local2 = newLocal1 + * val c = newLocal2 + * if (local2 == null) throw new MatchError(local1) + * val a = local2._1 + * val b = local2._2 + * a + b + c + * + * At this point, the nullness analysis sees that `local2 == null` is false, dead code elimination + * removes the `throw new MatchError(local1)`. After eliminating the allocation of the outer tuple, + * the inner tuple (stored in newLocal1) can also be eliminated. + * + * + * Special case for tuples wrt specialization: a tuple getter may box or unbox the value stored + * in the tuple: calling `_1` on a `Tuple2$mcII$sp` boxes the primitive Int stored in the tuple. + * Similarly, calling `_1$mcI$sp` on a non-specialized `Tuple2` unboxes the Integer in the tuple. + * When eliminating such getters, we have to introduce appropriate box / unbox calls. + * + * + * TODO: add new calls (box / unbox) to the call graph (not urgent) + * TODO: update the call graph because stack heights change (not urgent). + * this may also affect other optimizations, we ignored the issue so far. check how stack + * heights stored in the call graph are used. + * Note: these tasks are not urgent because the call graph is not currently used during / after + * method-local optimizations, only before to perform inlining and closure rewriting. + */ + def boxUnboxElimination(method: MethodNode, owner: InternalName): Boolean = { + AsmAnalyzer.sizeOKForSourceValue(method) && { + val toInsertBefore = mutable.Map.empty[AbstractInsnNode, List[AbstractInsnNode]] + val toReplace = mutable.Map.empty[AbstractInsnNode, List[AbstractInsnNode]] + val toDelete = mutable.Set.empty[AbstractInsnNode] + + val knownHandled = mutable.Set.empty[AbstractInsnNode] + + lazy val prodCons = new ProdConsAnalyzer(method, owner) + + var nextLocal = method.maxLocals + def getLocal(size: Int) = { + val r = nextLocal + nextLocal += size + r + } + + var maxStackGrowth = 0 + + /** Method M1 for eliminating box-unbox pairs (see doc comment in the beginning of this file) */ + def replaceBoxOperationsSingleCreation(creation: BoxCreation, finalCons: Set[BoxConsumer], boxKind: BoxKind, keepBox: Boolean): Unit = { + /** + * If the box is eliminated, all copy operations (loads, stores, others) of the box need to + * be removed. This method returns all copy operations that should be removed. + * + * Returns `None` in case some exotic copy operation is found that cannot be removed + * (DUP2_X1 and friends - these are never emitted by scalac). In this case, the box cannot + * be eliminated. + */ + def copyOpsToEliminate: Option[Set[AbstractInsnNode]] = { + var elidableCopyOps = Set.empty[AbstractInsnNode] + var replaceOK = true + val copyOps = new CopyOpsIterator(Set(creation), finalCons, prodCons) + while (replaceOK && copyOps.hasNext) copyOps.next() match { + case vi: VarInsnNode => + elidableCopyOps += vi + + case copyOp if copyOp.getOpcode == DUP => + elidableCopyOps += copyOp + + case _ => + replaceOK = false + } + if (replaceOK) Some(elidableCopyOps) else None + } + + val canRewrite = keepBox || (copyOpsToEliminate match { + case Some(copyOps) => + toDelete ++= copyOps + true + + case _ => false + }) + + if (canRewrite) { + val localSlots: Vector[(Int, Type)] = boxKind.boxedTypes.map(tp => (getLocal(tp.getSize), tp))(collection.breakOut) + + // store boxed value(s) into localSlots + val storeOps = localSlots.toList reverseMap { case (slot, tp) => + new VarInsnNode(tp.getOpcode(ISTORE), slot) + } + val storeInitialValues = creation.loadInitialValues match { + case Some(ops) => ops ::: storeOps + case None => storeOps + } + if (keepBox) { + val loadOps: List[VarInsnNode] = localSlots.map({ case (slot, tp) => + new VarInsnNode(tp.getOpcode(ILOAD), slot) + })(collection.breakOut) + toInsertBefore(creation.valuesConsumer) = storeInitialValues ::: loadOps + } else { + toReplace(creation.valuesConsumer) = storeInitialValues + toDelete ++= creation.allInsns - creation.valuesConsumer + } + + // rewrite consumers + finalCons foreach { + case write: StaticSetterOrInstanceWrite => + assert(!keepBox, s"cannot eliminate box write if the box remains (and escapes): $write") + val (slot, tp) = localSlots(boxKind.extractedValueIndex(write)) + val storeOp = new VarInsnNode(tp.getOpcode(ISTORE), slot) + toReplace(write.consumer) = List(storeOp) + + case c: EscapingConsumer => + assert(keepBox, s"found escaping consumer, but box is eliminated: $c") + + case extraction => + val (slot, tp) = localSlots(boxKind.extractedValueIndex(extraction)) + val loadOps = new VarInsnNode(tp.getOpcode(ILOAD), slot) :: extraction.postExtractionAdaptationOps(tp) + if (keepBox) toReplace(extraction.consumer) = getPop(1) :: loadOps + else toReplace(extraction.consumer) = loadOps + toDelete ++= extraction.allInsns - extraction.consumer + } + } + } + + /** Method M2 for eliminating box-unbox pairs (see doc comment in the beginning of this file) */ + def replaceBoxOperationsMultipleCreations(allCreations: Set[BoxCreation], allConsumers: Set[BoxConsumer], boxKind: BoxKind): Unit = { + /** + * If a single-value size-1 box is eliminated, local variables slots holding the box are + * reused to hold the unboxed value. In case there's an entry for that local variable in the + * method's local variables table (debug info), adapt the type. + * + * If there are multiple entries for a local variable that's changing types, then all + * entries for that variable are deleted - it's not obvious how to find the correct entry. + * Note that scalac never re-uses local variable slots for non-overlapping locals. Also note + * that all locals that are newly created during the optimizer don't have an entry either. + * + * Finally, note that variables that become unused are removed later from the table by + * removeUnusedLocalVariableNodes in LocalOpt. + * + * Unlike modifications that affect the method's instructions (which uses toReplace etc), + * we can directly modify the local variable table - it does not affect the frames of the + * ProdCons analysis. + */ + def updateLocalVariableTypes(reTypedLocals: Map[Int, Type]): Unit = { + lazy val localsByIndex = method.localVariables.asScala.groupBy(_.index) + for ((index, tp) <- reTypedLocals) localsByIndex.get(index).map(_.toList) match { + case Some(List(local)) => + local.desc = tp.getDescriptor + case Some(locals) => + locals foreach method.localVariables.remove + case _ => + } + } + + /** Remove box creations - leave the boxed value(s) on the stack instead. */ + def replaceCreationOps(): Unit = { + for (creation <- allCreations) creation.loadInitialValues match { + case None => + toDelete ++= creation.allInsns + + case Some(ops) => + toReplace(creation.valuesConsumer) = ops + toDelete ++= (creation.allInsns - creation.valuesConsumer) + } + } + + /** + * Replace a value extraction operation. For a single-value box, the extraction operation can + * just be removed. An extraction from a multi-value box is replaced by POP operations for the + * non-used values, and an xSTORE / xLOAD for the extracted value. Example: tuple3._2 becomes + * POP; xSTORE n; POP; xLOAD n. + */ + def replaceExtractionOps(): Unit = { + if (boxKind.boxedTypes.lengthCompare(1) == 0) { + // fast path for single-value boxes + allConsumers.foreach(extraction => extraction.postExtractionAdaptationOps(boxKind.boxedTypes.head) match { + case Nil => + toDelete ++= extraction.allInsns + case ops => + toReplace(extraction.consumer) = ops + toDelete ++= extraction.allInsns - extraction.consumer + }) + } else { + for (extraction <- allConsumers) { + val valueIndex = boxKind.extractedValueIndex(extraction) + val replacementOps = if (valueIndex == 0) { + val pops = boxKind.boxedTypes.tail.map(t => getPop(t.getSize)) + pops ::: extraction.postExtractionAdaptationOps(boxKind.boxedTypes.head) + } else { + var loadOps: List[AbstractInsnNode] = null + val consumeStack = boxKind.boxedTypes.zipWithIndex reverseMap { + case (tp, i) => + if (i == valueIndex) { + val resultSlot = getLocal(tp.getSize) + loadOps = new VarInsnNode(tp.getOpcode(ILOAD), resultSlot) :: extraction.postExtractionAdaptationOps(tp) + new VarInsnNode(tp.getOpcode(ISTORE), resultSlot) + } else { + getPop(tp.getSize) + } + } + consumeStack ::: loadOps + } + toReplace(extraction.consumer) = replacementOps + toDelete ++= extraction.allInsns - extraction.consumer + } + } + } + + checkCopyOpReplacements(allCreations, allConsumers, boxKind.boxedTypes, nextLocal, prodCons) match { + case Some((replacements, nextCopyOpLocal, reTypedLocals)) => + toReplace ++= replacements + updateLocalVariableTypes(reTypedLocals) + nextLocal = nextCopyOpLocal + replaceCreationOps() + replaceExtractionOps() + // Conservative (safe) value for stack growth. In every frame that initially has a multi-value + // box on the stack, the stack now contains all of the individual values. So for every eliminated + // box, the maxStack may be up to N-1 slots larger. + maxStackGrowth += boxKind.boxedTypes.length - 1 + + case None => + } + } + + val it = method.instructions.iterator + while (it.hasNext) { + val insn = it.next() + if (!knownHandled(insn)) BoxKind.valueCreationKind(insn, prodCons) match { + case Some((boxCreation, boxKind)) => + allCreationsConsumers(boxCreation, boxKind, prodCons) match { + case Some((allCreations, allConsumers)) => + val (escapingConsumers, boxConsumers) = allConsumers.partition(_.isEscaping) + if (boxConsumers.nonEmpty) { + for (c <- allCreations) knownHandled ++= c.allInsns + for (e <- allConsumers) knownHandled ++= e.allInsns + + val hasEscaping = escapingConsumers.nonEmpty + val hasWrite = allConsumers.exists(_.isWrite) + if (!hasEscaping && !hasWrite) { + // M2 -- see doc comment in the beginning of this file + // If both M1 and M2 can be applied, we prefer M2 because it doesn't introduce new locals. + replaceBoxOperationsMultipleCreations(allCreations, allConsumers, boxKind) + } else if (allCreations.size == 1 && (!hasEscaping || !boxKind.isMutable)) { + // M1 -- see doc comment in the beginning of this file + replaceBoxOperationsSingleCreation(allCreations.head, allConsumers, boxKind, keepBox = hasEscaping) + } + } + + case None => + } + + case None => + } + } + + def removeFromCallGraph(insn: AbstractInsnNode): Unit = insn match { + case mi: MethodInsnNode => callGraph.removeCallsite(mi, method) + case _ => + } + + for ((location, ops) <- toInsertBefore; op <- ops) + method.instructions.insertBefore(location, op) + + for ((oldOp, newOps) <- toReplace) { + for (newOp <- newOps) method.instructions.insertBefore(oldOp, newOp) + method.instructions.remove(oldOp) + removeFromCallGraph(oldOp) + } + + for (op <- toDelete) { + method.instructions.remove(op) + removeFromCallGraph(op) + } + + method.maxLocals = nextLocal + method.maxStack += maxStackGrowth + toInsertBefore.nonEmpty || toReplace.nonEmpty || toDelete.nonEmpty + } + } + + /** + * Given a box creations operation + * - find all ultimate consumers for the produced value. then: + * - for all consumed values, find all producer operations. check that all are box creations + * - recurse until reaching a fixpoint + * + * Returns a set of box creations and a set of box consumers. Note that the box consumers may + * contain [[EscapingConsumer]]s, even if there are multiple box creation operations. The callee + * will handle this case (and not attempt to eliminate the box). + */ + def allCreationsConsumers(initialCreation: BoxCreation, boxKind: BoxKind, prodCons: ProdConsAnalyzer): Option[(Set[BoxCreation], Set[BoxConsumer])] = { + var creations = Set(initialCreation) + var consumers = Set.empty[BoxConsumer] + + def addCreations(boxConsumer: BoxConsumer): Boolean = { + val newProds = boxConsumer.boxProducers(prodCons).filterNot(prod => creations.exists(_.producer == prod)) + newProds.forall(prod => boxKind.checkBoxCreation(prod, prodCons) match { + case Some(boxCreation) => + creations += boxCreation + addBoxConsumers(boxCreation) + + case _ => false + }) + } + + def addBoxConsumers(creation: BoxCreation): Boolean = { + val newCons = creation.boxConsumers(prodCons, ultimate = true).filterNot(cons => consumers.exists(_.consumer == cons)) + newCons.forall(cons => boxKind.checkBoxConsumer(cons, prodCons) match { + case Some(boxConsumer) => + consumers += boxConsumer + addCreations(boxConsumer) + + case _ => + creations.size <= 1 && { + // If there's a single box creation, the box operations can still be rewritten + consumers += EscapingConsumer(cons) + true + } + }) + } + + if (addBoxConsumers(initialCreation)) Some((creations, consumers)) + else None + } + + /** + * Takes two sets `initialProds` and `finalCons` such that all boxes produced by the first set + * are only consumed by an operation in the second set. + * + * Returns a map that replaces copy operations (ALOAD / ASTORE) between the producers and + * consumers with corresponding copy operations for the values stored in the box. The returned + * `Int` value returns the next free local variable slot. + * + * Examples: + * - for an Integer box, an ASTORE x is simply replaced by ISTORE x + * - for a pair of two references, an ASTORE x is replaced by `ASTORE x1; ASTORE x2` where x1 + * and x2 are fresh locals + * + * Not all copy operations can be supported: DUP only works for single-value boxes, the more + * exotic copy operations (DUP2_X2) are not supported (note that Scalac never emits them). If a + * copy operation cannot be replaced, this method returns `None`. + */ + def checkCopyOpReplacements(initialProds: Set[BoxCreation], finalCons: Set[BoxConsumer], valueTypes: List[Type], nextLocal: Int, prodCons: ProdConsAnalyzer): Option[(Map[AbstractInsnNode, List[AbstractInsnNode]], Int, Map[Int, Type])] = { + var replacements = Map.empty[AbstractInsnNode, List[AbstractInsnNode]] + var reTypedLocals = Map.empty[Int, Type] + + var nextCopyOpLocal = nextLocal + val newLocalsMap: mutable.LongMap[List[(Type, Int)]] = mutable.LongMap.empty + def newLocals(index: Int) = newLocalsMap.getOrElseUpdate(index, valueTypes match { + case List(t) if t.getSize == 1 => + reTypedLocals += index -> t + List((t, index)) + case _ => valueTypes.map(t => { + val newIndex = nextCopyOpLocal + nextCopyOpLocal += t.getSize + (t, newIndex) + }) + }) + + var replaceOK = true + val copyOps = new CopyOpsIterator(initialProds, finalCons, prodCons) + while (replaceOK && copyOps.hasNext) copyOps.next() match { + case vi: VarInsnNode => + val isLoad = vi.getOpcode == ALOAD + val typedVarOp = (tp: (Type, Int)) => { + val opc = tp._1.getOpcode(if (isLoad) ILOAD else ISTORE) + new VarInsnNode(opc, tp._2) + } + val locs = newLocals(vi.`var`) + replacements += vi -> (if (isLoad) locs.map(typedVarOp) else locs.reverseMap(typedVarOp)) + + case copyOp => + if (copyOp.getOpcode == DUP && valueTypes.lengthCompare(1) == 0) { + if (valueTypes.head.getSize == 2) + replacements += copyOp -> List(new InsnNode(DUP2)) + } else { + replaceOK = false + } + } + if (replaceOK) Some((replacements, nextCopyOpLocal, reTypedLocals)) else None + } + + /** + * For a set of box creation operations and a corresponding set of box consumer operations, + * this iterator returns all copy operations (load, store, dup) that are in between. + */ + class CopyOpsIterator(initialCreations: Set[BoxCreation], finalCons: Set[BoxConsumer], prodCons: ProdConsAnalyzer) extends Iterator[AbstractInsnNode] { + private var queue = mutable.Queue.empty[AbstractInsnNode] ++ initialCreations.iterator.flatMap(_.boxConsumers(prodCons, ultimate = false)) + + // a single copy operation can consume multiple producers: val a = if (b) box(1) else box(2). + // the `ASTORE a` has two producers (the two box operations). we need to handle it only once. + private val visited = mutable.Set.empty[AbstractInsnNode] + + private val boxConsumingOps = finalCons.map(_.consumer) + + @tailrec private def advanceToNextCopyOp(): Unit = { + if (queue.nonEmpty) { + val h = queue.front + if (visited(h) || boxConsumingOps(h)) { + queue.dequeue() + advanceToNextCopyOp() + } + } + } + + def hasNext: Boolean = { + advanceToNextCopyOp() + queue.nonEmpty + } + + def next(): AbstractInsnNode = { + advanceToNextCopyOp() + val r = queue.dequeue() + visited += r + queue ++= prodCons.consumersOfOutputsFrom(r) + r + } + } + + trait BoxKind { + def checkBoxCreation(insn: AbstractInsnNode, prodCons: ProdConsAnalyzer): Option[BoxCreation] + def checkBoxConsumer(insn: AbstractInsnNode, prodCons: ProdConsAnalyzer): Option[BoxConsumer] + def boxedTypes: List[Type] + def extractedValueIndex(extraction: BoxConsumer): Int + def isMutable: Boolean + } + + object BoxKind { + def valueCreationKind(insn: AbstractInsnNode, prodCons: ProdConsAnalyzer): Option[(BoxCreation, BoxKind)] = { + PrimitiveBox.checkPrimitiveBox(insn, None, prodCons) orElse + Ref.checkRefCreation(insn, None, prodCons) orElse + Tuple.checkTupleCreation(insn, None, prodCons) + } + + /** + * Check if `newOp` is part of a standard object construction pattern in which: + * + * NEW T + * DUP + * [load constructor args] + * INVOKESPECIAL T.init + * + * The method ensures that the entire construction pattern is closed in itself, without any + * branches going in or out. This is checked by looking at producers / consumers: + * - `DUP` is the only consumer of `NEW`, and vice versa + * - `DUP` the only producer for the receiver of the constructor call + * - The set of consumers of `DUP` without the constructor call is the same as + * the set of consumers of the value on the stack top after the constructor call + */ + def checkInstanceCreation(newOp: TypeInsnNode, prodCons: ProdConsAnalyzer): Option[(InsnNode, MethodInsnNode)] = { + val newCons = prodCons.consumersOfOutputsFrom(newOp) + if (newCons.size == 1 && newCons.head.getOpcode == DUP) { + val dupOp = newCons.head.asInstanceOf[InsnNode] + if (prodCons.producersForInputsOf(dupOp) == Set(newOp)) { + val dupCons = prodCons.consumersOfOutputsFrom(dupOp) + val initCalls = dupCons collect { + case mi: MethodInsnNode if mi.name == GenBCode.INSTANCE_CONSTRUCTOR_NAME && mi.owner == newOp.desc => mi + } + if (initCalls.size == 1) { + val initCall = initCalls.head + val numArgs = Type.getArgumentTypes(initCall.desc).length + val receiverProds = prodCons.producersForValueAt(initCall, prodCons.frameAt(initCall).stackTop - numArgs) + if (receiverProds == Set(dupOp)) { + val dupConsWithoutInit = dupCons - initCall + val afterInit = initCall.getNext + val stackTopAfterInit = prodCons.frameAt(afterInit).stackTop + val initializedInstanceCons = prodCons.consumersOfValueAt(afterInit, stackTopAfterInit) + if (initializedInstanceCons == dupConsWithoutInit && prodCons.producersForValueAt(afterInit, stackTopAfterInit) == Set(dupOp)) { + return Some((dupOp, initCall)) + } + } + } + } + } + None + } + + /** + * If `mi` is an invocation of a method on Predef, check if the receiver is a GETSTATIC of + * Predef.MODULE$ and return it. + */ + def checkReceiverPredefLoad(mi: MethodInsnNode, prodCons: ProdConsAnalyzer): Option[AbstractInsnNode] = { + val numArgs = Type.getArgumentTypes(mi.desc).length + val receiverProds = prodCons.producersForValueAt(mi, prodCons.frameAt(mi).stackTop - numArgs) + if (receiverProds.size == 1) { + val prod = receiverProds.head + if (isPredefLoad(prod) && prodCons.consumersOfOutputsFrom(prod) == Set(mi)) return Some(prod) + } + None + } + } + + case class PrimitiveBox(boxedType: Type, boxClass: InternalName) extends BoxKind { + import PrimitiveBox._ + def checkBoxCreation(insn: AbstractInsnNode, prodCons: ProdConsAnalyzer): Option[BoxCreation] = checkPrimitiveBox(insn, Some(this), prodCons).map(_._1) + def checkBoxConsumer(insn: AbstractInsnNode, prodCons: ProdConsAnalyzer): Option[BoxConsumer] = checkPrimitiveUnbox(insn, this, prodCons) + def boxedTypes: List[Type] = List(boxedType) + def extractedValueIndex(extraction: BoxConsumer): Int = 0 + def isMutable = false + } + + object PrimitiveBox { + private def boxedType(mi: MethodInsnNode) = Type.getArgumentTypes(mi.desc)(0) + + private def boxClass(mi: MethodInsnNode) = { + if (mi.name == GenBCode.INSTANCE_CONSTRUCTOR_NAME) mi.owner + else Type.getReturnType(mi.desc).getInternalName + } + + def checkPrimitiveBox(insn: AbstractInsnNode, expectedKind: Option[PrimitiveBox], prodCons: ProdConsAnalyzer): Option[(BoxCreation, PrimitiveBox)] = { + // mi is either a box factory or a box constructor invocation + def checkKind(mi: MethodInsnNode) = expectedKind match { + case Some(kind) => if (kind.boxClass == boxClass(mi)) expectedKind else None + case None => Some(PrimitiveBox(boxedType(mi), boxClass(mi))) + } + + insn match { + case mi: MethodInsnNode => + if (isScalaBox(mi) || isJavaBox(mi)) checkKind(mi).map((StaticFactory(mi, loadInitialValues = None), _)) + else if (isPredefAutoBox(mi)) + for (predefLoad <- BoxKind.checkReceiverPredefLoad(mi, prodCons); kind <- checkKind(mi)) + yield (ModuleFactory(predefLoad, mi), kind) + else None + + case ti: TypeInsnNode if ti.getOpcode == NEW => + for ((dupOp, initCall) <- BoxKind.checkInstanceCreation(ti, prodCons) if isPrimitiveBoxConstructor(initCall); kind <- checkKind(initCall)) + yield (InstanceCreation(ti, dupOp, initCall), kind) + + case _ => None + } + } + + def checkPrimitiveUnbox(insn: AbstractInsnNode, kind: PrimitiveBox, prodCons: ProdConsAnalyzer): Option[BoxConsumer] = { + def typeOK(mi: MethodInsnNode) = kind.boxedType == Type.getReturnType(mi.desc) + insn match { + case mi: MethodInsnNode => + if ((isScalaUnbox(mi) || isJavaUnbox(mi)) && typeOK(mi)) Some(StaticGetterOrInstanceRead(mi)) + else if (isPredefAutoUnbox(mi) && typeOK(mi)) BoxKind.checkReceiverPredefLoad(mi, prodCons).map(ModuleGetter(_, mi)) + else None + + case _ => None + } + } + } + + case class Ref(boxedType: Type, refClass: InternalName) extends BoxKind { + import Ref._ + def checkBoxCreation(insn: AbstractInsnNode, prodCons: ProdConsAnalyzer): Option[BoxCreation] = checkRefCreation(insn, Some(this), prodCons).map(_._1) + def checkBoxConsumer(insn: AbstractInsnNode, prodCons: ProdConsAnalyzer): Option[BoxConsumer] = checkRefConsumer(insn, this, prodCons) + def boxedTypes: List[Type] = List(boxedType) + def extractedValueIndex(extraction: BoxConsumer): Int = 0 + def isMutable = true + } + + object Ref { + private def boxedType(mi: MethodInsnNode): Type = runtimeRefClassBoxedType(mi.owner) + private def refClass(mi: MethodInsnNode): InternalName = mi.owner + private def loadZeroValue(refZeroCall: MethodInsnNode): List[AbstractInsnNode] = List(loadZeroForTypeSort(runtimeRefClassBoxedType(refZeroCall.owner).getSort)) + + def checkRefCreation(insn: AbstractInsnNode, expectedKind: Option[Ref], prodCons: ProdConsAnalyzer): Option[(BoxCreation, Ref)] = { + def checkKind(mi: MethodInsnNode): Option[Ref] = expectedKind match { + case Some(kind) => if (kind.refClass == refClass(mi)) expectedKind else None + case None => Some(Ref(boxedType(mi), refClass(mi))) + } + + insn match { + case mi: MethodInsnNode => + if (isRefCreate(mi)) checkKind(mi).map((StaticFactory(mi, loadInitialValues = None), _)) + else if (isRefZero(mi)) checkKind(mi).map((StaticFactory(mi, loadInitialValues = Some(loadZeroValue(mi))), _)) + else None + + case ti: TypeInsnNode if ti.getOpcode == NEW => + for ((dupOp, initCall) <- BoxKind.checkInstanceCreation(ti, prodCons) if isRuntimeRefConstructor(initCall); kind <- checkKind(initCall)) + yield (InstanceCreation(ti, dupOp, initCall), kind) + + case _ => None + } + } + + def checkRefConsumer(insn: AbstractInsnNode, kind: Ref, prodCons: ProdConsAnalyzer): Option[BoxConsumer] = insn match { + case fi: FieldInsnNode if fi.owner == kind.refClass && fi.name == "elem" => + if (fi.getOpcode == GETFIELD) Some(StaticGetterOrInstanceRead(fi)) + else if (fi.getOpcode == PUTFIELD) Some(StaticSetterOrInstanceWrite(fi)) + else None + + case _ => None + } + } + + case class Tuple(boxedTypes: List[Type], tupleClass: InternalName) extends BoxKind { + import Tuple._ + def checkBoxCreation(insn: AbstractInsnNode, prodCons: ProdConsAnalyzer): Option[BoxCreation] = checkTupleCreation(insn, Some(this), prodCons).map(_._1) + def checkBoxConsumer(insn: AbstractInsnNode, prodCons: ProdConsAnalyzer): Option[BoxConsumer] = checkTupleExtraction(insn, this, prodCons) + def extractedValueIndex(extraction: BoxConsumer): Int = extraction match { + case StaticGetterOrInstanceRead(mi: MethodInsnNode) => tupleGetterIndex(mi.name) + case PrimitiveBoxingGetter(mi) => tupleGetterIndex(mi.name) + case PrimitiveUnboxingGetter(mi, _) => tupleGetterIndex(mi.name) + case _ => throw new AssertionError(s"Expected tuple getter, found $extraction") + } + def isMutable = false + } + + object Tuple { + private def boxedTypes(mi: MethodInsnNode): List[Type] = Type.getArgumentTypes(mi.desc).toList + private def tupleClass(mi: MethodInsnNode): InternalName = mi.owner + + def checkTupleCreation(insn: AbstractInsnNode, expectedKind: Option[Tuple], prodCons: ProdConsAnalyzer): Option[(BoxCreation, Tuple)] = { + def checkKind(mi: MethodInsnNode): Option[Tuple] = expectedKind match { + case Some(kind) => if (kind.tupleClass == tupleClass(mi)) expectedKind else None + case None => Some(Tuple(boxedTypes(mi), tupleClass(mi))) + } + + insn match { + // no need to check for TupleN.apply: the compiler transforms case companion apply calls to constructor invocations + case ti: TypeInsnNode if ti.getOpcode == NEW => + for ((dupOp, initCall) <- BoxKind.checkInstanceCreation(ti, prodCons) if isTupleConstructor(initCall); kind <- checkKind(initCall)) + yield (InstanceCreation(ti, dupOp, initCall), kind) + + case _ => None + } + } + + private val specializedTupleClassR = "scala/Tuple[12]\\$mc[IJDCZ]{1,2}\\$sp".r + private def isSpecializedTupleClass(tupleClass: InternalName) = specializedTupleClassR.pattern.matcher(tupleClass).matches + + private val specializedTupleGetterR = "_[12]\\$mc[IJDCZ]\\$sp".r + private def isSpecializedTupleGetter(mi: MethodInsnNode) = specializedTupleGetterR.pattern.matcher(mi.name).matches + + private val tupleGetterR = "_\\d\\d?".r + private def isTupleGetter(mi: MethodInsnNode) = tupleGetterR.pattern.matcher(mi.name).matches + + def checkTupleExtraction(insn: AbstractInsnNode, kind: Tuple, prodCons: ProdConsAnalyzer): Option[BoxConsumer] = { + val expectedTupleClass = kind.tupleClass + insn match { + case mi: MethodInsnNode => + val tupleClass = mi.owner + if (isSpecializedTupleClass(expectedTupleClass)) { + val typeOK = tupleClass == expectedTupleClass || tupleClass == expectedTupleClass.substring(0, expectedTupleClass.indexOf('$')) + if (typeOK) { + if (isSpecializedTupleGetter(mi)) return Some(StaticGetterOrInstanceRead(mi)) + else if (isTupleGetter(mi)) return Some(PrimitiveBoxingGetter(mi)) + } + } else if (expectedTupleClass == tupleClass) { + if (isSpecializedTupleGetter(mi)) return Some(PrimitiveUnboxingGetter(mi, Type.getReturnType(mi.desc))) + else if (isTupleGetter(mi)) return Some(StaticGetterOrInstanceRead(mi)) + } + + case _ => + } + None + } + + private val getterIndexPattern = "_(\\d{1,2}).*".r + def tupleGetterIndex(getterName: String) = getterName match { case getterIndexPattern(i) => i.toInt - 1 } + } + + // TODO: add more + // case class ValueClass(valueClass: Type, valueType: Type) extends BoxKind + + sealed trait BoxCreation { + // to support box creation operations that don't consume an initial value from the stack, e.g., IntRef.zero + val loadInitialValues: Option[List[AbstractInsnNode]] + + /** + * The instruction that produces the box value; for instance creations, the `NEW` operation. + */ + def producer: AbstractInsnNode + + /** + * The instruction that consumes the boxed values; for instance creations, the `init` call. + */ + def valuesConsumer: MethodInsnNode = this match { + case StaticFactory(call, _) => call + case ModuleFactory(_, call) => call + case InstanceCreation(_, _, initCall) => initCall + } + + def allInsns: Set[AbstractInsnNode] = this match { + case StaticFactory(c, _) => Set(c) + case ModuleFactory(m, c) => Set(m, c) + case InstanceCreation(n, d, i) => Set(n, d, i) + } + + /** + * The consumers of the box produced by this box creation. If `ultimate` is true, then the + * final consumers are returned (e.g., an unbox operation), otherwise direct consumers (e.g., + * a store operation). + */ + def boxConsumers(prodCons: ProdConsAnalyzer, ultimate: Boolean): Set[AbstractInsnNode] = { + val startInsn = this match { + // for the non-transitive case (ultimate == false), it's important to start at the `dupOp`, + // not the `newOp` - look at the BoxCreation as a black box, get its consumers. + case InstanceCreation(_, dupOp, _) => dupOp + case _ => producer + } + val cons = if (ultimate) prodCons.ultimateConsumersOfOutputsFrom(startInsn) else prodCons.consumersOfOutputsFrom(startInsn) + this match { + case InstanceCreation(_, _, initCall) => cons - initCall + case _ => cons + } + } + } + + case class StaticFactory(producer: MethodInsnNode, loadInitialValues: Option[List[AbstractInsnNode]]) extends BoxCreation + case class ModuleFactory(moduleLoad: AbstractInsnNode, producer: MethodInsnNode) extends BoxCreation { + val loadInitialValues: Option[List[AbstractInsnNode]] = None + } + case class InstanceCreation(newOp: TypeInsnNode, dupOp: InsnNode, initCall: MethodInsnNode) extends BoxCreation { + def producer = newOp + val loadInitialValues: Option[List[AbstractInsnNode]] = None + } + + sealed trait BoxConsumer { + val consumer: AbstractInsnNode + + def allInsns: Set[AbstractInsnNode] = this match { + case ModuleGetter(m, c) => Set(m, c) + case _ => Set(consumer) + } + + /** + * The initial producers of the box value consumed by this box consumer + */ + def boxProducers(prodCons: ProdConsAnalyzer): Set[AbstractInsnNode] = { + val stackTop = prodCons.frameAt(consumer).stackTop + val slot = if (isWrite) stackTop - 1 else stackTop + prodCons.initialProducersForValueAt(consumer, slot) + } + + def isEscaping = this match { + case _: EscapingConsumer => true + case _ => false + } + + def isWrite = this match { + case _: StaticSetterOrInstanceWrite => true + case _ => false + } + + /** + * If this box consumer extracts a boxed value and applies a conversion, this method returns + * equivalent conversion operations. For example, invoking `_1$mcI$sp` on a non-specialized + * `Tuple2` extracts the Integer value and unboxes it. + */ + def postExtractionAdaptationOps(typeOfExtractedValue: Type): List[AbstractInsnNode] = this match { + case PrimitiveBoxingGetter(_) => List(getScalaBox(typeOfExtractedValue)) + case PrimitiveUnboxingGetter(_, unboxedPrimitive) => List(getScalaUnbox(unboxedPrimitive)) + case _ => Nil + } + } + + /** Static extractor (BoxesRunTime.unboxToInt) or GETFIELD or getter invocation */ + case class StaticGetterOrInstanceRead(consumer: AbstractInsnNode) extends BoxConsumer + /** A getter that boxes the returned value, e.g., `Tuple2$mcII$sp._1` */ + case class PrimitiveBoxingGetter(consumer: MethodInsnNode) extends BoxConsumer + /** A getter that unboxes the returned value, e.g., `Tuple2._1$mcI$sp` */ + case class PrimitiveUnboxingGetter(consumer: MethodInsnNode, unboxedPrimitive: Type) extends BoxConsumer + /** An extractor method in a Scala module, e.g., `Predef.Integer2int` */ + case class ModuleGetter(moduleLoad: AbstractInsnNode, consumer: MethodInsnNode) extends BoxConsumer + /** PUTFIELD or setter invocation */ + case class StaticSetterOrInstanceWrite(consumer: AbstractInsnNode) extends BoxConsumer + /** An unknown box consumer */ + case class EscapingConsumer(consumer: AbstractInsnNode) extends BoxConsumer +} diff --git a/src/compiler/scala/tools/nsc/backend/jvm/opt/ByteCodeRepository.scala b/src/compiler/scala/tools/nsc/backend/jvm/opt/ByteCodeRepository.scala index a5b85e54e7..f2ff73c44d 100644 --- a/src/compiler/scala/tools/nsc/backend/jvm/opt/ByteCodeRepository.scala +++ b/src/compiler/scala/tools/nsc/backend/jvm/opt/ByteCodeRepository.scala @@ -9,13 +9,12 @@ package opt import scala.tools.asm import asm.tree._ -import scala.collection.convert.decorateAsScala._ +import scala.collection.JavaConverters._ +import scala.collection.{concurrent, mutable} import scala.tools.asm.Attribute import scala.tools.nsc.backend.jvm.BackendReporting._ -import scala.tools.nsc.io.AbstractFile -import scala.tools.nsc.util.ClassFileLookup +import scala.tools.nsc.util.ClassPath import BytecodeUtils._ -import ByteCodeRepository._ import BTypes.InternalName import java.util.concurrent.atomic.AtomicLong @@ -24,58 +23,91 @@ import java.util.concurrent.atomic.AtomicLong * classpath. Parsed classes are cached in the `classes` map. * * @param classPath The compiler classpath where classfiles are searched and read from. - * @param classes Cache for parsed ClassNodes. Also stores the source of the bytecode: - * [[Classfile]] if read from `classPath`, [[CompilationUnit]] if the bytecode - * corresponds to a class being compiled. - * The `Long` field encodes the age of the node in the map, which allows removing - * old entries when the map grows too large. - * For Java classes in mixed compilation, the map contains an error message: no - * ClassNode is generated by the backend and also no classfile that could be parsed. */ -class ByteCodeRepository(val classPath: ClassFileLookup[AbstractFile], val isJavaSourceDefined: InternalName => Boolean, val classes: collection.concurrent.Map[InternalName, Either[ClassNotFound, (ClassNode, Source, Long)]]) { +class ByteCodeRepository[BT <: BTypes](val classPath: ClassPath, val btypes: BT) { + import btypes._ + + /** + * Contains ClassNodes and the canonical path of the source file path of classes being compiled in + * the current compilation run. + */ + val compilingClasses: concurrent.Map[InternalName, (ClassNode, String)] = recordPerRunCache(concurrent.TrieMap.empty) + + /** + * Cache for parsed ClassNodes. + * The `Long` field encodes the age of the node in the map, which allows removing old entries when + * the map grows too large (see limitCacheSize). + * For Java classes in mixed compilation, the map contains an error message: no ClassNode is + * generated by the backend and also no classfile that could be parsed. + */ + val parsedClasses: concurrent.Map[InternalName, Either[ClassNotFound, (ClassNode, Long)]] = recordPerRunCache(concurrent.TrieMap.empty) private val maxCacheSize = 1500 private val targetSize = 500 - private val idCounter = new AtomicLong(0) + private object lruCounter extends AtomicLong(0l) with collection.generic.Clearable { + def clear(): Unit = { this.set(0l) } + } + recordPerRunCache(lruCounter) /** * Prevent the code repository from growing too large. Profiling reveals that the average size * of a ClassNode is about 30 kb. I observed having 17k+ classes in the cache, i.e., 500 mb. - * - * We can only remove classes with `Source == Classfile`, those can be parsed again if requested. */ private def limitCacheSize(): Unit = { - if (classes.count(c => c._2.isRight && c._2.right.get._2 == Classfile) > maxCacheSize) { - val removeId = idCounter.get - targetSize - val toRemove = classes.iterator.collect({ - case (name, Right((_, Classfile, id))) if id < removeId => name - }).toList - toRemove foreach classes.remove + if (parsedClasses.size > maxCacheSize) { + // OK if multiple threads get here + val minimalLRU = parsedClasses.valuesIterator.collect({ + case Right((_, lru)) => lru + }).toList.sorted(Ordering.Long.reverse).drop(targetSize).headOption.getOrElse(Long.MaxValue) + parsedClasses retain { + case (_, Right((_, lru))) => lru > minimalLRU + case _ => false + } } } - def add(classNode: ClassNode, source: Source) = { - classes(classNode.name) = Right((classNode, source, idCounter.incrementAndGet())) + def add(classNode: ClassNode, sourceFilePath: Option[String]) = sourceFilePath match { + case Some(path) if path != "<no file>" => compilingClasses(classNode.name) = (classNode, path) + case _ => parsedClasses(classNode.name) = Right((classNode, lruCounter.incrementAndGet())) + } + + private def parsedClassNode(internalName: InternalName): Either[ClassNotFound, ClassNode] = { + val r = parsedClasses.get(internalName) match { + case Some(l @ Left(_)) => l + case Some(r @ Right((classNode, _))) => + parsedClasses(internalName) = Right((classNode, lruCounter.incrementAndGet())) + r + case None => + limitCacheSize() + val res = parseClass(internalName).map((_, lruCounter.incrementAndGet())) + parsedClasses(internalName) = res + res + } + r.map(_._1) } /** - * The class node and source for an internal name. If the class node is not yet available, it is - * parsed from the classfile on the compile classpath. + * The class node and source file path (if the class is being compiled) for an internal name. If + * the class node is not yet available, it is parsed from the classfile on the compile classpath. */ - def classNodeAndSource(internalName: InternalName): Either[ClassNotFound, (ClassNode, Source)] = { - val r = classes.getOrElseUpdate(internalName, { - limitCacheSize() - parseClass(internalName).map((_, Classfile, idCounter.incrementAndGet())) - }) - r.map(v => (v._1, v._2)) + def classNodeAndSourceFilePath(internalName: InternalName): Either[ClassNotFound, (ClassNode, Option[String])] = { + compilingClasses.get(internalName) match { + case Some((c, p)) => Right((c, Some(p))) + case _ => parsedClassNode(internalName).map((_, None)) + } } /** * The class node for an internal name. If the class node is not yet available, it is parsed from * the classfile on the compile classpath. */ - def classNode(internalName: InternalName): Either[ClassNotFound, ClassNode] = classNodeAndSource(internalName).map(_._1) + def classNode(internalName: InternalName): Either[ClassNotFound, ClassNode] = { + compilingClasses.get(internalName) match { + case Some((c, _)) => Right(c) + case None => parsedClassNode(internalName) + } + } /** * The field node for a field matching `name` and `descriptor`, accessed in class `classInternalName`. @@ -86,7 +118,6 @@ class ByteCodeRepository(val classPath: ClassFileLookup[AbstractFile], val isJav */ def fieldNode(classInternalName: InternalName, name: String, descriptor: String): Either[FieldNotFound, (FieldNode, InternalName)] = { def fieldNodeImpl(parent: InternalName): Either[FieldNotFound, (FieldNode, InternalName)] = { - def msg = s"The field node $name$descriptor could not be found in class $classInternalName or any of its superclasses." classNode(parent) match { case Left(e) => Left(FieldNotFound(name, descriptor, classInternalName, Some(e))) case Right(c) => @@ -105,33 +136,135 @@ class ByteCodeRepository(val classPath: ClassFileLookup[AbstractFile], val isJav * The method node for a method matching `name` and `descriptor`, accessed in class `ownerInternalNameOrArrayDescriptor`. * The declaration of the method may be in one of the parents. * + * Note that the JVM spec performs method lookup in two steps: resolution and selection. + * + * Method resolution, defined in jvms-5.4.3.3 and jvms-5.4.3.4, is the first step and is identical + * for all invocation styles (virtual, interface, special, static). If C is the receiver class + * in the invocation instruction: + * 1 find a matching method (name and descriptor) in C + * 2 then in C's superclasses + * 3 then find the maximally-specific matching superinterface methods, succeed if there's a + * single non-abstract one. static and private methods in superinterfaces are not considered. + * 4 then pick a random non-static, non-private superinterface method. + * 5 then fail. + * + * Note that for an `invokestatic` instruction, a method reference `B.m` may resolve to `A.m`, if + * class `B` doesn't specify a matching method `m`, but the parent `A` does. + * + * Selection depends on the invocation style and is defined in jvms-6.5. + * - invokestatic: invokes the resolved method + * - invokevirtual / invokeinterface: searches for an override of the resolved method starting + * at the dynamic receiver type. the search procedure is basically the same as in resolution, + * but it fails at 4 instead of picking a superinterface method at random. + * - invokespecial: if C is the receiver in the invocation instruction, searches for an override + * of the resolved method starting at + * - the superclass of the current class, if C is a superclass of the current class + * - C otherwise + * again, the search procedure is the same. + * + * In the method here we implement method *resolution*. Whether or not the returned method is + * actually invoked at runtime depends on the invocation instruction and the class hierarchy, so + * the users (e.g. the inliner) have to be aware of method selection. + * + * Note that the returned method may be abstract (ACC_ABSTRACT), native (ACC_NATIVE) or signature + * polymorphic (methods `invoke` and `invokeExact` in class `MethodHandles`). + * * @return The [[MethodNode]] of the requested method and the [[InternalName]] of its declaring - * class, or an error message if the method could not be found. + * class, or an error message if the method could not be found. An error message is also + * returned if method resolution results in multiple default methods. */ def methodNode(ownerInternalNameOrArrayDescriptor: String, name: String, descriptor: String): Either[MethodNotFound, (MethodNode, InternalName)] = { - // on failure, returns a list of class names that could not be found on the classpath - def methodNodeImpl(ownerInternalName: InternalName): Either[List[ClassNotFound], (MethodNode, InternalName)] = { - classNode(ownerInternalName) match { - case Left(e) => Left(List(e)) - case Right(c) => - c.methods.asScala.find(m => m.name == name && m.desc == descriptor) match { - case Some(m) => Right((m, ownerInternalName)) - case None => findInParents(Option(c.superName) ++: c.interfaces.asScala.toList, Nil) - } + def findMethod(c: ClassNode): Option[MethodNode] = c.methods.asScala.find(m => m.name == name && m.desc == descriptor) + + // https://docs.oracle.com/javase/specs/jvms/se8/html/jvms-2.html#jvms-2.9: "In Java SE 8, the only + // signature polymorphic methods are the invoke and invokeExact methods of the class MethodHandle. + def isSignaturePolymorphic(owner: InternalName) = owner == coreBTypes.jliMethodHandleRef.internalName && (name == "invoke" || name == "invokeExact") + + // Note: if `owner` is an interface, in the first iteration we search for a matching member in the interface itself. + // If that fails, the recursive invocation checks in the superclass (which is Object) with `publicInstanceOnly == true`. + // This is specified in jvms-5.4.3.4: interface method resolution only returns public, non-static methods of Object. + def findInSuperClasses(owner: ClassNode, publicInstanceOnly: Boolean = false): Either[ClassNotFound, Option[(MethodNode, InternalName)]] = { + findMethod(owner) match { + case Some(m) if !publicInstanceOnly || (isPublicMethod(m) && !isStaticMethod(m)) => Right(Some((m, owner.name))) + case None => + if (isSignaturePolymorphic(owner.name)) Right(Some((owner.methods.asScala.find(_.name == name).get, owner.name))) + else if (owner.superName == null) Right(None) + else classNode(owner.superName).flatMap(findInSuperClasses(_, isInterface(owner))) } } - // find the MethodNode in one of the parent classes - def findInParents(parents: List[InternalName], failedClasses: List[ClassNotFound]): Either[List[ClassNotFound], (MethodNode, InternalName)] = parents match { - case x :: xs => methodNodeImpl(x).left.flatMap(failed => findInParents(xs, failed ::: failedClasses)) - case Nil => Left(failedClasses) + def findInInterfaces(initialOwner: ClassNode): Either[ClassNotFound, Option[(MethodNode, InternalName)]] = { + val visited = mutable.Set.empty[InternalName] + val found = mutable.ListBuffer.empty[(MethodNode, ClassNode)] + + def findIn(owner: ClassNode): Option[ClassNotFound] = { + for (i <- owner.interfaces.asScala if !visited(i)) classNode(i) match { + case Left(e) => return Some(e) + case Right(c) => + visited += i + // abstract and static methods are excluded, see jvms-5.4.3.3 + for (m <- findMethod(c) if !isPrivateMethod(m) && !isStaticMethod(m)) found += ((m, c)) + val recursionResult = findIn(c) + if (recursionResult.isDefined) return recursionResult + } + None + } + + findIn(initialOwner) + + val result = + if (found.size <= 1) found.headOption + else { + val maxSpecific = found.filterNot({ + case (method, owner) => + isAbstractMethod(method) || { + val ownerTp = classBTypeFromClassNode(owner) + found exists { + case (other, otherOwner) => + (other ne method) && { + val otherTp = classBTypeFromClassNode(otherOwner) + otherTp.isSubtypeOf(ownerTp).get + } + } + } + }) + // (*) note that if there's no single, non-abstract, maximally-specific method, the jvm + // method resolution (jvms-5.4.3.3) returns any of the non-private, non-static parent + // methods at random (abstract or concrete). + // we chose not to do this here, to prevent the inliner from potentially inlining the + // wrong method. in other words, we guarantee that a concrete method is only returned if + // it resolves deterministically. + // however, there may be multiple abstract methods inherited. in this case we *do* want + // to return a result to allow performing accessibility checks in the inliner. note that + // for accessibility it does not matter which of these methods is return, as they are all + // non-private (i.e., public, protected is not possible, jvms-4.1). + // the remaining case (when there's no max-specific method, but some non-abstract one) + // does not occur in bytecode generated by scalac or javac. we return no result in this + // case. this may at worst prevent some optimizations from happening. + if (maxSpecific.size == 1) maxSpecific.headOption + else if (found.forall(p => isAbstractMethod(p._1))) found.headOption // (*) + else None + } + Right(result.map(p => (p._1, p._2.name))) } // In a MethodInsnNode, the `owner` field may be an array descriptor, for example when invoking `clone`. We don't have a method node to return in this case. - if (ownerInternalNameOrArrayDescriptor.charAt(0) == '[') - Left(MethodNotFound(name, descriptor, ownerInternalNameOrArrayDescriptor, Nil)) - else - methodNodeImpl(ownerInternalNameOrArrayDescriptor).left.map(MethodNotFound(name, descriptor, ownerInternalNameOrArrayDescriptor, _)) + if (ownerInternalNameOrArrayDescriptor.charAt(0) == '[') { + Left(MethodNotFound(name, descriptor, ownerInternalNameOrArrayDescriptor, None)) + } else { + def notFound(cnf: Option[ClassNotFound]) = Left(MethodNotFound(name, descriptor, ownerInternalNameOrArrayDescriptor, cnf)) + val res: Either[ClassNotFound, Option[(MethodNode, InternalName)]] = classNode(ownerInternalNameOrArrayDescriptor).flatMap(c => + findInSuperClasses(c) flatMap { + case None => findInInterfaces(c) + case res => Right(res) + } + ) + res match { + case Left(e) => notFound(Some(e)) + case Right(None) => notFound(None) + case Right(Some(res)) => Right(res) + } + } } private def parseClass(internalName: InternalName): Either[ClassNotFound, ClassNode] = { @@ -157,17 +290,7 @@ class ByteCodeRepository(val classPath: ClassFileLookup[AbstractFile], val isJav classNode } match { case Some(node) => Right(node) - case None => Left(ClassNotFound(internalName, isJavaSourceDefined(internalName))) + case None => Left(ClassNotFound(internalName, javaDefinedClasses(internalName))) } } } - -object ByteCodeRepository { - /** - * The source of a ClassNode in the ByteCodeRepository. Can be either [[CompilationUnit]] if the - * class is being compiled or [[Classfile]] if the class was parsed from the compilation classpath. - */ - sealed trait Source - object CompilationUnit extends Source - object Classfile extends Source -} diff --git a/src/compiler/scala/tools/nsc/backend/jvm/opt/BytecodeUtils.scala b/src/compiler/scala/tools/nsc/backend/jvm/opt/BytecodeUtils.scala index 7aadd2c466..bfd92cac5c 100644 --- a/src/compiler/scala/tools/nsc/backend/jvm/opt/BytecodeUtils.scala +++ b/src/compiler/scala/tools/nsc/backend/jvm/opt/BytecodeUtils.scala @@ -8,28 +8,29 @@ package backend.jvm package opt import scala.annotation.{tailrec, switch} + import scala.collection.mutable import scala.reflect.internal.util.Collections._ import scala.tools.asm.commons.CodeSizeEvaluator import scala.tools.asm.tree.analysis._ -import scala.tools.asm.{MethodWriter, ClassWriter, Label, Opcodes, Type} +import scala.tools.asm.{Label, Type} +import scala.tools.asm.Opcodes._ import scala.tools.asm.tree._ import GenBCode._ -import scala.collection.convert.decorateAsScala._ -import scala.collection.convert.decorateAsJava._ -import scala.tools.nsc.backend.jvm.BTypes._ +import scala.collection.JavaConverters._ +import scala.tools.nsc.backend.jvm.analysis.InstructionStackEffect object BytecodeUtils { // http://docs.oracle.com/javase/specs/jvms/se7/html/jvms-4.html#jvms-4.9.1 - final val maxJVMMethodSize = 65535 + final val maxJVMMethodSize = 65535 // 5% margin, more than enough for the instructions added by the inliner (store / load args, null check for instance methods) final val maxMethodSizeAfterInline = maxJVMMethodSize - (maxJVMMethodSize / 20) object Goto { def unapply(instruction: AbstractInsnNode): Option[JumpInsnNode] = { - if (instruction.getOpcode == Opcodes.GOTO) Some(instruction.asInstanceOf[JumpInsnNode]) + if (instruction.getOpcode == GOTO) Some(instruction.asInstanceOf[JumpInsnNode]) else None } } @@ -49,8 +50,9 @@ object BytecodeUtils { } object VarInstruction { - def unapply(instruction: AbstractInsnNode): Option[VarInsnNode] = { - if (isVarInstruction(instruction)) Some(instruction.asInstanceOf[VarInsnNode]) + def unapply(instruction: AbstractInsnNode): Option[(AbstractInsnNode, Int)] = { + if (isLoadStoreOrRet(instruction)) Some((instruction, instruction.asInstanceOf[VarInsnNode].`var`)) + else if (instruction.getOpcode == IINC) Some((instruction, instruction.asInstanceOf[IincInsnNode].`var`)) else None } @@ -59,30 +61,46 @@ object BytecodeUtils { def isJumpNonJsr(instruction: AbstractInsnNode): Boolean = { val op = instruction.getOpcode // JSR is deprecated in classfile version 50, disallowed in 51. historically, it was used to implement finally. - op == Opcodes.GOTO || isConditionalJump(instruction) + op == GOTO || isConditionalJump(instruction) } def isConditionalJump(instruction: AbstractInsnNode): Boolean = { val op = instruction.getOpcode - (op >= Opcodes.IFEQ && op <= Opcodes.IF_ACMPNE) || op == Opcodes.IFNULL || op == Opcodes.IFNONNULL + (op >= IFEQ && op <= IF_ACMPNE) || op == IFNULL || op == IFNONNULL } def isReturn(instruction: AbstractInsnNode): Boolean = { val op = instruction.getOpcode - op >= Opcodes.IRETURN && op <= Opcodes.RETURN + op >= IRETURN && op <= RETURN } def isLoad(instruction: AbstractInsnNode): Boolean = { val op = instruction.getOpcode - op >= Opcodes.ILOAD && op <= Opcodes.ALOAD + op >= ILOAD && op <= ALOAD } def isStore(instruction: AbstractInsnNode): Boolean = { val op = instruction.getOpcode - op >= Opcodes.ISTORE && op <= Opcodes.ASTORE + op >= ISTORE && op <= ASTORE + } + + def isLoadStoreOrRet(instruction: AbstractInsnNode): Boolean = isLoad(instruction) || isStore(instruction) || instruction.getOpcode == RET + + def isLoadOrStore(instruction: AbstractInsnNode): Boolean = isLoad(instruction) || isStore(instruction) + + def isNonVirtualCall(instruction: AbstractInsnNode): Boolean = { + val op = instruction.getOpcode + op == INVOKESPECIAL || op == INVOKESTATIC } - def isVarInstruction(instruction: AbstractInsnNode): Boolean = isLoad(instruction) || isStore(instruction) + def isVirtualCall(instruction: AbstractInsnNode): Boolean = { + val op = instruction.getOpcode + op == INVOKEVIRTUAL || op == INVOKEINTERFACE + } + + def isCall(instruction: AbstractInsnNode): Boolean = { + isNonVirtualCall(instruction) || isVirtualCall(instruction) + } def isExecutable(instruction: AbstractInsnNode): Boolean = instruction.getOpcode >= 0 @@ -90,27 +108,40 @@ object BytecodeUtils { methodNode.name == INSTANCE_CONSTRUCTOR_NAME || methodNode.name == CLASS_CONSTRUCTOR_NAME } - def isStaticMethod(methodNode: MethodNode): Boolean = (methodNode.access & Opcodes.ACC_STATIC) != 0 + def isPublicMethod(methodNode: MethodNode): Boolean = (methodNode.access & ACC_PUBLIC) != 0 - def isAbstractMethod(methodNode: MethodNode): Boolean = (methodNode.access & Opcodes.ACC_ABSTRACT) != 0 + def isPrivateMethod(methodNode: MethodNode): Boolean = (methodNode.access & ACC_PRIVATE) != 0 - def isSynchronizedMethod(methodNode: MethodNode): Boolean = (methodNode.access & Opcodes.ACC_SYNCHRONIZED) != 0 + def isStaticMethod(methodNode: MethodNode): Boolean = (methodNode.access & ACC_STATIC) != 0 - def isNativeMethod(methodNode: MethodNode): Boolean = (methodNode.access & Opcodes.ACC_NATIVE) != 0 + def isAbstractMethod(methodNode: MethodNode): Boolean = (methodNode.access & ACC_ABSTRACT) != 0 - def isFinalClass(classNode: ClassNode): Boolean = (classNode.access & Opcodes.ACC_FINAL) != 0 + def isSynchronizedMethod(methodNode: MethodNode): Boolean = (methodNode.access & ACC_SYNCHRONIZED) != 0 - def isFinalMethod(methodNode: MethodNode): Boolean = (methodNode.access & (Opcodes.ACC_FINAL | Opcodes.ACC_PRIVATE | Opcodes.ACC_STATIC)) != 0 + def isNativeMethod(methodNode: MethodNode): Boolean = (methodNode.access & ACC_NATIVE) != 0 - def isStrictfpMethod(methodNode: MethodNode): Boolean = (methodNode.access & Opcodes.ACC_STRICT) != 0 + def hasCallerSensitiveAnnotation(methodNode: MethodNode): Boolean = methodNode.visibleAnnotations != null && methodNode.visibleAnnotations.asScala.exists(_.desc == "Lsun/reflect/CallerSensitive;") + + def isFinalClass(classNode: ClassNode): Boolean = (classNode.access & ACC_FINAL) != 0 + + def isInterface(classNode: ClassNode): Boolean = (classNode.access & ACC_INTERFACE) != 0 + + def isFinalMethod(methodNode: MethodNode): Boolean = (methodNode.access & (ACC_FINAL | ACC_PRIVATE | ACC_STATIC)) != 0 + + def isStrictfpMethod(methodNode: MethodNode): Boolean = (methodNode.access & ACC_STRICT) != 0 def isReference(t: Type) = t.getSort == Type.OBJECT || t.getSort == Type.ARRAY - def nextExecutableInstruction(instruction: AbstractInsnNode, alsoKeep: AbstractInsnNode => Boolean = Set()): Option[AbstractInsnNode] = { - var result = instruction - do { result = result.getNext } - while (result != null && !isExecutable(result) && !alsoKeep(result)) - Option(result) + @tailrec def nextExecutableInstruction(insn: AbstractInsnNode, alsoKeep: AbstractInsnNode => Boolean = Set()): Option[AbstractInsnNode] = { + val next = insn.getNext + if (next == null || isExecutable(next) || alsoKeep(next)) Option(next) + else nextExecutableInstruction(next, alsoKeep) + } + + @tailrec def nextExecutableInstructionOrLabel(insn: AbstractInsnNode): Option[AbstractInsnNode] = { + val next = insn.getNext + if (next == null || isExecutable(next) || next.isInstanceOf[LabelNode]) Option(next) + else nextExecutableInstructionOrLabel(next) } def sameTargetExecutableInstruction(a: JumpInsnNode, b: JumpInsnNode): Boolean = { @@ -124,14 +155,14 @@ object BytecodeUtils { def removeJumpAndAdjustStack(method: MethodNode, jump: JumpInsnNode) { val instructions = method.instructions val op = jump.getOpcode - if ((op >= Opcodes.IFEQ && op <= Opcodes.IFGE) || op == Opcodes.IFNULL || op == Opcodes.IFNONNULL) { + if ((op >= IFEQ && op <= IFLE) || op == IFNULL || op == IFNONNULL) { instructions.insert(jump, getPop(1)) - } else if ((op >= Opcodes.IF_ICMPEQ && op <= Opcodes.IF_ICMPLE) || op == Opcodes.IF_ACMPEQ || op == Opcodes.IF_ACMPNE) { + } else if ((op >= IF_ICMPEQ && op <= IF_ICMPLE) || op == IF_ACMPEQ || op == IF_ACMPNE) { instructions.insert(jump, getPop(1)) instructions.insert(jump, getPop(1)) } else { // we can't remove JSR: its execution does not only jump, it also adds a return address to the stack - assert(jump.getOpcode == Opcodes.GOTO) + assert(jump.getOpcode == GOTO) } instructions.remove(jump) } @@ -148,37 +179,61 @@ object BytecodeUtils { } def negateJumpOpcode(jumpOpcode: Int): Int = (jumpOpcode: @switch) match { - case Opcodes.IFEQ => Opcodes.IFNE - case Opcodes.IFNE => Opcodes.IFEQ + case IFEQ => IFNE + case IFNE => IFEQ + + case IFLT => IFGE + case IFGE => IFLT - case Opcodes.IFLT => Opcodes.IFGE - case Opcodes.IFGE => Opcodes.IFLT + case IFGT => IFLE + case IFLE => IFGT - case Opcodes.IFGT => Opcodes.IFLE - case Opcodes.IFLE => Opcodes.IFGT + case IF_ICMPEQ => IF_ICMPNE + case IF_ICMPNE => IF_ICMPEQ - case Opcodes.IF_ICMPEQ => Opcodes.IF_ICMPNE - case Opcodes.IF_ICMPNE => Opcodes.IF_ICMPEQ + case IF_ICMPLT => IF_ICMPGE + case IF_ICMPGE => IF_ICMPLT - case Opcodes.IF_ICMPLT => Opcodes.IF_ICMPGE - case Opcodes.IF_ICMPGE => Opcodes.IF_ICMPLT + case IF_ICMPGT => IF_ICMPLE + case IF_ICMPLE => IF_ICMPGT - case Opcodes.IF_ICMPGT => Opcodes.IF_ICMPLE - case Opcodes.IF_ICMPLE => Opcodes.IF_ICMPGT + case IF_ACMPEQ => IF_ACMPNE + case IF_ACMPNE => IF_ACMPEQ - case Opcodes.IF_ACMPEQ => Opcodes.IF_ACMPNE - case Opcodes.IF_ACMPNE => Opcodes.IF_ACMPEQ + case IFNULL => IFNONNULL + case IFNONNULL => IFNULL + } - case Opcodes.IFNULL => Opcodes.IFNONNULL - case Opcodes.IFNONNULL => Opcodes.IFNULL + def isSize2LoadOrStore(opcode: Int): Boolean = (opcode: @switch) match { + case LLOAD | DLOAD | LSTORE | DSTORE => true + case _ => false } def getPop(size: Int): InsnNode = { - val op = if (size == 1) Opcodes.POP else Opcodes.POP2 + val op = if (size == 1) POP else POP2 new InsnNode(op) } - def instructionResultSize(instruction: AbstractInsnNode) = InstructionResultSize(instruction) + def instructionResultSize(insn: AbstractInsnNode) = InstructionStackEffect.prod(InstructionStackEffect.forClassfile(insn)) + + def loadZeroForTypeSort(sort: Int) = (sort: @switch) match { + case Type.BOOLEAN | + Type.BYTE | + Type.CHAR | + Type.SHORT | + Type.INT => new InsnNode(ICONST_0) + case Type.LONG => new InsnNode(LCONST_0) + case Type.FLOAT => new InsnNode(FCONST_0) + case Type.DOUBLE => new InsnNode(DCONST_0) + case Type.OBJECT => new InsnNode(ACONST_NULL) + } + + /** + * The number of local variable slots used for parameters and for the `this` reference. + */ + def parametersSize(methodNode: MethodNode): Int = { + (Type.getArgumentsAndReturnSizes(methodNode.desc) >> 2) - (if (isStaticMethod(methodNode)) 1 else 0) + } def labelReferences(method: MethodNode): Map[LabelNode, Set[AnyRef]] = { val res = mutable.Map.empty[LabelNode, Set[AnyRef]] @@ -222,29 +277,6 @@ object BytecodeUtils { } } - /** - * In order to run an Analyzer, the maxLocals / maxStack fields need to be available. The ASM - * framework only computes these values during bytecode generation. - * - * Since there's currently no better way, we run a bytecode generator on the method and extract - * the computed values. This required changes to the ASM codebase: - * - the [[MethodWriter]] class was made public - * - accessors for maxLocals / maxStack were added to the MethodWriter class - * - * We could probably make this faster (and allocate less memory) by hacking the ASM framework - * more: create a subclass of MethodWriter with a /dev/null byteVector. Another option would be - * to create a separate visitor for computing those values, duplicating the functionality from the - * MethodWriter. - */ - def computeMaxLocalsMaxStack(method: MethodNode): Unit = { - val cw = new ClassWriter(ClassWriter.COMPUTE_MAXS) - val excs = method.exceptions.asScala.toArray - val mw = cw.visitMethod(method.access, method.name, method.desc, method.signature, excs).asInstanceOf[MethodWriter] - method.accept(mw) - method.maxLocals = mw.getMaxLocals - method.maxStack = mw.getMaxStack - } - def codeSizeOKForInlining(caller: MethodNode, callee: MethodNode): Boolean = { // Looking at the implementation of CodeSizeEvaluator, all instructions except tableswitch and // lookupswitch are <= 8 bytes. These should be rare enough for 8 to be an OK rough upper bound. @@ -289,34 +321,36 @@ object BytecodeUtils { } /** - * Clone the instructions in `methodNode` into a new [[InsnList]], mapping labels according to - * the `labelMap`. Returns the new instruction list and a map from old to new instructions. - */ - def cloneInstructions(methodNode: MethodNode, labelMap: Map[LabelNode, LabelNode]): (InsnList, Map[AbstractInsnNode, AbstractInsnNode]) = { - val javaLabelMap = labelMap.asJava - val result = new InsnList - var map = Map.empty[AbstractInsnNode, AbstractInsnNode] - for (ins <- methodNode.instructions.iterator.asScala) { - val cloned = ins.clone(javaLabelMap) - result add cloned - map += ((ins, cloned)) - } - (result, map) - } - - /** * Clone the local variable descriptors of `methodNode` and map their `start` and `end` labels * according to the `labelMap`. */ - def cloneLocalVariableNodes(methodNode: MethodNode, labelMap: Map[LabelNode, LabelNode], prefix: String): List[LocalVariableNode] = { - methodNode.localVariables.iterator().asScala.map(localVariable => new LocalVariableNode( - prefix + localVariable.name, - localVariable.desc, - localVariable.signature, - labelMap(localVariable.start), - labelMap(localVariable.end), - localVariable.index - )).toList + def cloneLocalVariableNodes(methodNode: MethodNode, labelMap: Map[LabelNode, LabelNode], calleeMethodName: String, shift: Int): List[LocalVariableNode] = { + methodNode.localVariables.iterator().asScala.map(localVariable => { + val name = + if (calleeMethodName.length + localVariable.name.length < BTypes.InlinedLocalVariablePrefixMaxLenght) { + calleeMethodName + "_" + localVariable.name + } else { + val parts = localVariable.name.split("_").toVector + val (methNames, varName) = (calleeMethodName +: parts.init, parts.last) + // keep at least 5 characters per method name + val maxNumMethNames = BTypes.InlinedLocalVariablePrefixMaxLenght / 5 + val usedMethNames = + if (methNames.length < maxNumMethNames) methNames + else { + val half = maxNumMethNames / 2 + methNames.take(half) ++ methNames.takeRight(half) + } + val charsPerMethod = BTypes.InlinedLocalVariablePrefixMaxLenght / usedMethNames.length + usedMethNames.foldLeft("")((res, methName) => res + methName.take(charsPerMethod) + "_") + varName + } + new LocalVariableNode( + name, + localVariable.desc, + localVariable.signature, + labelMap(localVariable.start), + labelMap(localVariable.end), + localVariable.index + shift) + }).toList } /** @@ -344,23 +378,14 @@ object BytecodeUtils { * method which explains the issue with such phantom values. */ def fixLoadedNothingOrNullValue(loadedType: Type, loadInstr: AbstractInsnNode, methodNode: MethodNode, bTypes: BTypes): Unit = { - if (loadedType == bTypes.coreBTypes.RT_NOTHING.toASMType) { - methodNode.instructions.insert(loadInstr, new InsnNode(Opcodes.ATHROW)) - } else if (loadedType == bTypes.coreBTypes.RT_NULL.toASMType) { - methodNode.instructions.insert(loadInstr, new InsnNode(Opcodes.ACONST_NULL)) - methodNode.instructions.insert(loadInstr, new InsnNode(Opcodes.POP)) + if (loadedType == bTypes.coreBTypes.srNothingRef.toASMType) { + methodNode.instructions.insert(loadInstr, new InsnNode(ATHROW)) + } else if (loadedType == bTypes.coreBTypes.srNullRef.toASMType) { + methodNode.instructions.insert(loadInstr, new InsnNode(ACONST_NULL)) + methodNode.instructions.insert(loadInstr, new InsnNode(POP)) } } - /** - * A wrapper to make ASM's Analyzer a bit easier to use. - */ - class AsmAnalyzer[V <: Value](methodNode: MethodNode, classInternalName: InternalName, interpreter: Interpreter[V] = new BasicInterpreter) { - val analyzer = new Analyzer(interpreter) - analyzer.analyze(classInternalName, methodNode) - def frameAt(instruction: AbstractInsnNode): Frame[V] = analyzer.frameAt(instruction, methodNode) - } - implicit class AnalyzerExtensions[V <: Value](val analyzer: Analyzer[V]) extends AnyVal { def frameAt(instruction: AbstractInsnNode, methodNode: MethodNode): Frame[V] = analyzer.getFrames()(methodNode.instructions.indexOf(instruction)) } diff --git a/src/compiler/scala/tools/nsc/backend/jvm/opt/CallGraph.scala b/src/compiler/scala/tools/nsc/backend/jvm/opt/CallGraph.scala index 96455c0e38..a740ca525c 100644 --- a/src/compiler/scala/tools/nsc/backend/jvm/opt/CallGraph.scala +++ b/src/compiler/scala/tools/nsc/backend/jvm/opt/CallGraph.scala @@ -7,182 +7,320 @@ package scala.tools.nsc package backend.jvm package opt +import scala.collection.immutable.IntMap import scala.reflect.internal.util.{NoPosition, Position} -import scala.tools.asm.tree.analysis.{Value, Analyzer, BasicInterpreter} -import scala.tools.asm.{Opcodes, Type, Handle} +import scala.tools.asm.{Handle, Opcodes, Type} import scala.tools.asm.tree._ -import scala.collection.concurrent -import scala.collection.convert.decorateAsScala._ -import scala.tools.nsc.backend.jvm.BTypes.InternalName +import scala.collection.{concurrent, mutable} +import scala.collection.JavaConverters._ +import scala.tools.nsc.backend.jvm.BTypes.{InternalName, MethodInlineInfo} import scala.tools.nsc.backend.jvm.BackendReporting._ -import scala.tools.nsc.backend.jvm.analysis.{NotNull, NullnessAnalyzer} -import ByteCodeRepository.{Source, CompilationUnit} +import scala.tools.nsc.backend.jvm.analysis._ import BytecodeUtils._ class CallGraph[BT <: BTypes](val btypes: BT) { import btypes._ + import backendUtils._ - val callsites: concurrent.Map[MethodInsnNode, Callsite] = recordPerRunCache(concurrent.TrieMap.empty) + /** + * The call graph contains the callsites in the program being compiled. + * + * Indexing the call graph by the containing MethodNode and the invocation MethodInsnNode allows + * finding callsites efficiently. For example, an inlining heuristic might want to know all + * callsites within a callee method. + * + * Note that the call graph is not guaranteed to be complete: callsites may be missing. In + * particular, if a method is very large, all of its callsites might not be in the hash map. + * The reason is that adding a method to the call graph requires running an ASM analyzer, which + * can be too slow. + * + * Note that call graph entries (Callsite instances) keep a reference to the invocation + * MethodInsnNode, which keeps all AbstractInsnNodes of the method reachable. Adding classes + * from the classpath to the call graph (in addition to classes being compiled) may prevent + * method instruction nodes from being GCd. The ByteCodeRepository has a fixed size cache for + * parsed ClassNodes - keeping all ClassNodes alive consumed too much memory. + * The call graph is less problematic because only methods being called are kept alive, not entire + * classes. But we should keep an eye on this. + */ + val callsites: mutable.Map[MethodNode, Map[MethodInsnNode, Callsite]] = recordPerRunCache(concurrent.TrieMap.empty withDefaultValue Map.empty) + + /** + * Closure instantiations in the program being compiled. + * + * Indexing closure instantiations by the containing MethodNode is beneficial for the closure + * optimizer: finding callsites to re-write requires running a producers-consumers analysis on + * the method. Here the closure instantiations are already grouped by method. + */ + val closureInstantiations: mutable.Map[MethodNode, Map[InvokeDynamicInsnNode, ClosureInstantiation]] = recordPerRunCache(concurrent.TrieMap.empty withDefaultValue Map.empty) + + def removeCallsite(invocation: MethodInsnNode, methodNode: MethodNode): Option[Callsite] = { + val methodCallsites = callsites(methodNode) + val newCallsites = methodCallsites - invocation + if (newCallsites.isEmpty) callsites.remove(methodNode) + else callsites(methodNode) = newCallsites + methodCallsites.get(invocation) + } + + def addCallsite(callsite: Callsite): Unit = { + val methodCallsites = callsites(callsite.callsiteMethod) + callsites(callsite.callsiteMethod) = methodCallsites + (callsite.callsiteInstruction -> callsite) + } - val closureInstantiations: concurrent.Map[InvokeDynamicInsnNode, ClosureInstantiation] = recordPerRunCache(concurrent.TrieMap.empty) + def containsCallsite(callsite: Callsite): Boolean = callsites(callsite.callsiteMethod) contains callsite.callsiteInstruction + def findCallSite(method: MethodNode, call: MethodInsnNode): Option[Callsite] = callsites.getOrElse(method, Map.empty).get(call) + + def removeClosureInstantiation(indy: InvokeDynamicInsnNode, methodNode: MethodNode): Option[ClosureInstantiation] = { + val methodClosureInits = closureInstantiations(methodNode) + val newClosureInits = methodClosureInits - indy + if (newClosureInits.isEmpty) closureInstantiations.remove(methodNode) + else closureInstantiations(methodNode) = newClosureInits + methodClosureInits.get(indy) + } + + def addClosureInstantiation(closureInit: ClosureInstantiation) = { + val methodClosureInits = closureInstantiations(closureInit.ownerMethod) + closureInstantiations(closureInit.ownerMethod) = methodClosureInits + (closureInit.lambdaMetaFactoryCall.indy -> closureInit) + } def addClass(classNode: ClassNode): Unit = { val classType = classBTypeFromClassNode(classNode) - for { - m <- classNode.methods.asScala - (calls, closureInits) = analyzeCallsites(m, classType) - } { - calls foreach (callsite => callsites(callsite.callsiteInstruction) = callsite) - closureInits foreach (lmf => closureInstantiations(lmf.indy) = ClosureInstantiation(lmf, m, classType)) - } + classNode.methods.asScala.foreach(addMethod(_, classType)) } - /** - * Returns a list of callsites in the method, plus a list of closure instantiation indy instructions. - */ - def analyzeCallsites(methodNode: MethodNode, definingClass: ClassBType): (List[Callsite], List[LambdaMetaFactoryCall]) = { + def addIfMissing(methodNode: MethodNode, definingClass: ClassBType): Unit = { + if (!callsites.contains(methodNode)) addMethod(methodNode, definingClass) + } - case class CallsiteInfo(safeToInline: Boolean, safeToRewrite: Boolean, - annotatedInline: Boolean, annotatedNoInline: Boolean, - warning: Option[CalleeInfoWarning]) + def addMethod(methodNode: MethodNode, definingClass: ClassBType): Unit = { + if (!BytecodeUtils.isAbstractMethod(methodNode) && !BytecodeUtils.isNativeMethod(methodNode)) { + // TODO: run dataflow analyses to make the call graph more precise + // - producers to get forwarded parameters (ForwardedParam) + // - typeAnalysis for more precise argument types, more precise callee + + // For now we run a NullnessAnalyzer. It is used to determine if the receiver of an instance + // call is known to be not-null, in which case we don't have to emit a null check when inlining. + // It is also used to get the stack height at the call site. + + val analyzer = { + if (compilerSettings.optNullnessTracking && AsmAnalyzer.sizeOKForNullness(methodNode)) { + Some(new AsmAnalyzer(methodNode, definingClass.internalName, new NullnessAnalyzer(btypes, methodNode))) + } else if (AsmAnalyzer.sizeOKForBasicValue(methodNode)) { + Some(new AsmAnalyzer(methodNode, definingClass.internalName)) + } else None + } - /** - * Analyze a callsite and gather meta-data that can be used for inlining decisions. - */ - def analyzeCallsite(calleeMethodNode: MethodNode, calleeDeclarationClassBType: ClassBType, receiverTypeInternalName: InternalName, calleeSource: Source): CallsiteInfo = { - val methodSignature = calleeMethodNode.name + calleeMethodNode.desc + // if the method is too large to run an analyzer, it is not added to the call graph + if (analyzer.nonEmpty) { + val Some(a) = analyzer + def receiverNotNullByAnalysis(call: MethodInsnNode, numArgs: Int) = a.analyzer match { + case nullnessAnalyzer: NullnessAnalyzer => + val frame = nullnessAnalyzer.frameAt(call, methodNode) + frame.getStack(frame.getStackSize - 1 - numArgs) eq NotNullValue + case _ => false + } - try { - // The inlineInfo.methodInfos of a ClassBType holds an InlineInfo for each method *declared* - // within a class (not for inherited methods). Since we already have the classBType of the - // callee, we only check there for the methodInlineInfo, we should find it there. - calleeDeclarationClassBType.info.orThrow.inlineInfo.methodInfos.get(methodSignature) match { - case Some(methodInlineInfo) => - val canInlineFromSource = compilerSettings.YoptInlineGlobal || calleeSource == CompilationUnit + var methodCallsites = Map.empty[MethodInsnNode, Callsite] + var methodClosureInstantiations = Map.empty[InvokeDynamicInsnNode, ClosureInstantiation] + + // lazy so it is only computed if actually used by computeArgInfos + lazy val prodCons = new ProdConsAnalyzer(methodNode, definingClass.internalName) + + methodNode.instructions.iterator.asScala foreach { + case call: MethodInsnNode if a.frameAt(call) != null => // skips over unreachable code + val callee: Either[OptimizerWarning, Callee] = for { + (method, declarationClass) <- byteCodeRepository.methodNode(call.owner, call.name, call.desc): Either[OptimizerWarning, (MethodNode, InternalName)] + (declarationClassNode, calleeSourceFilePath) <- byteCodeRepository.classNodeAndSourceFilePath(declarationClass): Either[OptimizerWarning, (ClassNode, Option[String])] + } yield { + val declarationClassBType = classBTypeFromClassNode(declarationClassNode) + val info = analyzeCallsite(method, declarationClassBType, call, calleeSourceFilePath) + import info._ + Callee( + callee = method, + calleeDeclarationClass = declarationClassBType, + isStaticallyResolved = isStaticallyResolved, + sourceFilePath = sourceFilePath, + annotatedInline = annotatedInline, + annotatedNoInline = annotatedNoInline, + samParamTypes = info.samParamTypes, + calleeInfoWarning = warning) + } - val isAbstract = BytecodeUtils.isAbstractMethod(calleeMethodNode) + val argInfos = computeArgInfos(callee, call, prodCons) - // (1) A non-final method can be safe to inline if the receiver type is a final subclass. Example: - // class A { @inline def f = 1 }; object B extends A; B.f // can be inlined - // - // TODO: type analysis can render more calls statically resolved. Example: - // new A.f // can be inlined, the receiver type is known to be exactly A. - val isStaticallyResolved: Boolean = { - methodInlineInfo.effectivelyFinal || - classBTypeFromParsedClassfile(receiverTypeInternalName).info.orThrow.inlineInfo.isEffectivelyFinal // (1) + val receiverNotNull = call.getOpcode == Opcodes.INVOKESTATIC || { + val numArgs = Type.getArgumentTypes(call.desc).length + receiverNotNullByAnalysis(call, numArgs) } - val isRewritableTraitCall = isStaticallyResolved && methodInlineInfo.traitMethodWithStaticImplementation - - val warning = calleeDeclarationClassBType.info.orThrow.inlineInfo.warning.map( - MethodInlineInfoIncomplete(calleeDeclarationClassBType.internalName, calleeMethodNode.name, calleeMethodNode.desc, _)) - - // (1) For invocations of final trait methods, the callee isStaticallyResolved but also - // abstract. Such a callee is not safe to inline - it needs to be re-written to the - // static impl method first (safeToRewrite). - // (2) Final trait methods can be rewritten from the interface to the static implementation - // method to enable inlining. - CallsiteInfo( - safeToInline = - canInlineFromSource && - isStaticallyResolved && // (1) - !isAbstract && - !BytecodeUtils.isConstructor(calleeMethodNode) && - !BytecodeUtils.isNativeMethod(calleeMethodNode), - safeToRewrite = canInlineFromSource && isRewritableTraitCall, // (2) - annotatedInline = methodInlineInfo.annotatedInline, - annotatedNoInline = methodInlineInfo.annotatedNoInline, - warning = warning) - - case None => - val warning = MethodInlineInfoMissing(calleeDeclarationClassBType.internalName, calleeMethodNode.name, calleeMethodNode.desc, calleeDeclarationClassBType.info.orThrow.inlineInfo.warning) - CallsiteInfo(false, false, false, false, Some(warning)) + methodCallsites += call -> Callsite( + callsiteInstruction = call, + callsiteMethod = methodNode, + callsiteClass = definingClass, + callee = callee, + argInfos = argInfos, + callsiteStackHeight = a.frameAt(call).getStackSize, + receiverKnownNotNull = receiverNotNull, + callsitePosition = callsitePositions.getOrElse(call, NoPosition), + annotatedInline = inlineAnnotatedCallsites(call), + annotatedNoInline = noInlineAnnotatedCallsites(call) + ) + + case LambdaMetaFactoryCall(indy, samMethodType, implMethod, instantiatedMethodType) if a.frameAt(indy) != null => + val lmf = LambdaMetaFactoryCall(indy, samMethodType, implMethod, instantiatedMethodType) + val capturedArgInfos = computeCapturedArgInfos(lmf, prodCons) + methodClosureInstantiations += indy -> ClosureInstantiation( + lmf, + methodNode, + definingClass, + capturedArgInfos) + + case _ => } - } catch { - case Invalid(noInfo: NoClassBTypeInfo) => - val warning = MethodInlineInfoError(calleeDeclarationClassBType.internalName, calleeMethodNode.name, calleeMethodNode.desc, noInfo) - CallsiteInfo(false, false, false, false, Some(warning)) + + callsites(methodNode) = methodCallsites + closureInstantiations(methodNode) = methodClosureInstantiations } } + } - // TODO: run dataflow analyses to make the call graph more precise - // - producers to get forwarded parameters (ForwardedParam) - // - typeAnalysis for more precise argument types, more precise callee - - // For now we run a NullnessAnalyzer. It is used to determine if the receiver of an instance - // call is known to be not-null, in which case we don't have to emit a null check when inlining. - // It is also used to get the stack height at the call site. - localOpt.minimalRemoveUnreachableCode(methodNode, definingClass.internalName) - - val analyzer: Analyzer[_ <: Value] = { - if (compilerSettings.YoptNullnessTracking) new NullnessAnalyzer - else new Analyzer(new BasicInterpreter) + def computeArgInfos(callee: Either[OptimizerWarning, Callee], callsiteInsn: MethodInsnNode, prodCons: => ProdConsAnalyzer): IntMap[ArgInfo] = { + if (callee.isLeft) IntMap.empty + else { + lazy val numArgs = Type.getArgumentTypes(callsiteInsn.desc).length + (if (callsiteInsn.getOpcode == Opcodes.INVOKESTATIC) 0 else 1) + argInfosForSams(callee.get.samParamTypes, callsiteInsn, numArgs, prodCons) } - analyzer.analyze(definingClass.internalName, methodNode) + } - def receiverNotNullByAnalysis(call: MethodInsnNode, numArgs: Int) = analyzer match { - case nullnessAnalyzer: NullnessAnalyzer => - val frame = nullnessAnalyzer.frameAt(call, methodNode) - frame.getStack(frame.getStackSize - 1 - numArgs).nullness == NotNull + def computeCapturedArgInfos(lmf: LambdaMetaFactoryCall, prodCons: => ProdConsAnalyzer): IntMap[ArgInfo] = { + val capturedSams = capturedSamTypes(lmf) + val numCaptures = Type.getArgumentTypes(lmf.indy.desc).length + argInfosForSams(capturedSams, lmf.indy, numCaptures, prodCons) + } - case _ => false + private def argInfosForSams(sams: IntMap[ClassBType], consumerInsn: AbstractInsnNode, numConsumed: => Int, prodCons: => ProdConsAnalyzer): IntMap[ArgInfo] = { + // TODO: use type analysis instead of ProdCons - should be more efficient + // some random thoughts: + // - assign special types to parameters and indy-lambda-functions to track them + // - upcast should not change type flow analysis: don't lose information. + // - can we do something about factory calls? Foo(x) for case class foo gives a Foo. + // inline the factory? analysis across method boundary? + + // assign to a lazy val to prevent repeated evaluation of the by-name arg + lazy val prodConsI = prodCons + lazy val firstConsumedSlot = { + val consumerFrame = prodConsI.frameAt(consumerInsn) + consumerFrame.stackTop - numConsumed + 1 } - - val callsites = new collection.mutable.ListBuffer[Callsite] - val closureInstantiations = new collection.mutable.ListBuffer[LambdaMetaFactoryCall] - - methodNode.instructions.iterator.asScala foreach { - case call: MethodInsnNode => - val callee: Either[OptimizerWarning, Callee] = for { - (method, declarationClass) <- byteCodeRepository.methodNode(call.owner, call.name, call.desc): Either[OptimizerWarning, (MethodNode, InternalName)] - (declarationClassNode, source) <- byteCodeRepository.classNodeAndSource(declarationClass): Either[OptimizerWarning, (ClassNode, Source)] - declarationClassBType = classBTypeFromClassNode(declarationClassNode) - } yield { - val CallsiteInfo(safeToInline, safeToRewrite, annotatedInline, annotatedNoInline, warning) = analyzeCallsite(method, declarationClassBType, call.owner, source) - Callee( - callee = method, - calleeDeclarationClass = declarationClassBType, - safeToInline = safeToInline, - safeToRewrite = safeToRewrite, - annotatedInline = annotatedInline, - annotatedNoInline = annotatedNoInline, - calleeInfoWarning = warning) + sams flatMap { + case (index, _) => + val prods = prodConsI.initialProducersForValueAt(consumerInsn, firstConsumedSlot + index) + if (prods.size != 1) None + else { + val argInfo = prods.head match { + case LambdaMetaFactoryCall(_, _, _, _) => Some(FunctionLiteral) + case ParameterProducer(local) => Some(ForwardedParam(local)) + case _ => None + } + argInfo.map((index, _)) } + } + } - val argInfos = if (callee.isLeft) Nil else { - // TODO: for now it's Nil, because we don't run any data flow analysis - // there's no point in using the parameter types, that doesn't add any information. - // NOTE: need to run the same analyses after inlining, to re-compute the argInfos for the - // new duplicated callsites, see Inliner.inline - Nil - } + def samParamTypes(methodNode: MethodNode, receiverType: ClassBType): IntMap[ClassBType] = { + val paramTypes = { + val params = Type.getMethodType(methodNode.desc).getArgumentTypes.map(t => bTypeForDescriptorOrInternalNameFromClassfile(t.getDescriptor)) + val isStatic = BytecodeUtils.isStaticMethod(methodNode) + if (isStatic) params else receiverType +: params + } + samTypes(paramTypes) + } - val receiverNotNull = call.getOpcode == Opcodes.INVOKESTATIC || { - val numArgs = Type.getArgumentTypes(call.desc).length - receiverNotNullByAnalysis(call, numArgs) - } + def capturedSamTypes(lmf: LambdaMetaFactoryCall): IntMap[ClassBType] = { + val capturedTypes = Type.getArgumentTypes(lmf.indy.desc).map(t => bTypeForDescriptorOrInternalNameFromClassfile(t.getDescriptor)) + samTypes(capturedTypes) + } - callsites += Callsite( - callsiteInstruction = call, - callsiteMethod = methodNode, - callsiteClass = definingClass, - callee = callee, - argInfos = argInfos, - callsiteStackHeight = analyzer.frameAt(call, methodNode).getStackSize, - receiverKnownNotNull = receiverNotNull, - callsitePosition = callsitePositions.getOrElse(call, NoPosition) - ) - - case LambdaMetaFactoryCall(indy, samMethodType, implMethod, instantiatedMethodType) => - closureInstantiations += LambdaMetaFactoryCall(indy, samMethodType, implMethod, instantiatedMethodType) - - case _ => - } + private def samTypes(types: Array[BType]): IntMap[ClassBType] = { + var res = IntMap.empty[ClassBType] + for (i <- types.indices) { + types(i) match { + case c: ClassBType => + if (c.info.get.inlineInfo.sam.isDefined) res = res.updated(i, c) - (callsites.toList, closureInstantiations.toList) + case _ => + } + } + res } /** + * Just a named tuple used as return type of `analyzeCallsite`. + */ + private case class CallsiteInfo(isStaticallyResolved: Boolean, sourceFilePath: Option[String], + annotatedInline: Boolean, annotatedNoInline: Boolean, + samParamTypes: IntMap[ClassBType], + warning: Option[CalleeInfoWarning]) + + /** + * Analyze a callsite and gather meta-data that can be used for inlining decisions. + */ + private def analyzeCallsite(calleeMethodNode: MethodNode, calleeDeclarationClassBType: ClassBType, call: MethodInsnNode, calleeSourceFilePath: Option[String]): CallsiteInfo = { + val methodSignature = calleeMethodNode.name + calleeMethodNode.desc + + try { + // The inlineInfo.methodInfos of a ClassBType holds an InlineInfo for each method *declared* + // within a class (not for inherited methods). Since we already have the classBType of the + // callee, we only check there for the methodInlineInfo, we should find it there. + calleeDeclarationClassBType.info.orThrow.inlineInfo.methodInfos.get(methodSignature) match { + case Some(methodInlineInfo) => + val isAbstract = BytecodeUtils.isAbstractMethod(calleeMethodNode) + + val receiverType = classBTypeFromParsedClassfile(call.owner) + // (1) A non-final method can be safe to inline if the receiver type is a final subclass. Example: + // class A { @inline def f = 1 }; object B extends A; B.f // can be inlined + // + // TODO: (1) doesn't cover the following example: + // trait TravLike { def map = ... } + // sealed trait List extends TravLike { ... } // assume map is not overridden + // final case class :: / final case object Nil + // (l: List).map // can be inlined + // we need to know that + // - the receiver is sealed + // - what are the children of the receiver + // - all children are final + // - none of the children overrides map + // + // TODO: type analysis can render more calls statically resolved. Example: + // new A.f // can be inlined, the receiver type is known to be exactly A. + val isStaticallyResolved: Boolean = { + isNonVirtualCall(call) || // SD-86: super calls (invokespecial) can be inlined -- TODO: check if that's still needed, and if it's correct: scala-dev#143 + methodInlineInfo.effectivelyFinal || + receiverType.info.orThrow.inlineInfo.isEffectivelyFinal // (1) + } + + val warning = calleeDeclarationClassBType.info.orThrow.inlineInfo.warning.map( + MethodInlineInfoIncomplete(calleeDeclarationClassBType.internalName, calleeMethodNode.name, calleeMethodNode.desc, _)) + + CallsiteInfo( + isStaticallyResolved = isStaticallyResolved, + sourceFilePath = calleeSourceFilePath, + annotatedInline = methodInlineInfo.annotatedInline, + annotatedNoInline = methodInlineInfo.annotatedNoInline, + samParamTypes = samParamTypes(calleeMethodNode, receiverType), + warning = warning) + + case None => + val warning = MethodInlineInfoMissing(calleeDeclarationClassBType.internalName, calleeMethodNode.name, calleeMethodNode.desc, calleeDeclarationClassBType.info.orThrow.inlineInfo.warning) + CallsiteInfo(false, None, false, false, IntMap.empty, Some(warning)) + } + } catch { + case Invalid(noInfo: NoClassBTypeInfo) => + val warning = MethodInlineInfoError(calleeDeclarationClassBType.internalName, calleeMethodNode.name, calleeMethodNode.desc, noInfo) + CallsiteInfo(false, None, false, false, IntMap.empty, Some(warning)) + } + } + + /** * A callsite in the call graph. * * @param callsiteInstruction The invocation instruction @@ -197,21 +335,35 @@ class CallGraph[BT <: BTypes](val btypes: BT) { * @param callsitePosition The source position of the callsite, used for inliner warnings. */ final case class Callsite(callsiteInstruction: MethodInsnNode, callsiteMethod: MethodNode, callsiteClass: ClassBType, - callee: Either[OptimizerWarning, Callee], argInfos: List[ArgInfo], - callsiteStackHeight: Int, receiverKnownNotNull: Boolean, callsitePosition: Position) { + callee: Either[OptimizerWarning, Callee], argInfos: IntMap[ArgInfo], + callsiteStackHeight: Int, receiverKnownNotNull: Boolean, callsitePosition: Position, + annotatedInline: Boolean, annotatedNoInline: Boolean) { + /** + * Contains callsites that were created during inlining by cloning this callsite. Used to find + * corresponding callsites when inlining post-inline requests. + */ + val inlinedClones = mutable.Set.empty[ClonedCallsite] + + // an annotation at the callsite takes precedence over an annotation at the definition site + def isInlineAnnotated = annotatedInline || (callee.get.annotatedInline && !annotatedNoInline) + def isNoInlineAnnotated = annotatedNoInline || (callee.get.annotatedNoInline && !annotatedInline) + override def toString = "Invocation of" + s" ${callee.map(_.calleeDeclarationClass.internalName).getOrElse("?")}.${callsiteInstruction.name + callsiteInstruction.desc}" + s"@${callsiteMethod.instructions.indexOf(callsiteInstruction)}" + - s" in ${callsiteClass.internalName}.${callsiteMethod.name}" + s" in ${callsiteClass.internalName}.${callsiteMethod.name}${callsiteMethod.desc}" } + final case class ClonedCallsite(callsite: Callsite, clonedWhenInlining: Callsite) + /** * Information about invocation arguments, obtained through data flow analysis of the callsite method. */ sealed trait ArgInfo - final case class ArgTypeInfo(argType: BType, isPrecise: Boolean, knownNotNull: Boolean) extends ArgInfo + case object FunctionLiteral extends ArgInfo final case class ForwardedParam(index: Int) extends ArgInfo + // final case class ArgTypeInfo(argType: BType, isPrecise: Boolean, knownNotNull: Boolean) extends ArgInfo // can be extended, e.g., with constant types /** @@ -221,46 +373,50 @@ class CallGraph[BT <: BTypes](val btypes: BT) { * virtual calls, an override of the callee might be invoked. Also, * the callee can be abstract. * @param calleeDeclarationClass The class in which the callee is declared - * @param safeToInline True if the callee can be safely inlined: it cannot be overridden, - * and the inliner settings (project / global) allow inlining it. - * @param safeToRewrite True if the callee is the interface method of a concrete trait method - * that can be safely re-written to the static implementation method. + * @param isStaticallyResolved True if the callee cannot be overridden * @param annotatedInline True if the callee is annotated @inline * @param annotatedNoInline True if the callee is annotated @noinline + * @param samParamTypes A map from parameter positions to SAM parameter types * @param calleeInfoWarning An inliner warning if some information was not available while * gathering the information about this callee. */ - final case class Callee(callee: MethodNode, calleeDeclarationClass: ClassBType, - safeToInline: Boolean, safeToRewrite: Boolean, + final case class Callee(callee: MethodNode, calleeDeclarationClass: btypes.ClassBType, + isStaticallyResolved: Boolean, sourceFilePath: Option[String], annotatedInline: Boolean, annotatedNoInline: Boolean, + samParamTypes: IntMap[btypes.ClassBType], calleeInfoWarning: Option[CalleeInfoWarning]) { - assert(!(safeToInline && safeToRewrite), s"A callee of ${callee.name} can be either safeToInline or safeToRewrite, but not both.") + override def toString = s"Callee($calleeDeclarationClass.${callee.name})" + + def canInlineFromSource = inlinerHeuristics.canInlineFromSource(sourceFilePath) + def isAbstract = isAbstractMethod(callee) + def isSpecialMethod = isConstructor(callee) || isNativeMethod(callee) || hasCallerSensitiveAnnotation(callee) + + def safeToInline = isStaticallyResolved && canInlineFromSource && !isAbstract && !isSpecialMethod } - final case class ClosureInstantiation(lambdaMetaFactoryCall: LambdaMetaFactoryCall, ownerMethod: MethodNode, ownerClass: ClassBType) { + /** + * Metadata about a closure instantiation, stored in the call graph + * + * @param lambdaMetaFactoryCall the InvokeDynamic instruction + * @param ownerMethod the method where the closure is allocated + * @param ownerClass the class containing the above method + * @param capturedArgInfos information about captured arguments. Used for updating the call + * graph when re-writing a closure invocation to the body method. + */ + final case class ClosureInstantiation(lambdaMetaFactoryCall: LambdaMetaFactoryCall, ownerMethod: MethodNode, ownerClass: ClassBType, capturedArgInfos: IntMap[ArgInfo]) { + /** + * Contains closure instantiations that were created during inlining by cloning this instantiation. + */ + val inlinedClones = mutable.Set.empty[ClosureInstantiation] override def toString = s"ClosureInstantiation($lambdaMetaFactoryCall, ${ownerMethod.name + ownerMethod.desc}, $ownerClass)" } final case class LambdaMetaFactoryCall(indy: InvokeDynamicInsnNode, samMethodType: Type, implMethod: Handle, instantiatedMethodType: Type) object LambdaMetaFactoryCall { - private val lambdaMetaFactoryInternalName: InternalName = "java/lang/invoke/LambdaMetafactory" - - private val metafactoryHandle = { - val metafactoryMethodName: String = "metafactory" - val metafactoryDesc: String = "(Ljava/lang/invoke/MethodHandles$Lookup;Ljava/lang/String;Ljava/lang/invoke/MethodType;Ljava/lang/invoke/MethodType;Ljava/lang/invoke/MethodHandle;Ljava/lang/invoke/MethodType;)Ljava/lang/invoke/CallSite;" - new Handle(Opcodes.H_INVOKESTATIC, lambdaMetaFactoryInternalName, metafactoryMethodName, metafactoryDesc) - } - - private val altMetafactoryHandle = { - val altMetafactoryMethodName: String = "altMetafactory" - val altMetafactoryDesc: String = "(Ljava/lang/invoke/MethodHandles$Lookup;Ljava/lang/String;Ljava/lang/invoke/MethodType;[Ljava/lang/Object;)Ljava/lang/invoke/CallSite;" - new Handle(Opcodes.H_INVOKESTATIC, lambdaMetaFactoryInternalName, altMetafactoryMethodName, altMetafactoryDesc) - } - def unapply(insn: AbstractInsnNode): Option[(InvokeDynamicInsnNode, Type, Handle, Type)] = insn match { - case indy: InvokeDynamicInsnNode if indy.bsm == metafactoryHandle || indy.bsm == altMetafactoryHandle => + case indy: InvokeDynamicInsnNode if indy.bsm == coreBTypes.lambdaMetaFactoryMetafactoryHandle || indy.bsm == coreBTypes.lambdaMetaFactoryAltMetafactoryHandle => indy.bsmArgs match { - case Array(samMethodType: Type, implMethod: Handle, instantiatedMethodType: Type, xs@_*) => // xs binding because IntelliJ gets confused about _@_* + case Array(samMethodType: Type, implMethod: Handle, instantiatedMethodType: Type, _@_*) => // LambdaMetaFactory performs a number of automatic adaptations when invoking the lambda // implementation method (casting, boxing, unboxing, and primitive widening, see Javadoc). // @@ -284,7 +440,7 @@ class CallGraph[BT <: BTypes](val btypes: BT) { // When re-writing the closure callsite to the implMethod, we have to insert a cast. // // The check below ensures that - // (1) the implMethod type has the expected singature (captured types plus argument types + // (1) the implMethod type has the expected signature (captured types plus argument types // from instantiatedMethodType) // (2) the receiver of the implMethod matches the first captured type // (3) all parameters that are not the same in samMethodType and instantiatedMethodType diff --git a/src/compiler/scala/tools/nsc/backend/jvm/opt/ClosureOptimizer.scala b/src/compiler/scala/tools/nsc/backend/jvm/opt/ClosureOptimizer.scala index b0dc6ead1b..2fca8991ab 100644 --- a/src/compiler/scala/tools/nsc/backend/jvm/opt/ClosureOptimizer.scala +++ b/src/compiler/scala/tools/nsc/backend/jvm/opt/ClosureOptimizer.scala @@ -8,21 +8,39 @@ package backend.jvm package opt import scala.annotation.switch -import scala.collection.immutable +import scala.collection.mutable +import scala.collection.immutable.IntMap import scala.reflect.internal.util.NoPosition import scala.tools.asm.{Type, Opcodes} import scala.tools.asm.tree._ import scala.tools.nsc.backend.jvm.BTypes.InternalName -import scala.tools.nsc.backend.jvm.analysis.ProdConsAnalyzer import BytecodeUtils._ import BackendReporting._ import Opcodes._ -import scala.tools.nsc.backend.jvm.opt.ByteCodeRepository.CompilationUnit -import scala.collection.convert.decorateAsScala._ +import scala.collection.JavaConverters._ class ClosureOptimizer[BT <: BTypes](val btypes: BT) { import btypes._ import callGraph._ + import coreBTypes._ + import backendUtils._ + import ClosureOptimizer._ + + private object closureInitOrdering extends Ordering[ClosureInstantiation] { + override def compare(x: ClosureInstantiation, y: ClosureInstantiation): Int = { + val cls = x.ownerClass.internalName compareTo y.ownerClass.internalName + if (cls != 0) return cls + + val mName = x.ownerMethod.name compareTo y.ownerMethod.name + if (mName != 0) return mName + + val mDesc = x.ownerMethod.desc compareTo y.ownerMethod.desc + if (mDesc != 0) return mDesc + + def pos(inst: ClosureInstantiation) = inst.ownerMethod.instructions.indexOf(inst.lambdaMetaFactoryCall.indy) + pos(x) - pos(y) + } + } /** * If a closure is allocated and invoked within the same method, re-write the invocation to the @@ -54,55 +72,51 @@ class ClosureOptimizer[BT <: BTypes](val btypes: BT) { * [invoke the closure body method] */ def rewriteClosureApplyInvocations(): Unit = { - implicit object closureInitOrdering extends Ordering[ClosureInstantiation] { - override def compare(x: ClosureInstantiation, y: ClosureInstantiation): Int = { - val cls = x.ownerClass.internalName compareTo y.ownerClass.internalName - if (cls != 0) return cls - - val mName = x.ownerMethod.name compareTo y.ownerMethod.name - if (mName != 0) return mName - val mDesc = x.ownerMethod.desc compareTo y.ownerMethod.desc - if (mDesc != 0) return mDesc - - def pos(inst: ClosureInstantiation) = inst.ownerMethod.instructions.indexOf(inst.lambdaMetaFactoryCall.indy) - pos(x) - pos(y) - } + // sort all closure invocations to rewrite to ensure bytecode stability + val toRewrite = mutable.TreeMap.empty[ClosureInstantiation, mutable.ArrayBuffer[(MethodInsnNode, Int)]](closureInitOrdering) + def addRewrite(init: ClosureInstantiation, invocation: MethodInsnNode, stackHeight: Int): Unit = { + val callsites = toRewrite.getOrElseUpdate(init, mutable.ArrayBuffer.empty[(MethodInsnNode, Int)]) + callsites += ((invocation, stackHeight)) } - // Grouping the closure instantiations by method allows running the ProdConsAnalyzer only once per - // method. Also sort the instantiations: If there are multiple closure instantiations in a method, - // closure invocations need to be re-written in a consistent order for bytecode stability. The local - // variable slots for storing captured values depends on the order of rewriting. - val closureInstantiationsByMethod: Map[MethodNode, immutable.TreeSet[ClosureInstantiation]] = { - closureInstantiations.values.groupBy(_.ownerMethod).mapValues(immutable.TreeSet.empty ++ _) - } + // For each closure instantiation find callsites of the closure and add them to the toRewrite + // buffer (cannot change a method's bytecode while still looking for further invocations to + // rewrite, the frame indices of the ProdCons analysis would get out of date). If a callsite + // cannot be rewritten, for example because the lambda body method is not accessible, issue a + // warning. The `toList` in the next line prevents modifying closureInstantiations while + // iterating it: minimalRemoveUnreachableCode (called in the loop) removes elements. + for (method <- closureInstantiations.keysIterator.toList if AsmAnalyzer.sizeOKForBasicValue(method)) closureInstantiations.get(method) match { + case Some(closureInitsBeforeDCE) if closureInitsBeforeDCE.nonEmpty => + val ownerClass = closureInitsBeforeDCE.head._2.ownerClass.internalName + + // Advanced ProdCons queries (initialProducersForValueAt) expect no unreachable code. + localOpt.minimalRemoveUnreachableCode(method, ownerClass) + + if (AsmAnalyzer.sizeOKForSourceValue(method)) closureInstantiations.get(method) match { + case Some(closureInits) => + // A lazy val to ensure the analysis only runs if necessary (the value is passed by name to `closureCallsites`) + lazy val prodCons = new ProdConsAnalyzer(method, ownerClass) + + for (init <- closureInits.valuesIterator) closureCallsites(init, prodCons) foreach { + case Left(warning) => + backendReporting.inlinerWarning(warning.pos, warning.toString) + + case Right((invocation, stackHeight)) => + addRewrite(init, invocation, stackHeight) + } + + case _ => + } - // For each closure instantiation, a list of callsites of the closure that can be re-written - // If a callsite cannot be rewritten, for example because the lambda body method is not accessible, - // a warning is returned instead. - val callsitesToRewrite: List[(ClosureInstantiation, List[Either[RewriteClosureApplyToClosureBodyFailed, (MethodInsnNode, Int)]])] = { - closureInstantiationsByMethod.iterator.flatMap({ - case (methodNode, closureInits) => - // A lazy val to ensure the analysis only runs if necessary (the value is passed by name to `closureCallsites`) - lazy val prodCons = new ProdConsAnalyzer(methodNode, closureInits.head.ownerClass.internalName) - closureInits.iterator.map(init => (init, closureCallsites(init, prodCons))) - }).toList // mapping to a list (not a map) to keep the sorting of closureInstantiationsByMethod + case _ => } - // Rewrite all closure callsites (or issue inliner warnings for those that cannot be rewritten) - for ((closureInit, callsites) <- callsitesToRewrite) { + for ((closureInit, invocations) <- toRewrite) { // Local variables that hold the captured values and the closure invocation arguments. - // They are lazy vals to ensure that locals for captured values are only allocated if there's - // actually a callsite to rewrite (an not only warnings to be issued). - lazy val (localsForCapturedValues, argumentLocalsList) = localsForClosureRewrite(closureInit) - for (callsite <- callsites) callsite match { - case Left(warning) => - backendReporting.inlinerWarning(warning.pos, warning.toString) - - case Right((invocation, stackHeight)) => - rewriteClosureApplyInvocation(closureInit, invocation, stackHeight, localsForCapturedValues, argumentLocalsList) - } + val (localsForCapturedValues, argumentLocalsList) = localsForClosureRewrite(closureInit) + for ((invocation, stackHeight) <- invocations) + rewriteClosureApplyInvocation(closureInit, invocation, stackHeight, localsForCapturedValues, argumentLocalsList) } } @@ -122,20 +136,7 @@ class ClosureOptimizer[BT <: BTypes](val btypes: BT) { val argTypes = closureInit.lambdaMetaFactoryCall.samMethodType.getArgumentTypes val firstArgLocal = ownerMethod.maxLocals - // The comment in the unapply method of `LambdaMetaFactoryCall` explains why we have to introduce - // casts for arguments that have different types in samMethodType and instantiatedMethodType. - val castLoadTypes = { - val instantiatedMethodType = closureInit.lambdaMetaFactoryCall.instantiatedMethodType - (argTypes, instantiatedMethodType.getArgumentTypes).zipped map { - case (samArgType, instantiatedArgType) if samArgType != instantiatedArgType => - // the LambdaMetaFactoryCall extractor ensures that the two types are reference types, - // so we don't end up casting primitive values. - Some(instantiatedArgType) - case _ => - None - } - } - val argLocals = LocalsList.fromTypes(firstArgLocal, argTypes, castLoadTypes) + val argLocals = LocalsList.fromTypes(firstArgLocal, argTypes) ownerMethod.maxLocals = firstArgLocal + argLocals.size (captureLocals, argLocals) @@ -154,7 +155,7 @@ class ClosureOptimizer[BT <: BTypes](val btypes: BT) { // TODO: This is maybe over-cautious. // We are checking if the closure body method is accessible at the closure callsite. // If the closure allocation has access to the body method, then the callsite (in the same - // method as the alloction) should have access too. + // method as the allocation) should have access too. val bodyAccessible: Either[OptimizerWarning, Boolean] = for { (bodyMethodNode, declClass) <- byteCodeRepository.methodNode(lambdaBodyHandle.getOwner, lambdaBodyHandle.getName, lambdaBodyHandle.getDesc): Either[OptimizerWarning, (MethodNode, InternalName)] isAccessible <- inliner.memberIsAccessible(bodyMethodNode.access, classBTypeFromParsedClassfile(declClass), classBTypeFromParsedClassfile(lambdaBodyHandle.getOwner), ownerClass) @@ -162,7 +163,7 @@ class ClosureOptimizer[BT <: BTypes](val btypes: BT) { isAccessible } - def pos = callGraph.callsites.get(invocation).map(_.callsitePosition).getOrElse(NoPosition) + def pos = callGraph.callsites(ownerMethod).get(invocation).map(_.callsitePosition).getOrElse(NoPosition) val stackSize: Either[RewriteClosureApplyToClosureBodyFailed, Int] = bodyAccessible match { case Left(w) => Left(RewriteClosureAccessCheckFailed(pos, w)) case Right(false) => Left(RewriteClosureIllegalAccess(pos, ownerClass.internalName)) @@ -173,6 +174,28 @@ class ClosureOptimizer[BT <: BTypes](val btypes: BT) { }).toList } + /** + * Check whether `invocation` invokes the SAM of the IndyLambda `closureInit`. + * + * In addition to a perfect match, we also identify cases where a generic FunctionN is created + * but the invocation is to a specialized variant apply$sp... Vice-versa, we also allow the + * case where a specialized FunctionN$sp.. is created but the generic apply is invoked. In + * these cases, the translation will introduce the necessary box / unbox invocations. Example: + * + * val f: Int => Any = (x: Int) => 1 + * f(10) + * + * The IndyLambda creates a specialized `JFunction1$mcII$sp`, whose SAM is `apply$mcII$sp(I)I`. + * The invocation calls `apply(Object)Object`: the method name and type don't match. + * We identify these cases, insert the necessary unbox operation for the arguments, and invoke + * the `$anonfun(I)I` method. + * + * Tests in InlinerTest.optimizeSpecializedClosures. In that test, methods t4/t4a/t5/t8 show + * examples where the parameters have to be unboxed because generic `apply` is called, but the + * lambda body method takes primitive types. + * The opposite case is in t9: a the specialized `apply$sp..` is invoked, but the lambda body + * method takes boxed arguments, so we have to insert boxing operations. + */ private def isSamInvocation(invocation: MethodInsnNode, closureInit: ClosureInstantiation, prodCons: => ProdConsAnalyzer): Boolean = { val indy = closureInit.lambdaMetaFactoryCall.indy if (invocation.getOpcode == INVOKESTATIC) false @@ -187,11 +210,85 @@ class ClosureOptimizer[BT <: BTypes](val btypes: BT) { receiverProducers.size == 1 && receiverProducers.head == indy } - invocation.name == indy.name && { - val indySamMethodDesc = closureInit.lambdaMetaFactoryCall.samMethodType.getDescriptor - indySamMethodDesc == invocation.desc - } && - closureIsReceiver // most expensive check last + def isSpecializedVersion(specName: String, nonSpecName: String) = specName.startsWith(nonSpecName) && specializationSuffix.pattern.matcher(specName.substring(nonSpecName.length)).matches + + def sameOrSpecializedType(specTp: Type, nonSpecTp: Type) = { + specTp == nonSpecTp || { + val specDesc = specTp.getDescriptor + val nonSpecDesc = nonSpecTp.getDescriptor + specDesc.length == 1 && primitives.contains(specDesc) && nonSpecDesc == ObjectRef.descriptor + } + } + + def specializedDescMatches(specMethodDesc: String, nonSpecMethodDesc: String) = { + val specArgs = Type.getArgumentTypes(specMethodDesc) + val nonSpecArgs = Type.getArgumentTypes(nonSpecMethodDesc) + specArgs.corresponds(nonSpecArgs)(sameOrSpecializedType) && sameOrSpecializedType(Type.getReturnType(specMethodDesc), Type.getReturnType(nonSpecMethodDesc)) + } + + def nameAndDescMatch = { + val aName = invocation.name + val bName = indy.name + val aDesc = invocation.desc + val bDesc = closureInit.lambdaMetaFactoryCall.samMethodType.getDescriptor + if (aName == bName) aDesc == bDesc + else if (isSpecializedVersion(aName, bName)) specializedDescMatches(aDesc, bDesc) + else if (isSpecializedVersion(bName, aName)) specializedDescMatches(bDesc, aDesc) + else false + } + + nameAndDescMatch && closureIsReceiver // most expensive check last + } + } + + private def isPrimitiveType(asmType: Type) = { + val sort = asmType.getSort + Type.VOID <= sort && sort <= Type.DOUBLE + } + + /** + * The argument types of the lambda body method may differ in two ways from the argument types of + * the closure member method that is invoked (and replaced by a call to the body). + * - The lambda body method may have more specific types than the invoked closure member, see + * comment in [[LambdaMetaFactoryCall.unapply]]. + * - The invoked closure member might be a specialized variant of the SAM or vice-versa, see + * comment method [[isSamInvocation]]. + */ + private def adaptStoredArguments(closureInit: ClosureInstantiation, invocation: MethodInsnNode): Int => Option[AbstractInsnNode] = { + val invokeDesc = invocation.desc + // The lambda body method has additional parameters for captured values. Here we need to consider + // only those parameters of the body method that correspond to lambda parameters. This happens + // to be exactly LMF.instantiatedMethodType. In fact, `LambdaMetaFactoryCall.unapply` ensures + // that the body method signature is exactly (capturedParams + instantiatedMethodType). + val lambdaBodyMethodDescWithoutCaptures = closureInit.lambdaMetaFactoryCall.instantiatedMethodType.getDescriptor + if (invokeDesc == lambdaBodyMethodDescWithoutCaptures) { + _ => None + } else { + val invokeArgTypes = Type.getArgumentTypes(invokeDesc) + val implMethodArgTypes = Type.getArgumentTypes(lambdaBodyMethodDescWithoutCaptures) + val res = new Array[Option[AbstractInsnNode]](invokeArgTypes.length) + for (i <- invokeArgTypes.indices) { + if (invokeArgTypes(i) == implMethodArgTypes(i)) { + res(i) = None + } else if (isPrimitiveType(implMethodArgTypes(i)) && invokeArgTypes(i).getDescriptor == ObjectRef.descriptor) { + res(i) = Some(getScalaUnbox(implMethodArgTypes(i))) + } else if (isPrimitiveType(invokeArgTypes(i)) && implMethodArgTypes(i).getDescriptor == ObjectRef.descriptor) { + res(i) = Some(getScalaBox(invokeArgTypes(i))) + } else { + assert(!isPrimitiveType(invokeArgTypes(i)), invokeArgTypes(i)) + assert(!isPrimitiveType(implMethodArgTypes(i)), implMethodArgTypes(i)) + // The comment in the unapply method of `LambdaMetaFactoryCall` explains why we have to introduce + // casts for arguments that have different types in samMethodType and instantiatedMethodType. + // + // Note: + // - invokeArgTypes is the same as the argument types in the IndyLambda's samMethodType, + // this is ensured by the `isSamInvocation` filter in this file + // - implMethodArgTypes is the same as the arg types in the IndyLambda's instantiatedMethodType, + // this is ensured by the unapply method in LambdaMetaFactoryCall (file CallGraph) + res(i) = Some(new TypeInsnNode(CHECKCAST, implMethodArgTypes(i).getInternalName)) + } + } + res } } @@ -200,7 +297,7 @@ class ClosureOptimizer[BT <: BTypes](val btypes: BT) { val lambdaBodyHandle = closureInit.lambdaMetaFactoryCall.implMethod // store arguments - insertStoreOps(invocation, ownerMethod, argumentLocalsList) + insertStoreOps(invocation, ownerMethod, argumentLocalsList, adaptStoredArguments(closureInit, invocation)) // drop the closure from the stack ownerMethod.instructions.insertBefore(invocation, new InsnNode(POP)) @@ -210,8 +307,9 @@ class ClosureOptimizer[BT <: BTypes](val btypes: BT) { insertLoadOps(invocation, ownerMethod, argumentLocalsList) // update maxStack - val capturesStackSize = localsForCapturedValues.size - val invocationStackHeight = stackHeight + capturesStackSize - 1 // -1 because the closure is gone + // One slot per value is correct for long / double, see comment in the `analysis` package object. + val numCapturedValues = localsForCapturedValues.locals.length + val invocationStackHeight = stackHeight + numCapturedValues - 1 // -1 because the closure is gone if (invocationStackHeight > ownerMethod.maxStack) ownerMethod.maxStack = invocationStackHeight @@ -227,46 +325,75 @@ class ClosureOptimizer[BT <: BTypes](val btypes: BT) { insns.insertBefore(invocation, new InsnNode(DUP)) INVOKESPECIAL } - val isInterface = bodyOpcode == INVOKEINTERFACE - val bodyInvocation = new MethodInsnNode(bodyOpcode, lambdaBodyHandle.getOwner, lambdaBodyHandle.getName, lambdaBodyHandle.getDesc, isInterface) + val bodyInvocation = new MethodInsnNode(bodyOpcode, lambdaBodyHandle.getOwner, lambdaBodyHandle.getName, lambdaBodyHandle.getDesc, lambdaBodyHandle.isInterface) ownerMethod.instructions.insertBefore(invocation, bodyInvocation) - val returnType = Type.getReturnType(lambdaBodyHandle.getDesc) - fixLoadedNothingOrNullValue(returnType, bodyInvocation, ownerMethod, btypes) // see comment of that method + val bodyReturnType = Type.getReturnType(lambdaBodyHandle.getDesc) + val invocationReturnType = Type.getReturnType(invocation.desc) + if (isPrimitiveType(invocationReturnType) && bodyReturnType.getDescriptor == ObjectRef.descriptor) { + val op = + if (invocationReturnType.getSort == Type.VOID) getPop(1) + else getScalaUnbox(invocationReturnType) + ownerMethod.instructions.insertBefore(invocation, op) + } else if (isPrimitiveType(bodyReturnType) && invocationReturnType.getDescriptor == ObjectRef.descriptor) { + val op = + if (bodyReturnType.getSort == Type.VOID) getBoxedUnit + else getScalaBox(bodyReturnType) + ownerMethod.instructions.insertBefore(invocation, op) + } else { + // see comment of that method + fixLoadedNothingOrNullValue(bodyReturnType, bodyInvocation, ownerMethod, btypes) + } ownerMethod.instructions.remove(invocation) // update the call graph - val originalCallsite = callGraph.callsites.remove(invocation) + val originalCallsite = callGraph.removeCallsite(invocation, ownerMethod) // the method node is needed for building the call graph entry val bodyMethod = byteCodeRepository.methodNode(lambdaBodyHandle.getOwner, lambdaBodyHandle.getName, lambdaBodyHandle.getDesc) - def bodyMethodIsBeingCompiled = byteCodeRepository.classNodeAndSource(lambdaBodyHandle.getOwner).map(_._2 == CompilationUnit).getOrElse(false) - val bodyMethodCallsite = Callsite( - callsiteInstruction = bodyInvocation, - callsiteMethod = ownerMethod, - callsiteClass = closureInit.ownerClass, - callee = bodyMethod.map({ - case (bodyMethodNode, bodyMethodDeclClass) => Callee( + val sourceFilePath = byteCodeRepository.compilingClasses.get(lambdaBodyHandle.getOwner).map(_._2) + val callee = bodyMethod.map({ + case (bodyMethodNode, bodyMethodDeclClass) => + val bodyDeclClassType = classBTypeFromParsedClassfile(bodyMethodDeclClass) + Callee( callee = bodyMethodNode, - calleeDeclarationClass = classBTypeFromParsedClassfile(bodyMethodDeclClass), - safeToInline = compilerSettings.YoptInlineGlobal || bodyMethodIsBeingCompiled, - safeToRewrite = false, // the lambda body method is not a trait interface method + calleeDeclarationClass = bodyDeclClassType, + isStaticallyResolved = true, + sourceFilePath = sourceFilePath, annotatedInline = false, annotatedNoInline = false, + samParamTypes = callGraph.samParamTypes(bodyMethodNode, bodyDeclClassType), calleeInfoWarning = None) - }), - argInfos = Nil, + }) + val argInfos = closureInit.capturedArgInfos ++ originalCallsite.map(cs => cs.argInfos map { + case (index, info) => (index + numCapturedValues, info) + }).getOrElse(IntMap.empty) + val bodyMethodCallsite = Callsite( + callsiteInstruction = bodyInvocation, + callsiteMethod = ownerMethod, + callsiteClass = closureInit.ownerClass, + callee = callee, + argInfos = argInfos, callsiteStackHeight = invocationStackHeight, receiverKnownNotNull = true, // see below (*) - callsitePosition = originalCallsite.map(_.callsitePosition).getOrElse(NoPosition) + callsitePosition = originalCallsite.map(_.callsitePosition).getOrElse(NoPosition), + annotatedInline = false, + annotatedNoInline = false ) // (*) The documentation in class LambdaMetafactory says: // "if implMethod corresponds to an instance method, the first capture argument // (corresponding to the receiver) must be non-null" // Explanation: If the lambda body method is non-static, the receiver is a captured // value. It can only be captured within some instance method, so we know it's non-null. - callGraph.callsites(bodyInvocation) = bodyMethodCallsite + callGraph.addCallsite(bodyMethodCallsite) + + // Rewriting a closure invocation may render code unreachable. For example, the body method of + // (x: T) => ??? has return type Nothing$, and an ATHROW is added (see fixLoadedNothingOrNullValue). + unreachableCodeEliminated -= ownerMethod + + if (hasAdaptedImplMethod(closureInit) && inliner.canInlineCallsite(bodyMethodCallsite).isEmpty) + inliner.inlineCallsite(bodyMethodCallsite) } /** @@ -283,13 +410,10 @@ class ClosureOptimizer[BT <: BTypes](val btypes: BT) { // local. On the other hand, further optimizations (copy propagation, remove unused locals) will // clean it up. - // Captured variables don't need to be cast when loaded at the callsite (castLoadTypes are None). - // This is checked in `isClosureInstantiation`: the types of the captured variables in the indy - // instruction match exactly the corresponding parameter types in the body method. - val localsForCaptures = LocalsList.fromTypes(firstCaptureLocal, capturedTypes, castLoadTypes = _ => None) + val localsForCaptures = LocalsList.fromTypes(firstCaptureLocal, capturedTypes) closureInit.ownerMethod.maxLocals = firstCaptureLocal + localsForCaptures.size - insertStoreOps(indy, closureInit.ownerMethod, localsForCaptures) + insertStoreOps(indy, closureInit.ownerMethod, localsForCaptures, _ => None) insertLoadOps(indy, closureInit.ownerMethod, localsForCaptures) localsForCaptures @@ -301,8 +425,16 @@ class ClosureOptimizer[BT <: BTypes](val btypes: BT) { * * The lowest stack value is stored in the head of the locals list, so the last local is stored first. */ - private def insertStoreOps(before: AbstractInsnNode, methodNode: MethodNode, localsList: LocalsList) = - insertLocalValueOps(before, methodNode, localsList, store = true) + private def insertStoreOps(before: AbstractInsnNode, methodNode: MethodNode, localsList: LocalsList, beforeStore: Int => Option[AbstractInsnNode]) = { + // The first instruction needs to store into the last local of the `localsList`. + // To avoid reversing the list, we use `insert(previous)`. + val previous = before.getPrevious + def ins(op: AbstractInsnNode) = methodNode.instructions.insert(previous, op) + for ((l, i) <- localsList.locals.zipWithIndex) { + ins(new VarInsnNode(l.storeOpcode, l.local)) + beforeStore(i) foreach ins + } + } /** * Insert load operations in front of the `before` instruction to copy the local values denoted @@ -310,20 +442,10 @@ class ClosureOptimizer[BT <: BTypes](val btypes: BT) { * * The head of the locals list will be the lowest value on the stack, so the first local is loaded first. */ - private def insertLoadOps(before: AbstractInsnNode, methodNode: MethodNode, localsList: LocalsList) = - insertLocalValueOps(before, methodNode, localsList, store = false) - - private def insertLocalValueOps(before: AbstractInsnNode, methodNode: MethodNode, localsList: LocalsList, store: Boolean): Unit = { - // If `store` is true, the first instruction needs to store into the last local of the `localsList`. - // Load instructions on the other hand are emitted in the order of the list. - // To avoid reversing the list, we use `insert(previousInstr)` for stores and `insertBefore(before)` for loads. - lazy val previous = before.getPrevious + private def insertLoadOps(before: AbstractInsnNode, methodNode: MethodNode, localsList: LocalsList) = { for (l <- localsList.locals) { - val varOp = new VarInsnNode(if (store) l.storeOpcode else l.loadOpcode, l.local) - if (store) methodNode.instructions.insert(previous, varOp) - else methodNode.instructions.insertBefore(before, varOp) - if (!store) for (castType <- l.castLoadedValue) - methodNode.instructions.insert(varOp, new TypeInsnNode(CHECKCAST, castType.getInternalName)) + val op = new VarInsnNode(l.loadOpcode, l.local) + methodNode.instructions.insertBefore(before, op) } } @@ -345,12 +467,12 @@ class ClosureOptimizer[BT <: BTypes](val btypes: BT) { * Local(6, refOpOffset) :: * Nil */ - def fromTypes(firstLocal: Int, types: Array[Type], castLoadTypes: Int => Option[Type]): LocalsList = { + def fromTypes(firstLocal: Int, types: Array[Type]): LocalsList = { var sizeTwoOffset = 0 val locals: List[Local] = types.indices.map(i => { // The ASM method `type.getOpcode` returns the opcode for operating on a value of `type`. val offset = types(i).getOpcode(ILOAD) - ILOAD - val local = Local(firstLocal + i + sizeTwoOffset, offset, castLoadTypes(i)) + val local = Local(firstLocal + i + sizeTwoOffset, offset) if (local.size == 2) sizeTwoOffset += 1 local })(collection.breakOut) @@ -364,10 +486,15 @@ class ClosureOptimizer[BT <: BTypes](val btypes: BT) { * The xLOAD / xSTORE opcodes are in the following sequence: I, L, F, D, A, so the offset for * a local variable holding a reference (`A`) is 4. See also method `getOpcode` in [[scala.tools.asm.Type]]. */ - case class Local(local: Int, opcodeOffset: Int, castLoadedValue: Option[Type]) { + case class Local(local: Int, opcodeOffset: Int) { def size = if (loadOpcode == LLOAD || loadOpcode == DLOAD) 2 else 1 def loadOpcode = ILOAD + opcodeOffset def storeOpcode = ISTORE + opcodeOffset } } + +object ClosureOptimizer { + val primitives = "BSIJCFDZV" + val specializationSuffix = s"(\\$$mc[$primitives]+\\$$sp)".r +} diff --git a/src/compiler/scala/tools/nsc/backend/jvm/opt/CopyProp.scala b/src/compiler/scala/tools/nsc/backend/jvm/opt/CopyProp.scala new file mode 100644 index 0000000000..518646812e --- /dev/null +++ b/src/compiler/scala/tools/nsc/backend/jvm/opt/CopyProp.scala @@ -0,0 +1,635 @@ +/* NSC -- new Scala compiler + * Copyright 2005-2014 LAMP/EPFL + * @author Martin Odersky + */ + +package scala.tools.nsc +package backend.jvm +package opt + +import scala.annotation.{switch, tailrec} +import scala.tools.asm.tree.analysis.BasicInterpreter +import scala.tools.asm.Type +import scala.tools.asm.Opcodes._ +import scala.tools.asm.tree._ +import scala.collection.mutable +import scala.collection.JavaConverters._ +import scala.tools.nsc.backend.jvm.BTypes.InternalName +import scala.tools.nsc.backend.jvm.analysis._ +import scala.tools.nsc.backend.jvm.opt.BytecodeUtils._ + +class CopyProp[BT <: BTypes](val btypes: BT) { + import btypes._ + import backendUtils._ + + + /** + * For every `xLOAD n`, find all local variable slots that are aliases of `n` using an + * AliasingAnalyzer and change the instruction to `xLOAD m` where `m` is the smallest alias. + * This leaves behind potentially stale `xSTORE n` instructions, which are then eliminated + * by [[eliminateStaleStores]]. + */ + def copyPropagation(method: MethodNode, owner: InternalName): Boolean = { + AsmAnalyzer.sizeOKForAliasing(method) && { + var changed = false + val numParams = parametersSize(method) + lazy val aliasAnalysis = new AsmAnalyzer(method, owner, new AliasingAnalyzer(new BasicInterpreter)) + + // Remember locals that are used in a `LOAD` instruction. Assume a program has two LOADs: + // + // ... + // LOAD 3 // aliases of 3 here: <3> + // ... + // LOAD 1 // aliases of 1 here: <1, 3> + // + // In this example, we should change the second load from 1 to 3, which might render the + // local variable 1 unused. + val knownUsed = new Array[Boolean](method.maxLocals) + + def usedOrMinAlias(it: IntIterator, init: Int): Int = { + if (knownUsed(init)) init + else { + var r = init + while (it.hasNext) { + val n = it.next() + // knownUsed.length is the number of locals, `n` may be a stack slot + if (n < knownUsed.length && knownUsed(n)) return n + if (n < r) r = n + } + r + } + } + + val it = method.instructions.iterator + while (it.hasNext) it.next() match { + case vi: VarInsnNode if vi.`var` >= numParams && isLoad(vi) => + val aliases = aliasAnalysis.frameAt(vi).asInstanceOf[AliasingFrame[_]].aliasesOf(vi.`var`) + if (aliases.size > 1) { + val alias = usedOrMinAlias(aliases.iterator, vi.`var`) + if (alias != -1) { + changed = true + vi.`var` = alias + } + } + knownUsed(vi.`var`) = true + + case _ => + } + + changed + } + } + + /** + * Eliminate `xSTORE` instructions that have no consumer. If the instruction can be completely + * eliminated, it is replaced by a POP. The [[eliminatePushPop]] cleans up unnecessary POPs. + * + * Note that an `ASOTRE` can not always be eliminated: it removes a reference to the object that + * is currently stored in that local, which potentially frees it for GC (SI-5313). Therefore + * we replace such stores by `POP; ACONST_NULL; ASTORE x`. + */ + def eliminateStaleStores(method: MethodNode, owner: InternalName): Boolean = { + AsmAnalyzer.sizeOKForSourceValue(method) && { + lazy val prodCons = new ProdConsAnalyzer(method, owner) + def hasNoCons(varIns: AbstractInsnNode, slot: Int) = prodCons.consumersOfValueAt(varIns.getNext, slot).isEmpty + + // insns to delete: IINC that have no consumer + val toDelete = mutable.ArrayBuffer.empty[IincInsnNode] + + // xSTORE insns to be replaced by POP or POP2 + val storesToDrop = mutable.ArrayBuffer.empty[VarInsnNode] + + // ASTORE insn that have no consumer. + // - if the local is not live, the store is replaced by POP + // - otherwise, pop the argument value and store NULL instead. Unless the boolean field is + // `true`: then the store argument is already known to be ACONST_NULL. + val toNullOut = mutable.ArrayBuffer.empty[(VarInsnNode, Boolean)] + + // `true` for variables that are known to be live + val liveVars = new Array[Boolean](method.maxLocals) + + val it = method.instructions.iterator + while (it.hasNext) it.next() match { + case vi: VarInsnNode if isStore(vi) && hasNoCons(vi, vi.`var`) => + val canElim = vi.getOpcode != ASTORE || { + val currentFieldValueProds = prodCons.initialProducersForValueAt(vi, vi.`var`) + currentFieldValueProds.size == 1 && (currentFieldValueProds.head match { + case ParameterProducer(0) => !isStaticMethod(method) // current field value is `this`, which won't be gc'd anyway + case _: UninitializedLocalProducer => true // field is not yet initialized, so current value cannot leak + case _ => false + }) + } + if (canElim) storesToDrop += vi + else { + val prods = prodCons.producersForValueAt(vi, prodCons.frameAt(vi).stackTop) + val isStoreNull = prods.size == 1 && prods.head.getOpcode == ACONST_NULL + toNullOut += ((vi, isStoreNull)) + } + + case ii: IincInsnNode if hasNoCons(ii, ii.`var`) => + toDelete += ii + + case vi: VarInsnNode => + liveVars(vi.`var`) = true + + case ii: IincInsnNode => + liveVars(ii.`var`) = true + + case _ => + } + + def replaceByPop(vi: VarInsnNode): Unit = { + val size = if (isSize2LoadOrStore(vi.getOpcode)) 2 else 1 + method.instructions.set(vi, getPop(size)) + } + + toDelete foreach method.instructions.remove + + storesToDrop foreach replaceByPop + + for ((vi, isStoreNull) <- toNullOut) { + if (!liveVars(vi.`var`)) replaceByPop(vi) // can drop `ASTORE x` where x has only dead stores + else { + if (!isStoreNull) { + val prev = vi.getPrevious + method.instructions.insert(prev, new InsnNode(ACONST_NULL)) + method.instructions.insert(prev, getPop(1)) + } + } + } + + toDelete.nonEmpty || storesToDrop.nonEmpty || toNullOut.nonEmpty + } + } + + /** + * When a POP instruction has a single producer, remove the POP and eliminate the producer by + * bubbling up the POPs. For example, given + * ILOAD 1; ILOAD 2; IADD; POP + * we first eliminate the POP, then the IADD, then its inputs, so the entire sequence goes away. + * If a producer cannot be eliminated (need to keep side-effects), a POP is inserted. + * + * A special case eliminates the creation of unused objects with side-effect-free constructors: + * NEW scala/Tuple1; DUP; ALOAD 0; INVOKESPECIAL scala/Tuple1.<init>; POP + * The POP has a single producer (the DUP), it's easy to eliminate these two. A special case + * is needed to eliminate the INVOKESPECIAL and NEW. + */ + def eliminatePushPop(method: MethodNode, owner: InternalName): Boolean = { + AsmAnalyzer.sizeOKForSourceValue(method) && { + // A queue of instructions producing a value that has to be eliminated. If possible, the + // instruction (and its inputs) will be removed, otherwise a POP is inserted after + val queue = mutable.Queue.empty[ProducedValue] + // Contains constructor invocations for values that can be eliminated if unused. + val sideEffectFreeConstructorCalls = mutable.ArrayBuffer.empty[MethodInsnNode] + + // instructions to remove (we don't change the bytecode while analyzing it. this allows + // running the ProdConsAnalyzer only once.) + val toRemove = mutable.Set.empty[AbstractInsnNode] + // instructions to insert before some instruction + val toInsertBefore = mutable.Map.empty[AbstractInsnNode, List[InsnNode]] + // an instruction to insert after some instruction + val toInsertAfter = mutable.Map.empty[AbstractInsnNode, AbstractInsnNode] + + lazy val prodCons = new ProdConsAnalyzer(method, owner) + + /** + * Returns the producers for the stack value `inputSlot` consumed by `cons`, if the consumer + * instruction is the only consumer for all of these producers. + * + * If a producer has multiple consumers, or the value is the caught exception in a catch + * block, this method returns Set.empty. + */ + def producersIfSingleConsumer(cons: AbstractInsnNode, inputSlot: Int): Set[AbstractInsnNode] = { + /** + * True if the values produced by `prod` are all the same. Most instructions produce a single + * value. DUP and DUP2 (with a size-2 input) produce two equivalent values. However, there + * are some exotic instructions that produce multiple non-equal values (DUP_X1, SWAP, ...). + * + * Assume we have `DUP_X2; POP`. In order to remove the `POP` we need to change the DUP_X2 + * into something else, which is not straightforward. + * + * Since scalac never emits any of those exotic bytecodes, we don't optimize them. + */ + def producerHasSingleOutput(prod: AbstractInsnNode): Boolean = prod match { + case _: ExceptionProducer[_] | _: UninitializedLocalProducer => + // POP of an exception in a catch block cannot be removed. For an uninitialized local, + // there should not be a consumer. We are conservative and include it here, so the + // producer would not be removed. + false + + case _: ParameterProducer => + true + + case _ => (prod.getOpcode: @switch) match { + case DUP => true + case DUP2 => prodCons.frameAt(prod).peekStack(0).getSize == 2 + case _ => InstructionStackEffect.prod(InstructionStackEffect.forAsmAnalysis(prod, prodCons.frameAt(prod))) == 1 + } + } + + val prods = prodCons.producersForValueAt(cons, inputSlot) + val singleConsumer = prods forall { prod => + producerHasSingleOutput(prod) && { + // for DUP / DUP2, we only consider the value that is actually consumed by cons + val conss = prodCons.consumersOfValueAt(prod.getNext, inputSlot) + conss.size == 1 && conss.head == cons + } + } + if (singleConsumer) prods else Set.empty + } + + /** + * For a POP instruction that is the single consumer of its producers, remove the POP and + * enqueue the producers. + */ + def handleInitialPop(pop: AbstractInsnNode): Unit = { + val prods = producersIfSingleConsumer(pop, prodCons.frameAt(pop).stackTop) + if (prods.nonEmpty) { + toRemove += pop + val size = if (pop.getOpcode == POP2) 2 else 1 + queue ++= prods.map(ProducedValue(_, size)) + } + } + + /** + * Traverse the method in its initial state and collect all POP instructions and side-effect + * free constructor invocations that can be eliminated. + */ + def collectInitialPopsAndPureConstrs(): Unit = { + val it = method.instructions.iterator + while (it.hasNext) { + val insn = it.next() + (insn.getOpcode: @switch) match { + case POP | POP2 => + handleInitialPop(insn) + + case INVOKESPECIAL => + val mi = insn.asInstanceOf[MethodInsnNode] + if (isSideEffectFreeConstructorCall(mi)) sideEffectFreeConstructorCalls += mi + + case _ => + } + } + } + + /** + * Eliminate the `numArgs` inputs of the instruction `prod` (which was eliminated). For + * each input value + * - if the `prod` instruction is the single consumer, enqueue the producers of the input + * - otherwise, insert a POP instruction to POP the input value + */ + def handleInputs(prod: AbstractInsnNode, numArgs: Int): Unit = { + val frame = prodCons.frameAt(prod) + val pops = mutable.ListBuffer.empty[InsnNode] + @tailrec def handle(stackOffset: Int): Unit = { + if (stackOffset >= 0) { + val prods = producersIfSingleConsumer(prod, frame.stackTop - stackOffset) + val nSize = frame.peekStack(stackOffset).getSize + if (prods.isEmpty) pops append getPop(nSize) + else queue ++= prods.map(ProducedValue(_, nSize)) + handle(stackOffset - 1) + } + } + handle(numArgs - 1) // handle stack offsets (numArgs - 1) to 0 + if (pops.nonEmpty) toInsertBefore(prod) = pops.toList + } + + /** + * Eliminate LMF `indy` and its inputs. + */ + def handleClosureInst(indy: InvokeDynamicInsnNode): Unit = { + toRemove += indy + callGraph.removeClosureInstantiation(indy, method) + handleInputs(indy, Type.getArgumentTypes(indy.desc).length) + } + + def runQueue(): Unit = while (queue.nonEmpty) { + val ProducedValue(prod, size) = queue.dequeue() + + def prodString = s"Producer ${AsmUtils textify prod}@${method.instructions.indexOf(prod)}\n${AsmUtils textify method}" + def popAfterProd(): Unit = toInsertAfter(prod) = getPop(size) + + (prod.getOpcode: @switch) match { + case ACONST_NULL | ICONST_M1 | ICONST_0 | ICONST_1 | ICONST_2 | ICONST_3 | ICONST_4 | ICONST_5 | LCONST_0 | LCONST_1 | FCONST_0 | FCONST_1 | FCONST_2 | DCONST_0 | DCONST_1 | + BIPUSH | SIPUSH | ILOAD | LLOAD | FLOAD | DLOAD | ALOAD=> + toRemove += prod + + case opc @ (DUP | DUP2) => + assert(opc != 2 || size == 2, s"DUP2 for two size-1 values; $prodString") // ensured in method `producerHasSingleOutput` + if (toRemove(prod)) + // the DUP is already scheduled for removal because one of its consumers is a POP. + // now the second consumer is also a POP, so we need to eliminate the DUP's input. + handleInputs(prod, 1) + else + toRemove += prod + + case DUP_X1 | DUP_X2 | DUP2_X1 | DUP2_X2 | SWAP => + // these are excluded in method `producerHasSingleOutput` + assert(false, s"Cannot eliminate value pushed by an instruction with multiple output values; $prodString") + + case IDIV | LDIV | IREM | LREM => + popAfterProd() // keep potential division by zero + + case IADD | LADD | FADD | DADD | ISUB | LSUB | FSUB | DSUB | IMUL | LMUL | FMUL | DMUL | FDIV | DDIV | FREM | DREM | + LSHL | LSHR | LUSHR | + IAND | IOR | IXOR | LAND | LOR | LXOR | + LCMP | FCMPL | FCMPG | DCMPL | DCMPG => + toRemove += prod + handleInputs(prod, 2) + + case INEG | LNEG | FNEG | DNEG | + I2L | I2F | I2D | L2I | L2F | L2D | F2I | F2L | F2D | D2I | D2L | D2F | I2B | I2C | I2S => + toRemove += prod + handleInputs(prod, 1) + + case GETFIELD | GETSTATIC => + // TODO eliminate side-effect free module loads (https://github.com/scala/scala-dev/issues/16) + if (isBoxedUnit(prod)) toRemove += prod + else popAfterProd() // keep potential class initialization (static field) or NPE (instance field) + + case INVOKEVIRTUAL | INVOKESPECIAL | INVOKESTATIC | INVOKEINTERFACE => + val methodInsn = prod.asInstanceOf[MethodInsnNode] + if (isSideEffectFreeCall(methodInsn)) { + toRemove += prod + callGraph.removeCallsite(methodInsn, method) + val receiver = if (methodInsn.getOpcode == INVOKESTATIC) 0 else 1 + handleInputs(prod, Type.getArgumentTypes(methodInsn.desc).length + receiver) + } else + popAfterProd() + + case INVOKEDYNAMIC => + prod match { + case callGraph.LambdaMetaFactoryCall(indy, _, _, _) => handleClosureInst(indy) + case _ => popAfterProd() + } + + case NEW => + if (isNewForSideEffectFreeConstructor(prod)) toRemove += prod + else popAfterProd() + + case LDC => prod.asInstanceOf[LdcInsnNode].cst match { + case _: java.lang.Integer | _: java.lang.Float | _: java.lang.Long | _: java.lang.Double | _: String => + toRemove += prod + + case _ => + // don't remove class literals, method types, method handles: keep a potential NoClassDefFoundError + popAfterProd() + } + + case MULTIANEWARRAY => + toRemove += prod + handleInputs(prod, prod.asInstanceOf[MultiANewArrayInsnNode].dims) + + case _ => + popAfterProd() + } + } + + // there are two cases when we can eliminate a constructor call: + // - NEW T; INVOKESPECIAL T.<init> -- there's no DUP, the new object is consumed only by the constructor) + // - NEW T; DUP; INVOKESPECIAL T.<init>, where the DUP will be removed + def eliminateUnusedPureConstructorCalls(): Boolean = { + var changed = false + + def removeConstructorCall(mi: MethodInsnNode): Unit = { + toRemove += mi + callGraph.removeCallsite(mi, method) + sideEffectFreeConstructorCalls -= mi + changed = true + } + + for (mi <- sideEffectFreeConstructorCalls.toList) { // toList to allow removing elements while traversing + val frame = prodCons.frameAt(mi) + val stackTop = frame.stackTop + val numArgs = Type.getArgumentTypes(mi.desc).length + val receiverProds = producersIfSingleConsumer(mi, stackTop - numArgs) + if (receiverProds.size == 1) { + val receiverProd = receiverProds.head + if (receiverProd.getOpcode == NEW) { + removeConstructorCall(mi) + handleInputs(mi, numArgs + 1) // removes the producers of args and receiver + } else if (receiverProd.getOpcode == DUP && toRemove.contains(receiverProd)) { + val dupProds = producersIfSingleConsumer(receiverProd, prodCons.frameAt(receiverProd).stackTop) + if (dupProds.size == 1 && dupProds.head.getOpcode == NEW) { + removeConstructorCall(mi) + handleInputs(mi, numArgs) // removes the producers of args. the producer of the receiver is DUP and already in toRemove. + queue += ProducedValue(dupProds.head, 1) // removes the NEW (which is NOT the producer of the receiver!) + } + } + } + } + changed + } + + collectInitialPopsAndPureConstrs() + + // eliminating producers enables eliminating unused constructor calls (when a DUP gets removed). + // vice-versa, eliminating a constructor call adds producers of constructor parameters to the queue. + // so the two run in a loop. + runQueue() + while (eliminateUnusedPureConstructorCalls()) + runQueue() + + var changed = false + toInsertAfter foreach { + case (target, insn) => + nextExecutableInstructionOrLabel(target) match { + // `insn` is of type `InsnNode`, so we only need to check the Opcode when comparing to another instruction + case Some(next) if next.getOpcode == insn.getOpcode && toRemove(next) => + // Inserting and removing a POP at the same place should not enable `changed`. This happens + // when a POP directly follows a producer that cannot be eliminated, e.g. INVOKESTATIC A.m ()I; POP + // The POP is initially added to `toRemove`, and the `INVOKESTATIC` producer is added to the queue. + // Because the producer cannot be elided, a POP is added to `toInsertAfter`. + toRemove -= next + + case _ => + changed = true + method.instructions.insert(target, insn) + } + } + toInsertBefore foreach { + case (target, insns) => + changed = true + insns.foreach(method.instructions.insertBefore(target, _)) + } + toRemove foreach { insn => + changed = true + method.instructions.remove(insn) + } + changed + } + } + + case class ProducedValue(producer: AbstractInsnNode, size: Int) { + override def toString = s"<${AsmUtils textify producer}>" + } + + /** + * Remove `xSTORE n; xLOAD n` pairs if + * - the local variable n is not used anywhere else in the method (1), and + * - there are no executable instructions and no live labels (jump targets) between the two (2) + * + * Note: store-load pairs that cannot be eliminated could be replaced by `DUP; xSTORE n`, but + * that's just cosmetic and doesn't help for anything. + * + * (1) This could be made more precise by running a prodCons analysis and checking that the load + * is the only user of the store. Then we could eliminate the pair even if the variable is live + * (except for ASTORE, SI-5313). Not needing an analyzer is more efficient, and catches most + * cases. + * + * (2) The implementation uses a conservative estimation for liveness (if some instruction uses + * local n, then n is considered live in the entire method). In return, it doesn't need to run an + * Analyzer on the method, making it more efficient. + * + * This method also removes `ACONST_NULL; ASTORE n` if the local n is not live. This pattern is + * introduced by [[eliminateStaleStores]]. + * + * The implementation is a little tricky to support the following case: + * ISTORE 1; ISTORE 2; ILOAD 2; ACONST_NULL; ASTORE 3; ILOAD 1 + * The outer store-load pair can be removed if two the inner pairs can be. + */ + def eliminateStoreLoad(method: MethodNode): Boolean = { + val removePairs = mutable.Set.empty[RemovePair] + val liveVars = new Array[Boolean](method.maxLocals) + val liveLabels = mutable.Set.empty[LabelNode] + + def mkRemovePair(store: VarInsnNode, other: AbstractInsnNode, depends: List[RemovePairDependency]): RemovePair = { + val r = RemovePair(store, other, depends) + removePairs += r + r + } + + def registerLiveVarsLabels(insn: AbstractInsnNode): Unit = insn match { + case vi: VarInsnNode => liveVars(vi.`var`) = true + case ii: IincInsnNode => liveVars(ii.`var`) = true + case j: JumpInsnNode => liveLabels += j.label + case s: TableSwitchInsnNode => liveLabels += s.dflt; liveLabels ++= s.labels.asScala + case s: LookupSwitchInsnNode => liveLabels += s.dflt; liveLabels ++= s.labels.asScala + case _ => + } + + val pairStartStack = new mutable.Stack[(AbstractInsnNode, mutable.ListBuffer[RemovePairDependency])] + + def push(insn: AbstractInsnNode) = { + pairStartStack push ((insn, mutable.ListBuffer.empty)) + } + + def addDepends(dependency: RemovePairDependency) = if (pairStartStack.nonEmpty) { + val (_, depends) = pairStartStack.top + depends += dependency + } + + def completesStackTop(load: AbstractInsnNode) = isLoad(load) && pairStartStack.nonEmpty && { + pairStartStack.top match { + case (store: VarInsnNode, _) => store.`var` == load.asInstanceOf[VarInsnNode].`var` + case _ => false + } + } + + /** + * Try to pair `insn` with its correspondent on the stack + * - if the stack top is a store and `insn` is a corresponding load, create a pair + * - otherwise, check the two top stack values for `null; store`. if it matches, create + * a pair and continue pairing `insn` on the remaining stack + * - otherwise, empty the stack and mark the local variables in it live + */ + def tryToPairInstruction(insn: AbstractInsnNode): Unit = { + @tailrec def emptyStack(): Unit = if (pairStartStack.nonEmpty) { + registerLiveVarsLabels(pairStartStack.pop()._1) + emptyStack() + } + + @tailrec def tryPairing(): Unit = { + if (completesStackTop(insn)) { + val (store: VarInsnNode, depends) = pairStartStack.pop() + addDepends(mkRemovePair(store, insn, depends.toList)) + } else if (pairStartStack.nonEmpty) { + val (top, topDepends) = pairStartStack.pop() + if (pairStartStack.nonEmpty) { + (pairStartStack.top, top) match { + case ((ldNull: InsnNode, depends), store: VarInsnNode) if ldNull.getOpcode == ACONST_NULL && store.getOpcode == ASTORE => + pairStartStack.pop() + addDepends(mkRemovePair(store, ldNull, depends.toList)) + // example: store; (null; store;) (store; load;) load + // s1^ ^^^^^p1^^^^^ // p1 is added to s1's depends + // then: store; (null; store;) load + // s2^ ^^^^p2^^^^^ // p1 and p2 are added to s2's depends + topDepends foreach addDepends + tryPairing() + + case _ => + // empty the stack - a non-matching insn was found, cannot create any pairs to remove + registerLiveVarsLabels(insn) + registerLiveVarsLabels(top) + emptyStack() + } + } else { + // stack only has one element + registerLiveVarsLabels(insn) + registerLiveVarsLabels(top) + } + } else { + // stack is empty already + registerLiveVarsLabels(insn) + } + } + + tryPairing() + } + + + var insn = method.instructions.getFirst + + @tailrec def advanceToNextExecutableOrLabel(): Unit = { + insn = insn.getNext + if (insn != null && !isExecutable(insn) && !insn.isInstanceOf[LabelNode]) advanceToNextExecutableOrLabel() + } + + while (insn != null) { + insn match { + case _ if insn.getOpcode == ACONST_NULL => push(insn) + case vi: VarInsnNode if isStore(vi) => push(insn) + case label: LabelNode if pairStartStack.nonEmpty => addDepends(LabelNotLive(label)) + case _ => tryToPairInstruction(insn) + } + advanceToNextExecutableOrLabel() + } + + // elide RemovePairs that depend on live labels or other RemovePair that have to be elided. + // example: store 1; store 2; label x; load 2; load 1 + // if x is live, the inner pair has to be elided, causing the outer pair to be elided too. + + var doneEliding = false + + def elide(removePair: RemovePair) = { + doneEliding = false + liveVars(removePair.store.`var`) = true + removePairs -= removePair + } + + while (!doneEliding) { + doneEliding = true + for (removePair <- removePairs.toList) { + val slot = removePair.store.`var` + if (liveVars(slot)) elide(removePair) + else removePair.depends foreach { + case LabelNotLive(label) => if (liveLabels(label)) elide(removePair) + case other: RemovePair => if (!removePairs(other)) elide(removePair) + } + } + } + + for (removePair <- removePairs) { + method.instructions.remove(removePair.store) + method.instructions.remove(removePair.other) + } + + removePairs.nonEmpty + } +} + +trait RemovePairDependency +case class RemovePair(store: VarInsnNode, other: AbstractInsnNode, depends: List[RemovePairDependency]) extends RemovePairDependency { + override def toString = s"<${AsmUtils textify store},${AsmUtils textify other}> [$depends]" +} +case class LabelNotLive(label: LabelNode) extends RemovePairDependency diff --git a/src/compiler/scala/tools/nsc/backend/jvm/opt/InlineInfoAttribute.scala b/src/compiler/scala/tools/nsc/backend/jvm/opt/InlineInfoAttribute.scala index e7dd5abc57..7bc4ea2392 100644 --- a/src/compiler/scala/tools/nsc/backend/jvm/opt/InlineInfoAttribute.scala +++ b/src/compiler/scala/tools/nsc/backend/jvm/opt/InlineInfoAttribute.scala @@ -27,7 +27,7 @@ import scala.tools.nsc.backend.jvm.BackendReporting.UnknownScalaInlineInfoVersio * In principle we could encode the InlineInfo into a Java annotation (instead of a classfile attribute). * However, an attribute allows us to save many bits. In particular, note that the strings in an * InlineInfo are serialized as references to constants in the constant pool, and those strings - * (traitImplClassSelfType, method names, method signatures) would exist in there anyway. So the + * (method names, method signatures) would exist in there anyway. So the * ScalaInlineAttribute remains relatively compact. */ case class InlineInfoAttribute(inlineInfo: InlineInfo) extends Attribute(InlineInfoAttribute.attributeName) { @@ -47,13 +47,16 @@ case class InlineInfoAttribute(inlineInfo: InlineInfo) extends Attribute(InlineI result.putByte(InlineInfoAttribute.VERSION) - var hasSelfIsFinal = 0 - if (inlineInfo.isEffectivelyFinal) hasSelfIsFinal |= 1 - if (inlineInfo.traitImplClassSelfType.isDefined) hasSelfIsFinal |= 2 - result.putByte(hasSelfIsFinal) + var flags = 0 + if (inlineInfo.isEffectivelyFinal) flags |= 1 + // flags |= 2 // no longer written + if (inlineInfo.sam.isDefined) flags |= 4 + result.putByte(flags) - for (selfInternalName <- inlineInfo.traitImplClassSelfType) { - result.putShort(cw.newUTF8(selfInternalName)) + for (samNameDesc <- inlineInfo.sam) { + val (name, desc) = samNameDesc.span(_ != '(') + result.putShort(cw.newUTF8(name)) + result.putShort(cw.newUTF8(desc)) } // The method count fits in a short (the methods_count in a classfile is also a short) @@ -68,10 +71,10 @@ case class InlineInfoAttribute(inlineInfo: InlineInfo) extends Attribute(InlineI result.putShort(cw.newUTF8(desc)) var inlineInfo = 0 - if (info.effectivelyFinal) inlineInfo |= 1 - if (info.traitMethodWithStaticImplementation) inlineInfo |= 2 - if (info.annotatedInline) inlineInfo |= 4 - if (info.annotatedNoInline) inlineInfo |= 8 + if (info.effectivelyFinal) inlineInfo |= 1 + // inlineInfo |= 2 // no longer written + if (info.annotatedInline) inlineInfo |= 4 + if (info.annotatedNoInline) inlineInfo |= 8 result.putByte(inlineInfo) } @@ -79,7 +82,7 @@ case class InlineInfoAttribute(inlineInfo: InlineInfo) extends Attribute(InlineI } /** - * De-serialize the attribute into an InlineInfo. The attribute starts at cr.b(off), but we don't + * Deserialize the attribute into an InlineInfo. The attribute starts at cr.b(off), but we don't * need to access that array directly, we can use the `read` methods provided by the ClassReader. * * `buf` is a pre-allocated character array that is guaranteed to be long enough to hold any @@ -94,15 +97,17 @@ case class InlineInfoAttribute(inlineInfo: InlineInfo) extends Attribute(InlineI val version = nextByte() if (version == 1) { - val hasSelfIsFinal = nextByte() - val isFinal = (hasSelfIsFinal & 1) != 0 - val hasSelf = (hasSelfIsFinal & 2) != 0 - - val self = if (hasSelf) { - val selfName = nextUTF8() - Some(selfName) - } else { - None + val flags = nextByte() + val isFinal = (flags & 1) != 0 + val hasSelf = (flags & 2) != 0 + val hasSam = (flags & 4) != 0 + + if (hasSelf) nextUTF8() // no longer used + + val sam = if (!hasSam) None else { + val name = nextUTF8() + val desc = nextUTF8() + Some(name + desc) } val numEntries = nextShort() @@ -111,14 +116,15 @@ case class InlineInfoAttribute(inlineInfo: InlineInfo) extends Attribute(InlineI val desc = nextUTF8() val inlineInfo = nextByte() - val isFinal = (inlineInfo & 1) != 0 - val traitMethodWithStaticImplementation = (inlineInfo & 2) != 0 - val isInline = (inlineInfo & 4) != 0 - val isNoInline = (inlineInfo & 8) != 0 - (name + desc, MethodInlineInfo(isFinal, traitMethodWithStaticImplementation, isInline, isNoInline)) + val isFinal = (inlineInfo & 1) != 0 + // = (inlineInfo & 2) != 0 // no longer used + val isInline = (inlineInfo & 4) != 0 + val isNoInline = (inlineInfo & 8) != 0 + (name + desc, MethodInlineInfo(isFinal, isInline, isNoInline)) }).toMap - InlineInfoAttribute(InlineInfo(self, isFinal, infos, None)) + val info = InlineInfo(isFinal, sam, infos, None) + InlineInfoAttribute(info) } else { val msg = UnknownScalaInlineInfoVersion(cr.getClassName, version) InlineInfoAttribute(BTypes.EmptyInlineInfo.copy(warning = Some(msg))) @@ -128,9 +134,18 @@ case class InlineInfoAttribute(inlineInfo: InlineInfo) extends Attribute(InlineI object InlineInfoAttribute { /** + * Notes: + * - `traitImplClassSelfType` is no longer emitted, `hasTraitImplClassSelfType` is always emitted + * as 0. Similarly, `traitMethodWithStaticImplementation` is always emitted 0. + * - When reading an existing attribute where `hasTraitImplClassSelfType` is 1, the + * `traitImplClassSelfType` is ignored. Also the value of `traitMethodWithStaticImplementation` + * is ignored. + * * [u1] version - * [u1] isEffectivelyFinal (<< 0), hasTraitImplClassSelfType (<< 1) + * [u1] isEffectivelyFinal (<< 0), hasTraitImplClassSelfType (<< 1), hasSam (<< 2), hasLateInterfaces (<< 3) * [u2]? traitImplClassSelfType (reference) + * [u2]? samName (reference) + * [u2]? samDescriptor (reference) * [u2] numMethodEntries * [u2] name (reference) * [u2] descriptor (reference) @@ -142,7 +157,7 @@ object InlineInfoAttribute { } /** - * In order to instruct the ASM framework to de-serialize the ScalaInlineInfo attribute, we need + * In order to instruct the ASM framework to deserialize the ScalaInlineInfo attribute, we need * to pass a prototype instance when running the class reader. */ -object InlineInfoAttributePrototype extends InlineInfoAttribute(InlineInfo(null, false, null, null)) +object InlineInfoAttributePrototype extends InlineInfoAttribute(InlineInfo(false, null, null, null)) diff --git a/src/compiler/scala/tools/nsc/backend/jvm/opt/Inliner.scala b/src/compiler/scala/tools/nsc/backend/jvm/opt/Inliner.scala index 6b2786c1a3..1c29859f46 100644 --- a/src/compiler/scala/tools/nsc/backend/jvm/opt/Inliner.scala +++ b/src/compiler/scala/tools/nsc/backend/jvm/opt/Inliner.scala @@ -9,59 +9,125 @@ package opt import scala.annotation.tailrec import scala.tools.asm -import asm.Handle import asm.Opcodes._ import asm.tree._ -import scala.collection.convert.decorateAsScala._ -import scala.collection.convert.decorateAsJava._ +import scala.collection.JavaConverters._ import AsmUtils._ import BytecodeUtils._ import collection.mutable -import scala.tools.asm.tree.analysis.SourceInterpreter import BackendReporting._ import scala.tools.nsc.backend.jvm.BTypes.InternalName class Inliner[BT <: BTypes](val btypes: BT) { import btypes._ import callGraph._ + import inlinerHeuristics._ + import backendUtils._ - def eliminateUnreachableCodeAndUpdateCallGraph(methodNode: MethodNode, definingClass: InternalName): Unit = { - localOpt.minimalRemoveUnreachableCode(methodNode, definingClass) foreach { - case invocation: MethodInsnNode => callGraph.callsites.remove(invocation) - case indy: InvokeDynamicInsnNode => callGraph.closureInstantiations.remove(indy) - case _ => + sealed trait InlineLog { + def request: InlineRequest + } + final case class InlineLogSuccess(request: InlineRequest, sizeBefore: Int, sizeInlined: Int) extends InlineLog { + var downstreamLog: mutable.Buffer[InlineLog] = mutable.ListBuffer.empty + } + final case class InlineLogFail(request: InlineRequest, warning: CannotInlineWarning) extends InlineLog + final case class InlineLogRollback(request: InlineRequest, warnings: List[CannotInlineWarning]) extends InlineLog + + object InlineLog { + private def shouldLog(request: InlineRequest): Boolean = { + def logEnabled = compilerSettings.YoptLogInline.isSetByUser + def matchesName = { + val prefix = compilerSettings.YoptLogInline.value match { + case "_" => "" + case p => p + } + val name: String = request.callsite.callsiteClass.internalName + "." + request.callsite.callsiteMethod.name + name startsWith prefix + } + logEnabled && (upstream != null || (isTopLevel && matchesName)) + } + + // indexed by callsite method + private val logs = mutable.Map.empty[MethodNode, mutable.LinkedHashSet[InlineLog]] + + private var upstream: InlineLogSuccess = _ + private var isTopLevel = true + + def withInlineLogging[T](request: InlineRequest)(inlineRequest: => Unit)(inlinePost: => T): T = { + def doInlinePost(): T = { + val savedIsTopLevel = isTopLevel + isTopLevel = false + try inlinePost + finally isTopLevel = savedIsTopLevel + } + if (shouldLog(request)) { + val sizeBefore = request.callsite.callsiteMethod.instructions.size + inlineRequest + val log = InlineLogSuccess(request, sizeBefore, request.callsite.callee.get.callee.instructions.size) + apply(log) + + val savedUpstream = upstream + upstream = log + try doInlinePost() + finally upstream = savedUpstream + } else { + inlineRequest + doInlinePost() + } + } + + def apply(log: => InlineLog): Unit = if (shouldLog(log.request)) { + if (upstream != null) upstream.downstreamLog += log + else { + val methodLogs = logs.getOrElseUpdate(log.request.callsite.callsiteMethod, mutable.LinkedHashSet.empty) + methodLogs += log + } + } + + def entryString(log: InlineLog, indent: Int = 0): String = { + val callee = log.request.callsite.callee.get + val calleeString = callee.calleeDeclarationClass.internalName + "." + callee.callee.name + val indentString = " " * indent + log match { + case s @ InlineLogSuccess(_, sizeBefore, sizeInlined) => + val self = s"${indentString}inlined $calleeString. Before: $sizeBefore ins, inlined: $sizeInlined ins." + if (s.downstreamLog.isEmpty) self + else s.downstreamLog.iterator.map(entryString(_, indent + 2)).mkString(self + "\n", "\n", "") + + case InlineLogFail(_, w) => + s"${indentString}failed $calleeString. ${w.toString.replace('\n', ' ')}" + + case InlineLogRollback(_, _) => + s"${indentString}rolling back, nested inline failed." + } + } + + def print(): Unit = if (compilerSettings.YoptLogInline.isSetByUser) { + val byClassAndMethod: List[(InternalName, mutable.Map[MethodNode, mutable.LinkedHashSet[InlineLog]])] = { + logs. + groupBy(_._2.head.request.callsite.callsiteClass.internalName). + toList.sortBy(_._1) + } + for { + (c, methodLogs) <- byClassAndMethod + (m, mLogs) <- methodLogs.toList.sortBy(_._1.name) + mLog <- mLogs // insertion order + } { + println(s"Inline into $c.${m.name}: ${entryString(mLog)}") + } } } def runInliner(): Unit = { - rewriteFinalTraitMethodInvocations() - for (request <- collectAndOrderInlineRequests) { - val Right(callee) = request.callee // collectAndOrderInlineRequests returns callsites with a known callee - - // Inlining a method can create unreachable code. Example: - // def f = throw e - // def g = f; println() // println is unreachable after inlining f - // If we have an inline request for a call to g, and f has been already inlined into g, we - // need to run DCE before inlining g. - eliminateUnreachableCodeAndUpdateCallGraph(callee.callee, callee.calleeDeclarationClass.internalName) - - // DCE above removes unreachable callsites from the call graph. If the inlining request denotes - // such an eliminated callsite, do nothing. - if (callGraph.callsites contains request.callsiteInstruction) { - val r = inline(request.callsiteInstruction, request.callsiteStackHeight, request.callsiteMethod, request.callsiteClass, - callee.callee, callee.calleeDeclarationClass, - request.receiverKnownNotNull, keepLineNumbers = false) - - for (warning <- r) { - if ((callee.annotatedInline && btypes.compilerSettings.YoptWarningEmitAtInlineFailed) || warning.emitWarning(compilerSettings)) { - val annotWarn = if (callee.annotatedInline) " is annotated @inline but" else "" - val msg = s"${BackendReporting.methodSignature(callee.calleeDeclarationClass.internalName, callee.callee)}$annotWarn could not be inlined:\n$warning" - backendReporting.inlinerWarning(request.callsitePosition, msg) - } - } + val Right(callee) = request.callsite.callee // collectAndOrderInlineRequests returns callsites with a known callee + val warnings = inline(request) + for (warning <- warnings) { + if (warning.emitWarning(compilerSettings)) + backendReporting.inlinerWarning(request.callsite.callsitePosition, warning.toString) } } + InlineLog.print() } /** @@ -69,165 +135,21 @@ class Inliner[BT <: BTypes](val btypes: BT) { * - Always remove the same request when breaking inlining cycles * - Perform inlinings in a consistent order */ - object callsiteOrdering extends Ordering[Callsite] { - override def compare(x: Callsite, y: Callsite): Int = { - val cls = x.callsiteClass.internalName compareTo y.callsiteClass.internalName + object callsiteOrdering extends Ordering[InlineRequest] { + override def compare(x: InlineRequest, y: InlineRequest): Int = { + val xCs = x.callsite + val yCs = y.callsite + val cls = xCs.callsiteClass.internalName compareTo yCs.callsiteClass.internalName if (cls != 0) return cls - val name = x.callsiteMethod.name compareTo y.callsiteMethod.name + val name = xCs.callsiteMethod.name compareTo yCs.callsiteMethod.name if (name != 0) return name - val desc = x.callsiteMethod.desc compareTo y.callsiteMethod.desc + val desc = xCs.callsiteMethod.desc compareTo yCs.callsiteMethod.desc if (desc != 0) return desc def pos(c: Callsite) = c.callsiteMethod.instructions.indexOf(c.callsiteInstruction) - pos(x) - pos(y) - } - } - - /** - * Select callsites from the call graph that should be inlined. The resulting list of inlining - * requests is allowed to have cycles, and the callsites can appear in any order. - */ - def selectCallsitesForInlining: List[Callsite] = { - callsites.valuesIterator.filter({ - case callsite @ Callsite(_, _, _, Right(Callee(callee, calleeDeclClass, safeToInline, _, annotatedInline, _, warning)), _, _, _, pos) => - val res = doInlineCallsite(callsite) - - if (!res) { - if (annotatedInline && btypes.compilerSettings.YoptWarningEmitAtInlineFailed) { - // if the callsite is annotated @inline, we report an inline warning even if the underlying - // reason is, for example, mixed compilation (which has a separate -Yopt-warning flag). - def initMsg = s"${BackendReporting.methodSignature(calleeDeclClass.internalName, callee)} is annotated @inline but cannot be inlined" - def warnMsg = warning.map(" Possible reason:\n" + _).getOrElse("") - if (doRewriteTraitCallsite(callsite)) - backendReporting.inlinerWarning(pos, s"$initMsg: the trait method call could not be rewritten to the static implementation method." + warnMsg) - else if (!safeToInline) - backendReporting.inlinerWarning(pos, s"$initMsg: the method is not final and may be overridden." + warnMsg) - else - backendReporting.inlinerWarning(pos, s"$initMsg." + warnMsg) - } else if (warning.isDefined && warning.get.emitWarning(compilerSettings)) { - // when annotatedInline is false, and there is some warning, the callsite metadata is possibly incomplete. - backendReporting.inlinerWarning(pos, s"there was a problem determining if method ${callee.name} can be inlined: \n"+ warning.get) - } - } - - res - - case Callsite(ins, _, _, Left(warning), _, _, _, pos) => - if (warning.emitWarning(compilerSettings)) - backendReporting.inlinerWarning(pos, s"failed to determine if ${ins.name} should be inlined:\n$warning") - false - }).toList - } - - /** - * The current inlining heuristics are simple: inline calls to methods annotated @inline. - */ - def doInlineCallsite(callsite: Callsite): Boolean = callsite match { - case Callsite(_, _, _, Right(Callee(callee, calleeDeclClass, safeToInline, _, annotatedInline, _, warning)), _, _, _, pos) => - if (compilerSettings.YoptInlineHeuristics.value == "everything") safeToInline - else annotatedInline && safeToInline - - case _ => false - } - - def rewriteFinalTraitMethodInvocations(): Unit = { - // Rewriting final trait method callsites to the implementation class enables inlining. - // We cannot just iterate over the values of the `callsites` map because the rewrite changes the - // map. Therefore we first copy the values to a list. - callsites.values.toList.foreach(rewriteFinalTraitMethodInvocation) - } - - /** - * True for statically resolved trait callsites that should be rewritten to the static implementation method. - */ - def doRewriteTraitCallsite(callsite: Callsite) = callsite.callee match { - case Right(Callee(callee, calleeDeclarationClass, safeToInline, true, annotatedInline, annotatedNoInline, infoWarning)) => true - case _ => false - } - - /** - * Rewrite the INVOKEINTERFACE callsite of a final trait method invocation to INVOKESTATIC of the - * corresponding method in the implementation class. This enables inlining final trait methods. - * - * In a final trait method callsite, the callee is safeToInline and the callee method is abstract - * (the receiver type is the interface, so the method is abstract). - */ - def rewriteFinalTraitMethodInvocation(callsite: Callsite): Unit = { - if (doRewriteTraitCallsite(callsite)) { - val Right(Callee(callee, calleeDeclarationClass, _, _, annotatedInline, annotatedNoInline, infoWarning)) = callsite.callee - - val traitMethodArgumentTypes = asm.Type.getArgumentTypes(callee.desc) - - val implClassInternalName = calleeDeclarationClass.internalName + "$class" - - val selfParamTypeV: Either[OptimizerWarning, ClassBType] = calleeDeclarationClass.info.map(_.inlineInfo.traitImplClassSelfType match { - case Some(internalName) => classBTypeFromParsedClassfile(internalName) - case None => calleeDeclarationClass - }) - - def implClassMethodV(implMethodDescriptor: String): Either[OptimizerWarning, MethodNode] = { - byteCodeRepository.methodNode(implClassInternalName, callee.name, implMethodDescriptor).map(_._1) - } - - // The rewrite reading the implementation class and the implementation method from the bytecode - // repository. If either of the two fails, the rewrite is not performed. - val res = for { - selfParamType <- selfParamTypeV - implMethodDescriptor = asm.Type.getMethodDescriptor(asm.Type.getReturnType(callee.desc), selfParamType.toASMType +: traitMethodArgumentTypes: _*) - implClassMethod <- implClassMethodV(implMethodDescriptor) - implClassBType = classBTypeFromParsedClassfile(implClassInternalName) - selfTypeOk <- calleeDeclarationClass.isSubtypeOf(selfParamType) - } yield { - - // The self parameter type may be incompatible with the trait type. - // trait T { self: S => def foo = 1 } - // The $self parameter type of T$class.foo is S, which may be unrelated to T. If we re-write - // a call to T.foo to T$class.foo, we need to cast the receiver to S, otherwise we get a - // VerifyError. We run a `SourceInterpreter` to find all producer instructions of the - // receiver value and add a cast to the self type after each. - if (!selfTypeOk) { - // there's no need to run eliminateUnreachableCode here. building the call graph does that - // already, no code can become unreachable in the meantime. - val analyzer = new AsmAnalyzer(callsite.callsiteMethod, callsite.callsiteClass.internalName, new SourceInterpreter) - val receiverValue = analyzer.frameAt(callsite.callsiteInstruction).peekStack(traitMethodArgumentTypes.length) - for (i <- receiverValue.insns.asScala) { - val cast = new TypeInsnNode(CHECKCAST, selfParamType.internalName) - callsite.callsiteMethod.instructions.insert(i, cast) - } - } - - val newCallsiteInstruction = new MethodInsnNode(INVOKESTATIC, implClassInternalName, callee.name, implMethodDescriptor, false) - callsite.callsiteMethod.instructions.insert(callsite.callsiteInstruction, newCallsiteInstruction) - callsite.callsiteMethod.instructions.remove(callsite.callsiteInstruction) - - callGraph.callsites.remove(callsite.callsiteInstruction) - val staticCallsite = Callsite( - callsiteInstruction = newCallsiteInstruction, - callsiteMethod = callsite.callsiteMethod, - callsiteClass = callsite.callsiteClass, - callee = Right(Callee( - callee = implClassMethod, - calleeDeclarationClass = implClassBType, - safeToInline = true, - safeToRewrite = false, - annotatedInline = annotatedInline, - annotatedNoInline = annotatedNoInline, - calleeInfoWarning = infoWarning)), - argInfos = Nil, - callsiteStackHeight = callsite.callsiteStackHeight, - receiverKnownNotNull = callsite.receiverKnownNotNull, - callsitePosition = callsite.callsitePosition - ) - callGraph.callsites(newCallsiteInstruction) = staticCallsite - } - - for (warning <- res.left) { - val Right(callee) = callsite.callee - val newCallee = callee.copy(calleeInfoWarning = Some(RewriteTraitCallToStaticImplMethodFailed(calleeDeclarationClass.internalName, callee.callee.name, callee.callee.desc, warning))) - callGraph.callsites(callsite.callsiteInstruction) = callsite.copy(callee = Right(newCallee)) - } + pos(xCs) - pos(yCs) } } @@ -238,15 +160,13 @@ class Inliner[BT <: BTypes](val btypes: BT) { * The resulting list is sorted such that the leaves of the inline request graph are on the left. * Once these leaves are inlined, the successive elements will be leaves, etc. */ - private def collectAndOrderInlineRequests: List[Callsite] = { - val requests = selectCallsitesForInlining + private def collectAndOrderInlineRequests: List[InlineRequest] = { + val requestsByMethod = selectCallsitesForInlining withDefaultValue Set.empty + + val elided = mutable.Set.empty[InlineRequest] + def nonElidedRequests(methodNode: MethodNode): Set[InlineRequest] = requestsByMethod(methodNode) diff elided - // This map is an index to look up the inlining requests for a method. The value sets are mutable - // to allow removing elided requests (to break inlining cycles). The map itself is mutable to - // allow efficient building: requests.groupBy would build values as List[Callsite] that need to - // be transformed to mutable sets. - val inlineRequestsForMethod: mutable.Map[MethodNode, mutable.Set[Callsite]] = mutable.HashMap.empty.withDefaultValue(mutable.HashSet.empty) - for (r <- requests) inlineRequestsForMethod.getOrElseUpdate(r.callsiteMethod, mutable.HashSet.empty) += r + def allCallees(r: InlineRequest): Set[MethodNode] = r.post.flatMap(allCallees).toSet + r.callsite.callee.get.callee /** * Break cycles in the inline request graph by removing callsites. @@ -254,236 +174,454 @@ class Inliner[BT <: BTypes](val btypes: BT) { * The list `requests` is traversed left-to-right, removing those callsites that are part of a * cycle. Elided callsites are also removed from the `inlineRequestsForMethod` map. */ - def breakInlineCycles(requests: List[Callsite]): List[Callsite] = { + def breakInlineCycles: List[InlineRequest] = { // is there a path of inline requests from start to goal? - def isReachable(start: MethodNode, goal: MethodNode): Boolean = { - @tailrec def reachableImpl(check: List[MethodNode], visited: Set[MethodNode]): Boolean = check match { - case x :: xs => + def isReachable(start: Set[MethodNode], goal: MethodNode): Boolean = { + @tailrec def reachableImpl(check: Set[MethodNode], visited: Set[MethodNode]): Boolean = { + if (check.isEmpty) false + else { + val x = check.head if (x == goal) true - else if (visited(x)) reachableImpl(xs, visited) + else if (visited(x)) reachableImpl(check - x, visited) else { - val callees = inlineRequestsForMethod(x).map(_.callee.get.callee) - reachableImpl(xs ::: callees.toList, visited + x) + val callees = nonElidedRequests(x).flatMap(allCallees) + reachableImpl(check - x ++ callees, visited + x) } - - case Nil => - false + } } - reachableImpl(List(start), Set.empty) + reachableImpl(start, Set.empty) } - val result = new mutable.ListBuffer[Callsite]() + val result = new mutable.ListBuffer[InlineRequest]() + val requests = requestsByMethod.valuesIterator.flatten.toArray // sort the inline requests to ensure that removing requests is deterministic - for (r <- requests.sorted(callsiteOrdering)) { + java.util.Arrays.sort(requests, callsiteOrdering) + for (r <- requests) { // is there a chain of inlining requests that would inline the callsite method into the callee? - if (isReachable(r.callee.get.callee, r.callsiteMethod)) - inlineRequestsForMethod(r.callsiteMethod) -= r + if (isReachable(allCallees(r), r.callsite.callsiteMethod)) + elided += r else result += r + () } result.toList } // sort the remaining inline requests such that the leaves appear first, then those requests // that become leaves, etc. - def leavesFirst(requests: List[Callsite], visited: Set[Callsite] = Set.empty): List[Callsite] = { + def leavesFirst(requests: List[InlineRequest], visited: Set[InlineRequest] = Set.empty): List[InlineRequest] = { if (requests.isEmpty) Nil else { val (leaves, others) = requests.partition(r => { - val inlineRequestsForCallee = inlineRequestsForMethod(r.callee.get.callee) - inlineRequestsForCallee.forall(visited) + val inlineRequestsForCallees = allCallees(r).flatMap(nonElidedRequests) + inlineRequestsForCallees.forall(visited) }) assert(leaves.nonEmpty, requests) leaves ::: leavesFirst(others, visited ++ leaves) } } - leavesFirst(breakInlineCycles(requests)) + leavesFirst(breakInlineCycles) } - /** - * Copy and adapt the instructions of a method to a callsite. + * Given an InlineRequest(mainCallsite, post = List(postCallsite)), the postCallsite is a callsite + * in the method `mainCallsite.callee`. Once the mainCallsite is inlined into the target method + * (mainCallsite.callsiteMethod), we need to find the cloned callsite that corresponds to the + * postCallsite so we can inline that into the target method as well. * - * Preconditions: - * - The maxLocals and maxStack values of the callsite method are correctly computed - * - The callsite method contains no unreachable basic blocks, i.e., running an [[Analyzer]] - * does not produce any `null` frames + * However, it is possible that there is no cloned callsite at all that corresponds to the + * postCallsite, for example if the corresponding callsite already inlined. Example: + * + * def a() = 1 + * def b() = a() + 2 + * def c() = b() + 3 + * def d() = c() + 4 + * + * We have the following callsite objects in the call graph: + * + * c1 = a() in b + * c2 = b() in c + * c3 = c() in d * - * @param callsiteInstruction The invocation instruction - * @param callsiteStackHeight The stack height at the callsite - * @param callsiteMethod The method in which the invocation occurs - * @param callsiteClass The class in which the callsite method is defined - * @param callee The invoked method - * @param calleeDeclarationClass The class in which the invoked method is defined - * @param receiverKnownNotNull `true` if the receiver is known to be non-null - * @param keepLineNumbers `true` if LineNumberNodes should be copied to the call site - * @return `Some(message)` if inlining cannot be performed, `None` otherwise + * Assume we have the following inline request + * r = InlineRequest(c3, + * post = List(InlineRequest(c2, + * post = List(InlineRequest(c1, post = Nil))))) + * + * But before inlining r, assume a separate InlineRequest(c2, post = Nil) is inlined first. We get + * + * c1' = a() in c // added to the call graph + * c1.inlinedClones += (c1' at c2) // remember that c1' was created when inlining c2 + * ~c2~ // c2 is removed from the call graph + * + * If we now inline r, we first inline c3. We get + * + * c1'' = a() in d // added to call graph + * c1'.inlinedClones += (c1'' at c3) // remember that c1'' was created when inlining c3 + * ~c3~ + * + * Now we continue with the post-requests for r, i.e. c2. + * - we try to find the clone of c2 that was created when inlining c3 - but there is none. c2 + * was already inlined before + * - we continue with the post-request of c2: c1 + * - we search for the callsite of c1 that was cloned when inlining c2, we find c1' + * - recursively we search for the callsite of c1' that was cloned when inlining c3, we find c1'' + * - so we create an inline request for c1'' */ - def inline(callsiteInstruction: MethodInsnNode, callsiteStackHeight: Int, callsiteMethod: MethodNode, callsiteClass: ClassBType, - callee: MethodNode, calleeDeclarationClass: ClassBType, - receiverKnownNotNull: Boolean, keepLineNumbers: Boolean): Option[CannotInlineWarning] = { - canInline(callsiteInstruction, callsiteStackHeight, callsiteMethod, callsiteClass, callee, calleeDeclarationClass) orElse { - // New labels for the cloned instructions - val labelsMap = cloneLabels(callee) - val (clonedInstructions, instructionMap) = cloneInstructions(callee, labelsMap) - if (!keepLineNumbers) { - removeLineNumberNodes(clonedInstructions) + def adaptPostRequestForMainCallsite(post: InlineRequest, mainCallsite: Callsite): List[InlineRequest] = { + def impl(post: InlineRequest, at: Callsite): List[InlineRequest] = { + post.callsite.inlinedClones.find(_.clonedWhenInlining == at) match { + case Some(clonedCallsite) => + List(InlineRequest(clonedCallsite.callsite, post.post, post.reason)) + case None => + post.post.flatMap(impl(_, post.callsite)).flatMap(impl(_, at)) } + } + impl(post, mainCallsite) + } + + class UndoLog(active: Boolean = true) { + import java.util.{ ArrayList => JArrayList } + + private var actions = List.empty[() => Unit] + private var methodStateSaved = false + + def apply(a: => Unit): Unit = if (active) actions = (() => a) :: actions + def rollback(): Unit = if (active) actions.foreach(_.apply()) - // local vars in the callee are shifted by the number of locals at the callsite - val localVarShift = callsiteMethod.maxLocals - clonedInstructions.iterator.asScala foreach { - case varInstruction: VarInsnNode => varInstruction.`var` += localVarShift - case iinc: IincInsnNode => iinc.`var` += localVarShift - case _ => () + def saveMethodState(methodNode: MethodNode): Unit = if (active && !methodStateSaved) { + methodStateSaved = true + val currentInstructions = methodNode.instructions.toArray + val currentLocalVariables = new JArrayList(methodNode.localVariables) + val currentTryCatchBlocks = new JArrayList(methodNode.tryCatchBlocks) + val currentMaxLocals = methodNode.maxLocals + val currentMaxStack = methodNode.maxStack + + apply { + // `methodNode.instructions.clear()` doesn't work: it keeps the `prev` / `next` / `index` of + // instruction nodes. `instructions.removeAll(true)` would work, but is not public. + methodNode.instructions.iterator.asScala.toList.foreach(methodNode.instructions.remove) + for (i <- currentInstructions) methodNode.instructions.add(i) + + methodNode.localVariables.clear() + methodNode.localVariables.addAll(currentLocalVariables) + + methodNode.tryCatchBlocks.clear() + methodNode.tryCatchBlocks.addAll(currentTryCatchBlocks) + + methodNode.maxLocals = currentMaxLocals + methodNode.maxStack = currentMaxStack } + } + } - // add a STORE instruction for each expected argument, including for THIS instance if any - val argStores = new InsnList - var nextLocalIndex = callsiteMethod.maxLocals - if (!isStaticMethod(callee)) { - if (!receiverKnownNotNull) { - argStores.add(new InsnNode(DUP)) - val nonNullLabel = newLabelNode - argStores.add(new JumpInsnNode(IFNONNULL, nonNullLabel)) - argStores.add(new InsnNode(ACONST_NULL)) - argStores.add(new InsnNode(ATHROW)) - argStores.add(nonNullLabel) + val NoUndoLogging = new UndoLog(active = false) + + /** + * Inline the callsite of an inlining request and its post-inlining requests. + * + * @return An inliner warning for each callsite that could not be inlined. + */ + def inline(request: InlineRequest, undo: UndoLog = NoUndoLogging): List[CannotInlineWarning] = { + def doInline(undo: UndoLog, callRollback: Boolean = false): List[CannotInlineWarning] = { + InlineLog.withInlineLogging(request) { + inlineCallsite(request.callsite, undo) + } { + val postRequests = request.post.flatMap(adaptPostRequestForMainCallsite(_, request.callsite)) + val warnings = postRequests.flatMap(inline(_, undo)) + if (callRollback && warnings.nonEmpty) { + undo.rollback() + InlineLog(InlineLogRollback(request, warnings)) } - argStores.add(new VarInsnNode(ASTORE, nextLocalIndex)) - nextLocalIndex += 1 + warnings } + } - // We just use an asm.Type here, no need to create the MethodBType. - val calleAsmType = asm.Type.getMethodType(callee.desc) + def inlinedByPost(insns: List[AbstractInsnNode]): Boolean = + insns.nonEmpty && insns.forall(ins => request.post.exists(_.callsite.callsiteInstruction == ins)) - for(argTp <- calleAsmType.getArgumentTypes) { - val opc = argTp.getOpcode(ISTORE) // returns the correct xSTORE instruction for argTp - argStores.insert(new VarInsnNode(opc, nextLocalIndex)) // "insert" is "prepend" - the last argument is on the top of the stack - nextLocalIndex += argTp.getSize + canInlineCallsite(request.callsite) match { + case None => + doInline(undo) + + case Some((_, illegalAccessInsns)) if inlinedByPost(illegalAccessInsns) => + // speculatively inline, roll back if an illegalAccessInsn cannot be eliminated + if (undo == NoUndoLogging) doInline(new UndoLog(), callRollback = true) + else doInline(undo) + + case Some((w, _)) => + InlineLog(InlineLogFail(request, w)) + List(w) + } + } + + /** + * Copy and adapt the instructions of a method to a callsite. + * + * Preconditions: + * - The callsite can safely be inlined (canInlineBody is true) + * - The maxLocals and maxStack values of the callsite method are correctly computed + * + * @return A map associating instruction nodes of the callee with the corresponding cloned + * instruction in the callsite method. + */ + def inlineCallsite(callsite: Callsite, undo: UndoLog = NoUndoLogging): Unit = { + import callsite.{callsiteClass, callsiteMethod, callsiteInstruction, receiverKnownNotNull, callsiteStackHeight} + val Right(callsiteCallee) = callsite.callee + import callsiteCallee.{callee, calleeDeclarationClass, sourceFilePath} + + // Inlining requires the callee not to have unreachable code, the analyzer used below should not + // return any `null` frames. Note that inlining a method can create unreachable code. Example: + // def f = throw e + // def g = f; println() // println is unreachable after inlining f + // If we have an inline request for a call to g, and f has been already inlined into g, we + // need to run DCE on g's body before inlining g. + localOpt.minimalRemoveUnreachableCode(callee, calleeDeclarationClass.internalName) + + // If the callsite was eliminated by DCE, do nothing. + if (!callGraph.containsCallsite(callsite)) return + + // New labels for the cloned instructions + val labelsMap = cloneLabels(callee) + val sameSourceFile = sourceFilePath match { + case Some(calleeSource) => byteCodeRepository.compilingClasses.get(callsiteClass.internalName) match { + case Some((_, `calleeSource`)) => true + case _ => false } + case _ => false + } + val (clonedInstructions, instructionMap, targetHandles) = cloneInstructions(callee, labelsMap, keepLineNumbers = sameSourceFile) + + // local vars in the callee are shifted by the number of locals at the callsite + val localVarShift = callsiteMethod.maxLocals + clonedInstructions.iterator.asScala foreach { + case varInstruction: VarInsnNode => varInstruction.`var` += localVarShift + case iinc: IincInsnNode => iinc.`var` += localVarShift + case _ => () + } - clonedInstructions.insert(argStores) - - // label for the exit of the inlined functions. xRETURNs are replaced by GOTOs to this label. - val postCallLabel = newLabelNode - clonedInstructions.add(postCallLabel) - - // replace xRETURNs: - // - store the return value (if any) - // - clear the stack of the inlined method (insert DROPs) - // - load the return value - // - GOTO postCallLabel - - val returnType = calleAsmType.getReturnType - val hasReturnValue = returnType.getSort != asm.Type.VOID - val returnValueIndex = callsiteMethod.maxLocals + callee.maxLocals - nextLocalIndex += returnType.getSize - - def returnValueStore(returnInstruction: AbstractInsnNode) = { - val opc = returnInstruction.getOpcode match { - case IRETURN => ISTORE - case LRETURN => LSTORE - case FRETURN => FSTORE - case DRETURN => DSTORE - case ARETURN => ASTORE - } - new VarInsnNode(opc, returnValueIndex) + // add a STORE instruction for each expected argument, including for THIS instance if any + val argStores = new InsnList + var nextLocalIndex = callsiteMethod.maxLocals + if (!isStaticMethod(callee)) { + if (!receiverKnownNotNull) { + argStores.add(new InsnNode(DUP)) + val nonNullLabel = newLabelNode + argStores.add(new JumpInsnNode(IFNONNULL, nonNullLabel)) + argStores.add(new InsnNode(ACONST_NULL)) + argStores.add(new InsnNode(ATHROW)) + argStores.add(nonNullLabel) } + argStores.add(new VarInsnNode(ASTORE, nextLocalIndex)) + nextLocalIndex += 1 + } - // We run an interpreter to know the stack height at each xRETURN instruction and the sizes - // of the values on the stack. - val analyzer = new AsmAnalyzer(callee, calleeDeclarationClass.internalName) + // We just use an asm.Type here, no need to create the MethodBType. + val calleAsmType = asm.Type.getMethodType(callee.desc) + val calleeParamTypes = calleAsmType.getArgumentTypes - for (originalReturn <- callee.instructions.iterator().asScala if isReturn(originalReturn)) { - val frame = analyzer.frameAt(originalReturn) - var stackHeight = frame.getStackSize + for(argTp <- calleeParamTypes) { + val opc = argTp.getOpcode(ISTORE) // returns the correct xSTORE instruction for argTp + argStores.insert(new VarInsnNode(opc, nextLocalIndex)) // "insert" is "prepend" - the last argument is on the top of the stack + nextLocalIndex += argTp.getSize + } - val inlinedReturn = instructionMap(originalReturn) - val returnReplacement = new InsnList + clonedInstructions.insert(argStores) + + // label for the exit of the inlined functions. xRETURNs are replaced by GOTOs to this label. + val postCallLabel = newLabelNode + clonedInstructions.add(postCallLabel) + + // replace xRETURNs: + // - store the return value (if any) + // - clear the stack of the inlined method (insert DROPs) + // - load the return value + // - GOTO postCallLabel + + val returnType = calleAsmType.getReturnType + val hasReturnValue = returnType.getSort != asm.Type.VOID + val returnValueIndex = callsiteMethod.maxLocals + callee.maxLocals + nextLocalIndex += returnType.getSize + + def returnValueStore(returnInstruction: AbstractInsnNode) = { + val opc = returnInstruction.getOpcode match { + case IRETURN => ISTORE + case LRETURN => LSTORE + case FRETURN => FSTORE + case DRETURN => DSTORE + case ARETURN => ASTORE + } + new VarInsnNode(opc, returnValueIndex) + } - def drop(slot: Int) = returnReplacement add getPop(frame.peekStack(slot).getSize) + // We run an interpreter to know the stack height at each xRETURN instruction and the sizes + // of the values on the stack. + // We don't need to worry about the method being too large for running an analysis. Callsites of + // large methods are not added to the call graph. + val analyzer = new AsmAnalyzer(callee, calleeDeclarationClass.internalName) - // for non-void methods, store the stack top into the return local variable - if (hasReturnValue) { - returnReplacement add returnValueStore(originalReturn) - stackHeight -= 1 - } + for (originalReturn <- callee.instructions.iterator().asScala if isReturn(originalReturn)) { + val frame = analyzer.frameAt(originalReturn) + var stackHeight = frame.getStackSize - // drop the rest of the stack - for (i <- 0 until stackHeight) drop(i) + val inlinedReturn = instructionMap(originalReturn) + val returnReplacement = new InsnList - returnReplacement add new JumpInsnNode(GOTO, postCallLabel) - clonedInstructions.insert(inlinedReturn, returnReplacement) - clonedInstructions.remove(inlinedReturn) - } + def drop(slot: Int) = returnReplacement add getPop(frame.peekStack(slot).getSize) - // Load instruction for the return value + // for non-void methods, store the stack top into the return local variable if (hasReturnValue) { - val retVarLoad = { - val opc = returnType.getOpcode(ILOAD) - new VarInsnNode(opc, returnValueIndex) - } - clonedInstructions.insert(postCallLabel, retVarLoad) + returnReplacement add returnValueStore(originalReturn) + stackHeight -= 1 } - callsiteMethod.instructions.insert(callsiteInstruction, clonedInstructions) - callsiteMethod.instructions.remove(callsiteInstruction) - - callsiteMethod.localVariables.addAll(cloneLocalVariableNodes(callee, labelsMap, callee.name + "_").asJava) - callsiteMethod.tryCatchBlocks.addAll(cloneTryCatchBlockNodes(callee, labelsMap).asJava) - - // Add all invocation instructions and closure instantiations that were inlined to the call graph - callee.instructions.iterator().asScala foreach { - case originalCallsiteIns: MethodInsnNode => - callGraph.callsites.get(originalCallsiteIns) match { - case Some(originalCallsite) => - val newCallsiteIns = instructionMap(originalCallsiteIns).asInstanceOf[MethodInsnNode] - callGraph.callsites(newCallsiteIns) = Callsite( - callsiteInstruction = newCallsiteIns, - callsiteMethod = callsiteMethod, - callsiteClass = callsiteClass, - callee = originalCallsite.callee, - argInfos = Nil, // TODO: re-compute argInfos for new destination (once we actually compute them) - callsiteStackHeight = callsiteStackHeight + originalCallsite.callsiteStackHeight, - receiverKnownNotNull = originalCallsite.receiverKnownNotNull, - callsitePosition = originalCallsite.callsitePosition - ) - - case None => - } + // drop the rest of the stack + for (i <- 0 until stackHeight) drop(i) - case indy: InvokeDynamicInsnNode => - callGraph.closureInstantiations.get(indy) match { - case Some(closureInit) => - val newIndy = instructionMap(indy).asInstanceOf[InvokeDynamicInsnNode] - callGraph.closureInstantiations(newIndy) = ClosureInstantiation(closureInit.lambdaMetaFactoryCall.copy(indy = newIndy), callsiteMethod, callsiteClass) - - case None => - } + returnReplacement add new JumpInsnNode(GOTO, postCallLabel) + clonedInstructions.insert(inlinedReturn, returnReplacement) + clonedInstructions.remove(inlinedReturn) + } - case _ => + // Load instruction for the return value + if (hasReturnValue) { + val retVarLoad = { + val opc = returnType.getOpcode(ILOAD) + new VarInsnNode(opc, returnValueIndex) } - // Remove the elided invocation from the call graph - callGraph.callsites.remove(callsiteInstruction) + clonedInstructions.insert(postCallLabel, retVarLoad) + } - // Inlining a method body can render some code unreachable, see example above (in runInliner). - unreachableCodeEliminated -= callsiteMethod + undo.saveMethodState(callsiteMethod) - callsiteMethod.maxLocals += returnType.getSize + callee.maxLocals - callsiteMethod.maxStack = math.max(callsiteMethod.maxStack, callee.maxStack + callsiteStackHeight) + callsiteMethod.instructions.insert(callsiteInstruction, clonedInstructions) + callsiteMethod.instructions.remove(callsiteInstruction) - None + callsiteMethod.localVariables.addAll(cloneLocalVariableNodes(callee, labelsMap, callee.name, localVarShift).asJava) + // prepend the handlers of the callee. the order of handlers matters: when an exception is thrown + // at some instruction, the first handler guarding that instruction and having a matching exception + // type is executed. prepending the callee's handlers makes sure to test those handlers first if + // an exception is thrown in the inlined code. + callsiteMethod.tryCatchBlocks.addAll(0, cloneTryCatchBlockNodes(callee, labelsMap).asJava) + + callsiteMethod.maxLocals += returnType.getSize + callee.maxLocals + val maxStackOfInlinedCode = { + // One slot per value is correct for long / double, see comment in the `analysis` package object. + val numStoredArgs = calleeParamTypes.length + (if (isStaticMethod(callee)) 0 else 1) + callee.maxStack + callsiteStackHeight - numStoredArgs + } + val stackHeightAtNullCheck = { + // When adding a null check for the receiver, a DUP is inserted, which might cause a new maxStack. + // If the callsite has other argument values than the receiver on the stack, these are pop'ed + // and stored into locals before the null check, so in that case the maxStack doesn't grow. + val stackSlotForNullCheck = if (!isStaticMethod(callee) && !receiverKnownNotNull && calleeParamTypes.isEmpty) 1 else 0 + callsiteStackHeight + stackSlotForNullCheck } + + callsiteMethod.maxStack = math.max(callsiteMethod.maxStack, math.max(stackHeightAtNullCheck, maxStackOfInlinedCode)) + + val added = addIndyLambdaImplMethod(callsiteClass.internalName, targetHandles) + undo { removeIndyLambdaImplMethod(callsiteClass.internalName, added) } + + callGraph.addIfMissing(callee, calleeDeclarationClass) + + def mapArgInfo(argInfo: (Int, ArgInfo)): Option[(Int, ArgInfo)] = argInfo match { + case lit @ (_, FunctionLiteral) => Some(lit) + case (argIndex, ForwardedParam(paramIndex)) => callsite.argInfos.get(paramIndex).map((argIndex, _)) + } + + // Add all invocation instructions and closure instantiations that were inlined to the call graph + callGraph.callsites(callee).valuesIterator foreach { originalCallsite => + val newCallsiteIns = instructionMap(originalCallsite.callsiteInstruction).asInstanceOf[MethodInsnNode] + val argInfos = originalCallsite.argInfos flatMap mapArgInfo + val newCallsite = originalCallsite.copy( + callsiteInstruction = newCallsiteIns, + callsiteMethod = callsiteMethod, + callsiteClass = callsiteClass, + argInfos = argInfos, + callsiteStackHeight = callsiteStackHeight + originalCallsite.callsiteStackHeight + ) + val clonedCallsite = ClonedCallsite(newCallsite, callsite) + originalCallsite.inlinedClones += clonedCallsite + callGraph.addCallsite(newCallsite) + undo { + originalCallsite.inlinedClones -= clonedCallsite + callGraph.removeCallsite(newCallsite.callsiteInstruction, newCallsite.callsiteMethod) + } + } + + callGraph.closureInstantiations(callee).valuesIterator foreach { originalClosureInit => + val newIndy = instructionMap(originalClosureInit.lambdaMetaFactoryCall.indy).asInstanceOf[InvokeDynamicInsnNode] + val capturedArgInfos = originalClosureInit.capturedArgInfos flatMap mapArgInfo + val newClosureInit = ClosureInstantiation( + originalClosureInit.lambdaMetaFactoryCall.copy(indy = newIndy), + callsiteMethod, + callsiteClass, + capturedArgInfos) + originalClosureInit.inlinedClones += newClosureInit + callGraph.addClosureInstantiation(newClosureInit) + undo { + callGraph.removeClosureInstantiation(newClosureInit.lambdaMetaFactoryCall.indy, newClosureInit.ownerMethod) + } + } + + // Remove the elided invocation from the call graph + callGraph.removeCallsite(callsiteInstruction, callsiteMethod) + undo { callGraph.addCallsite(callsite) } + + // Inlining a method body can render some code unreachable, see example above in this method. + unreachableCodeEliminated -= callsiteMethod } /** - * Check whether an inling can be performed. Parmeters are described in method [[inline]]. + * Check whether an inlining can be performed. This method performs tests that don't change even + * if the body of the callee is changed by the inliner / optimizer, so it can be used early + * (when looking at the call graph and collecting inline requests for the program). + * + * The tests that inspect the callee's instructions are implemented in method `canInlineBody`, + * which is queried when performing an inline. + * * @return `Some(message)` if inlining cannot be performed, `None` otherwise */ - def canInline(callsiteInstruction: MethodInsnNode, callsiteStackHeight: Int, callsiteMethod: MethodNode, callsiteClass: ClassBType, - callee: MethodNode, calleeDeclarationClass: ClassBType): Option[CannotInlineWarning] = { + def earlyCanInlineCheck(callsite: Callsite): Option[CannotInlineWarning] = { + import callsite.{callsiteMethod, callsiteClass} + val Right(callsiteCallee) = callsite.callee + import callsiteCallee.{callee, calleeDeclarationClass} + + if (isSynchronizedMethod(callee)) { + // Could be done by locking on the receiver, wrapping the inlined code in a try and unlocking + // in finally. But it's probably not worth the effort, scala never emits synchronized methods. + Some(SynchronizedMethod(calleeDeclarationClass.internalName, callee.name, callee.desc, callsite.isInlineAnnotated)) + } else if (isStrictfpMethod(callsiteMethod) != isStrictfpMethod(callee)) { + Some(StrictfpMismatch( + calleeDeclarationClass.internalName, callee.name, callee.desc, callsite.isInlineAnnotated, + callsiteClass.internalName, callsiteMethod.name, callsiteMethod.desc)) + } else + None + } + + /** + * Check whether the body of the callee contains any instructions that prevent the callsite from + * being inlined. See also method `earlyCanInlineCheck`. + * + * The result of this check depends on changes to the callee method's body. For example, if the + * callee initially invokes a private method, it cannot be inlined into a different class. If the + * private method is inlined into the callee, inlining the callee becomes possible. Therefore + * we don't query it while traversing the call graph and selecting callsites to inline - it might + * rule out callsites that can be inlined just fine. + * + * Returns + * - `None` if the callsite can be inlined + * - `Some((message, Nil))` if there was an issue performing the access checks, for example + * because of a missing classfile + * - `Some((message, instructions))` if inlining `instructions` into the callsite method would + * cause an IllegalAccessError + */ + def canInlineCallsite(callsite: Callsite): Option[(CannotInlineWarning, List[AbstractInsnNode])] = { + import callsite.{callsiteInstruction, callsiteMethod, callsiteClass, callsiteStackHeight} + val Right(callsiteCallee) = callsite.callee + import callsiteCallee.{callee, calleeDeclarationClass} def calleeDesc = s"${callee.name} of type ${callee.desc} in ${calleeDeclarationClass.internalName}" def methodMismatch = s"Wrong method node for inlining ${textify(callsiteInstruction)}: $calleeDesc" @@ -511,31 +649,30 @@ class Inliner[BT <: BTypes](val btypes: BT) { } if (codeSizeOKForInlining(callsiteMethod, callee)) { - Some(ResultingMethodTooLarge( - calleeDeclarationClass.internalName, callee.name, callee.desc, - callsiteClass.internalName, callsiteMethod.name, callsiteMethod.desc)) - } else if (isSynchronizedMethod(callee)) { - // Could be done by locking on the receiver, wrapping the inlined code in a try and unlocking - // in finally. But it's probably not worth the effort, scala never emits synchronized methods. - Some(SynchronizedMethod(calleeDeclarationClass.internalName, callee.name, callee.desc)) - } else if (isStrictfpMethod(callsiteMethod) != isStrictfpMethod(callee)) { - Some(StrictfpMismatch( - calleeDeclarationClass.internalName, callee.name, callee.desc, - callsiteClass.internalName, callsiteMethod.name, callsiteMethod.desc)) + val warning = ResultingMethodTooLarge( + calleeDeclarationClass.internalName, callee.name, callee.desc, callsite.isInlineAnnotated, + callsiteClass.internalName, callsiteMethod.name, callsiteMethod.desc) + Some((warning, Nil)) } else if (!callee.tryCatchBlocks.isEmpty && stackHasNonParameters) { - Some(MethodWithHandlerCalledOnNonEmptyStack( - calleeDeclarationClass.internalName, callee.name, callee.desc, - callsiteClass.internalName, callsiteMethod.name, callsiteMethod.desc)) - } else findIllegalAccess(callee.instructions, calleeDeclarationClass, callsiteClass) map { - case (illegalAccessIns, None) => - IllegalAccessInstruction( - calleeDeclarationClass.internalName, callee.name, callee.desc, - callsiteClass.internalName, illegalAccessIns) - - case (illegalAccessIns, Some(warning)) => - IllegalAccessCheckFailed( - calleeDeclarationClass.internalName, callee.name, callee.desc, - callsiteClass.internalName, illegalAccessIns, warning) + val warning = MethodWithHandlerCalledOnNonEmptyStack( + calleeDeclarationClass.internalName, callee.name, callee.desc, callsite.isInlineAnnotated, + callsiteClass.internalName, callsiteMethod.name, callsiteMethod.desc) + Some((warning, Nil)) + } else findIllegalAccess(callee.instructions, calleeDeclarationClass, callsiteClass) match { + case Right(Nil) => + None + + case Right(illegalAccessInsns) => + val warning = IllegalAccessInstruction( + calleeDeclarationClass.internalName, callee.name, callee.desc, callsite.isInlineAnnotated, + callsiteClass.internalName, illegalAccessInsns.head) + Some((warning, illegalAccessInsns)) + + case Left((illegalAccessIns, cause)) => + val warning = IllegalAccessCheckFailed( + calleeDeclarationClass.internalName, callee.name, callee.desc, callsite.isInlineAnnotated, + callsiteClass.internalName, illegalAccessIns, cause) + Some((warning, Nil)) } } @@ -545,7 +682,7 @@ class Inliner[BT <: BTypes](val btypes: BT) { * (A2) C and D are members of the same run-time package */ def classIsAccessible(accessed: BType, from: ClassBType): Either[OptimizerWarning, Boolean] = (accessed: @unchecked) match { - // TODO: A2 requires "same run-time package", which seems to be package + classloader (JMVS 5.3.). is the below ok? + // TODO: A2 requires "same run-time package", which seems to be package + classloader (JVMS 5.3.). is the below ok? case c: ClassBType => c.isPublic.map(_ || c.packageInternalName == from.packageInternalName) case a: ArrayBType => classIsAccessible(a.elementType, from) case _: PrimitiveBType => Right(true) @@ -587,7 +724,7 @@ class Inliner[BT <: BTypes](val btypes: BT) { * type from there (https://github.com/scala-opt/scala/issues/13). */ def memberIsAccessible(memberFlags: Int, memberDeclClass: ClassBType, memberRefClass: ClassBType, from: ClassBType): Either[OptimizerWarning, Boolean] = { - // TODO: B3 requires "same run-time package", which seems to be package + classloader (JMVS 5.3.). is the below ok? + // TODO: B3 requires "same run-time package", which seems to be package + classloader (JVMS 5.3.). is the below ok? def samePackageAsDestination = memberDeclClass.packageInternalName == from.packageInternalName def targetObjectConformsToDestinationClass = false // needs type propagation analysis, see above @@ -624,13 +761,14 @@ class Inliner[BT <: BTypes](val btypes: BT) { } /** - * Returns the first instruction in the `instructions` list that would cause a - * [[java.lang.IllegalAccessError]] when inlined into the `destinationClass`. - * - * If validity of some instruction could not be checked because an error occurred, the instruction - * is returned together with a warning message that describes the problem. + * Returns + * - `Right(Nil)` if all instructions can be safely inlined + * - `Right(insns)` if inlining any of `insns` would cause a [[java.lang.IllegalAccessError]] + * when inlined into the `destinationClass` + * - `Left((insn, warning))` if validity of some instruction could not be checked because an + * error occurred */ - def findIllegalAccess(instructions: InsnList, calleeDeclarationClass: ClassBType, destinationClass: ClassBType): Option[(AbstractInsnNode, Option[OptimizerWarning])] = { + def findIllegalAccess(instructions: InsnList, calleeDeclarationClass: ClassBType, destinationClass: ClassBType): Either[(AbstractInsnNode, OptimizerWarning), List[AbstractInsnNode]] = { /** * Check if `instruction` can be transplanted to `destinationClass`. * @@ -759,17 +897,15 @@ class Inliner[BT <: BTypes](val btypes: BT) { } val it = instructions.iterator.asScala - @tailrec def find: Option[(AbstractInsnNode, Option[OptimizerWarning])] = { - if (!it.hasNext) None // all instructions are legal - else { - val i = it.next() - isLegal(i) match { - case Left(warning) => Some((i, Some(warning))) // checking isLegal for i failed - case Right(false) => Some((i, None)) // an illegal instruction was found - case _ => find - } + val illegalAccess = mutable.ListBuffer.empty[AbstractInsnNode] + while (it.hasNext) { + val i = it.next() + isLegal(i) match { + case Left(warning) => return Left((i, warning)) // checking isLegal for i failed + case Right(false) => illegalAccess += i // an illegal instruction was found + case _ => } } - find + Right(illegalAccess.toList) } } diff --git a/src/compiler/scala/tools/nsc/backend/jvm/opt/InlinerHeuristics.scala b/src/compiler/scala/tools/nsc/backend/jvm/opt/InlinerHeuristics.scala new file mode 100644 index 0000000000..63360e17ff --- /dev/null +++ b/src/compiler/scala/tools/nsc/backend/jvm/opt/InlinerHeuristics.scala @@ -0,0 +1,339 @@ +/* NSC -- new Scala compiler + * Copyright 2005-2014 LAMP/EPFL + * @author Martin Odersky + */ + +package scala.tools.nsc +package backend.jvm +package opt + +import scala.annotation.tailrec +import scala.collection.JavaConverters._ +import scala.tools.asm.Opcodes +import scala.tools.asm.tree.{AbstractInsnNode, MethodInsnNode, MethodNode} +import scala.tools.nsc.backend.jvm.BTypes.InternalName +import scala.tools.nsc.backend.jvm.BackendReporting.{CalleeNotFinal, OptimizerWarning} + +class InlinerHeuristics[BT <: BTypes](val bTypes: BT) { + import bTypes._ + import callGraph._ + + final case class InlineRequest(callsite: Callsite, post: List[InlineRequest], reason: String) { + // invariant: all post inline requests denote callsites in the callee of the main callsite + for (pr <- post) assert(pr.callsite.callsiteMethod == callsite.callee.get.callee, s"Callsite method mismatch: main $callsite - post ${pr.callsite}") + } + + def canInlineFromSource(sourceFilePath: Option[String]) = compilerSettings.optInlineGlobal || sourceFilePath.isDefined + + /** + * Select callsites from the call graph that should be inlined, grouped by the containing method. + * Cyclic inlining requests are allowed, the inliner will eliminate requests to break cycles. + */ + def selectCallsitesForInlining: Map[MethodNode, Set[InlineRequest]] = { + // We should only create inlining requests for callsites being compiled (not for callsites in + // classes on the classpath). The call graph may contain callsites of classes parsed from the + // classpath. In order to get only the callsites being compiled, we start at the map of + // compilingClasses in the byteCodeRepository. + val compilingMethods = for { + (classNode, _) <- byteCodeRepository.compilingClasses.valuesIterator + methodNode <- classNode.methods.iterator.asScala + } yield methodNode + + compilingMethods.map(methodNode => { + var requests = Set.empty[InlineRequest] + callGraph.callsites(methodNode).valuesIterator foreach { + case callsite @ Callsite(_, _, _, Right(Callee(callee, _, _, _, _, _, _, callsiteWarning)), _, _, _, pos, _, _) => + inlineRequest(callsite, requests) match { + case Some(Right(req)) => requests += req + + case Some(Left(w)) => + if (w.emitWarning(compilerSettings)) { + backendReporting.inlinerWarning(callsite.callsitePosition, w.toString) + } + + case None => + if (callsiteWarning.isDefined && callsiteWarning.get.emitWarning(compilerSettings)) + backendReporting.inlinerWarning(pos, s"there was a problem determining if method ${callee.name} can be inlined: \n"+ callsiteWarning.get) + } + + case Callsite(ins, _, _, Left(warning), _, _, _, pos, _, _) => + if (warning.emitWarning(compilerSettings)) + backendReporting.inlinerWarning(pos, s"failed to determine if ${ins.name} should be inlined:\n$warning") + } + (methodNode, requests) + }).filterNot(_._2.isEmpty).toMap + } + + private def isTraitStaticSuperAccessorName(s: String) = s.endsWith("$") + private def traitStaticSuperAccessorName(s: String) = s + "$" + + private def isTraitSuperAccessor(method: MethodNode, owner: ClassBType): Boolean = { + owner.isInterface == Right(true) && BytecodeUtils.isStaticMethod(method) && isTraitStaticSuperAccessorName(method.name) + } + + private def findSingleCall(method: MethodNode, such: MethodInsnNode => Boolean): Option[MethodInsnNode] = { + @tailrec def noMoreInvoke(insn: AbstractInsnNode): Boolean = { + insn == null || (!insn.isInstanceOf[MethodInsnNode] && noMoreInvoke(insn.getNext)) + } + @tailrec def find(insn: AbstractInsnNode): Option[MethodInsnNode] = { + if (insn == null) None + else insn match { + case mi: MethodInsnNode => + if (such(mi) && noMoreInvoke(insn.getNext)) Some(mi) + else None + case _ => + find(insn.getNext) + } + } + find(method.instructions.getFirst) + } + private def superAccessorInvocation(method: MethodNode): Option[MethodInsnNode] = + findSingleCall(method, mi => mi.itf && mi.getOpcode == Opcodes.INVOKESTATIC && isTraitStaticSuperAccessorName(mi.name)) + + private def isMixinForwarder(method: MethodNode, owner: ClassBType): Boolean = { + owner.isInterface == Right(false) && + !BytecodeUtils.isStaticMethod(method) && + (superAccessorInvocation(method) match { + case Some(mi) => mi.name == traitStaticSuperAccessorName(method.name) + case _ => false + }) + } + + private def isTraitSuperAccessorOrMixinForwarder(method: MethodNode, owner: ClassBType): Boolean = { + isTraitSuperAccessor(method, owner) || isMixinForwarder(method, owner) + } + + + /** + * Returns the inline request for a callsite if the callsite should be inlined according to the + * current heuristics (`-Yopt-inline-heuristics`). + * + * The resulting inline request may contain post-inlining requests of callsites that in turn are + * also selected as individual inlining requests. + * + * @return `None` if this callsite should not be inlined according to the active heuristic + * `Some(Left)` if the callsite cannot be inlined (for example because that would cause + * an IllegalAccessError) but should be according to the heuristic + * TODO: what if a downstream inline request would cause an IAE and we don't create an + * InlineRequest for the original callsite? new subclass of OptimizerWarning. + * `Some(Right)` if the callsite should be and can be inlined + */ + def inlineRequest(callsite: Callsite, selectedRequestsForCallee: Set[InlineRequest]): Option[Either[OptimizerWarning, InlineRequest]] = { + def requestIfCanInline(callsite: Callsite, reason: String): Option[Either[OptimizerWarning, InlineRequest]] = { + val callee = callsite.callee.get + if (!callee.safeToInline) { + if (callsite.isInlineAnnotated && callee.canInlineFromSource) { + // By default, we only emit inliner warnings for methods annotated @inline. However, we don't + // want to be unnecessarily noisy with `-opt-warnings:_`: for example, the inliner heuristic + // would attempt to inline `Function1.apply$sp$II`, as it's higher-order (the receiver is + // a function), and it's concrete (forwards to `apply`). But because it's non-final, it cannot + // be inlined. So we only create warnings here for methods annotated @inline. + Some(Left(CalleeNotFinal( + callee.calleeDeclarationClass.internalName, + callee.callee.name, + callee.callee.desc, + callsite.isInlineAnnotated))) + } else None + } else inliner.earlyCanInlineCheck(callsite) match { + case Some(w) => Some(Left(w)) + case None => + val postInlineRequest: List[InlineRequest] = { + val postCall = + if (isTraitSuperAccessor(callee.callee, callee.calleeDeclarationClass)) { + // scala-dev#259: when inlining a trait super accessor, also inline the callsite to the default method + val implName = callee.callee.name.dropRight(1) + findSingleCall(callee.callee, mi => mi.itf && mi.getOpcode == Opcodes.INVOKESPECIAL && mi.name == implName) + } else { + // scala-dev#259: when inlining a mixin forwarder, also inline the callsite to the static super accessor + superAccessorInvocation(callee.callee) + } + postCall.flatMap(call => { + callGraph.addIfMissing(callee.callee, callee.calleeDeclarationClass) + val maybeCallsite = callGraph.findCallSite(callee.callee, call) + maybeCallsite.flatMap(requestIfCanInline(_, reason).flatMap(_.right.toOption)) + }).toList + } + Some(Right(InlineRequest(callsite, postInlineRequest, reason))) + } + } + + // scala-dev#259: don't inline into static accessors and mixin forwarders + if (isTraitSuperAccessorOrMixinForwarder(callsite.callsiteMethod, callsite.callsiteClass)) None + else { + val callee = callsite.callee.get + compilerSettings.YoptInlineHeuristics.value match { + case "everything" => + val reason = if (compilerSettings.YoptLogInline.isSetByUser) "the inline strategy is \"everything\"" else null + requestIfCanInline(callsite, reason) + + case "at-inline-annotated" => + def reason = if (!compilerSettings.YoptLogInline.isSetByUser) null else { + val what = if (callee.annotatedInline) "callee" else "callsite" + s"the $what is annotated `@inline`" + } + if (callsite.isInlineAnnotated && !callsite.isNoInlineAnnotated) requestIfCanInline(callsite, reason) + else None + + case "default" => + def reason = if (!compilerSettings.YoptLogInline.isSetByUser) null else { + if (callsite.isInlineAnnotated) { + val what = if (callee.annotatedInline) "callee" else "callsite" + s"the $what is annotated `@inline`" + } else { + val paramNames = Option(callee.callee.parameters).map(_.asScala.map(_.name).toVector) + def param(i: Int) = { + def syn = s"<param $i>" + paramNames.fold(syn)(v => v.applyOrElse(i, (_: Int) => syn)) + } + def samInfo(i: Int, sam: String, arg: String) = s"the argument for parameter (${param(i)}: $sam) is a $arg" + val argInfos = for ((i, sam) <- callee.samParamTypes; info <- callsite.argInfos.get(i)) yield { + val argKind = info match { + case FunctionLiteral => "function literal" + case ForwardedParam(_) => "parameter of the callsite method" + } + samInfo(i, sam.internalName.split('/').last, argKind) + } + s"the callee is a higher-order method, ${argInfos.mkString(", ")}" + } + } + def shouldInlineHO = callee.samParamTypes.nonEmpty && (callee.samParamTypes exists { + case (index, _) => callsite.argInfos.contains(index) + }) + if (!callsite.isNoInlineAnnotated && (callsite.isInlineAnnotated || shouldInlineHO)) requestIfCanInline(callsite, reason) + else None + } + } + } + + /* + // using http://lihaoyi.github.io/Ammonite/ + + load.ivy("com.google.guava" % "guava" % "18.0") + val javaUtilFunctionClasses = { + val rt = System.getProperty("sun.boot.class.path").split(":").find(_.endsWith("lib/rt.jar")).get + val u = new java.io.File(rt).toURL + val l = new java.net.URLClassLoader(Array(u)) + val cp = com.google.common.reflect.ClassPath.from(l) + cp.getTopLevelClasses("java.util.function").toArray.map(_.toString).toList + } + + // found using IntelliJ's "Find Usages" on the @FunctionalInterface annotation + val otherClasses = List( + "com.sun.javafx.css.parser.Recognizer", + "java.awt.KeyEventDispatcher", + "java.awt.KeyEventPostProcessor", + "java.io.FileFilter", + "java.io.FilenameFilter", + "java.lang.Runnable", + "java.lang.Thread$UncaughtExceptionHandler", + "java.nio.file.DirectoryStream$Filter", + "java.nio.file.PathMatcher", + "java.time.temporal.TemporalAdjuster", + "java.time.temporal.TemporalQuery", + "java.util.Comparator", + "java.util.concurrent.Callable", + "java.util.logging.Filter", + "java.util.prefs.PreferenceChangeListener", + "javafx.animation.Interpolatable", + "javafx.beans.InvalidationListener", + "javafx.beans.value.ChangeListener", + "javafx.collections.ListChangeListener", + "javafx.collections.MapChangeListener", + "javafx.collections.SetChangeListener", + "javafx.event.EventHandler", + "javafx.util.Builder", + "javafx.util.BuilderFactory", + "javafx.util.Callback" + ) + + val allClasses = javaUtilFunctionClasses ::: otherClasses + + load.ivy("org.ow2.asm" % "asm" % "5.0.4") + val classesAndSamNameDesc = allClasses.map(c => { + val cls = Class.forName(c) + val internalName = org.objectweb.asm.Type.getDescriptor(cls).drop(1).dropRight(1) // drop L and ; + val sams = cls.getMethods.filter(m => { + (m.getModifiers & java.lang.reflect.Modifier.ABSTRACT) != 0 && + m.getName != "equals" // Comparator has an abstract override of "equals" for adding Javadoc + }) + assert(sams.size == 1, internalName + sams.map(_.getName)) + val sam = sams.head + val samDesc = org.objectweb.asm.Type.getMethodDescriptor(sam) + (internalName, sam.getName, samDesc) + }) + println(classesAndSamNameDesc map { + case (cls, nme, desc) => s"""("$cls", "$nme$desc")""" + } mkString ("", ",\n", "\n")) + */ + private val javaSams: Map[String, String] = Map( + ("java/util/function/BiConsumer", "accept(Ljava/lang/Object;Ljava/lang/Object;)V"), + ("java/util/function/BiFunction", "apply(Ljava/lang/Object;Ljava/lang/Object;)Ljava/lang/Object;"), + ("java/util/function/BiPredicate", "test(Ljava/lang/Object;Ljava/lang/Object;)Z"), + ("java/util/function/BinaryOperator", "apply(Ljava/lang/Object;Ljava/lang/Object;)Ljava/lang/Object;"), + ("java/util/function/BooleanSupplier", "getAsBoolean()Z"), + ("java/util/function/Consumer", "accept(Ljava/lang/Object;)V"), + ("java/util/function/DoubleBinaryOperator", "applyAsDouble(DD)D"), + ("java/util/function/DoubleConsumer", "accept(D)V"), + ("java/util/function/DoubleFunction", "apply(D)Ljava/lang/Object;"), + ("java/util/function/DoublePredicate", "test(D)Z"), + ("java/util/function/DoubleSupplier", "getAsDouble()D"), + ("java/util/function/DoubleToIntFunction", "applyAsInt(D)I"), + ("java/util/function/DoubleToLongFunction", "applyAsLong(D)J"), + ("java/util/function/DoubleUnaryOperator", "applyAsDouble(D)D"), + ("java/util/function/Function", "apply(Ljava/lang/Object;)Ljava/lang/Object;"), + ("java/util/function/IntBinaryOperator", "applyAsInt(II)I"), + ("java/util/function/IntConsumer", "accept(I)V"), + ("java/util/function/IntFunction", "apply(I)Ljava/lang/Object;"), + ("java/util/function/IntPredicate", "test(I)Z"), + ("java/util/function/IntSupplier", "getAsInt()I"), + ("java/util/function/IntToDoubleFunction", "applyAsDouble(I)D"), + ("java/util/function/IntToLongFunction", "applyAsLong(I)J"), + ("java/util/function/IntUnaryOperator", "applyAsInt(I)I"), + ("java/util/function/LongBinaryOperator", "applyAsLong(JJ)J"), + ("java/util/function/LongConsumer", "accept(J)V"), + ("java/util/function/LongFunction", "apply(J)Ljava/lang/Object;"), + ("java/util/function/LongPredicate", "test(J)Z"), + ("java/util/function/LongSupplier", "getAsLong()J"), + ("java/util/function/LongToDoubleFunction", "applyAsDouble(J)D"), + ("java/util/function/LongToIntFunction", "applyAsInt(J)I"), + ("java/util/function/LongUnaryOperator", "applyAsLong(J)J"), + ("java/util/function/ObjDoubleConsumer", "accept(Ljava/lang/Object;D)V"), + ("java/util/function/ObjIntConsumer", "accept(Ljava/lang/Object;I)V"), + ("java/util/function/ObjLongConsumer", "accept(Ljava/lang/Object;J)V"), + ("java/util/function/Predicate", "test(Ljava/lang/Object;)Z"), + ("java/util/function/Supplier", "get()Ljava/lang/Object;"), + ("java/util/function/ToDoubleBiFunction", "applyAsDouble(Ljava/lang/Object;Ljava/lang/Object;)D"), + ("java/util/function/ToDoubleFunction", "applyAsDouble(Ljava/lang/Object;)D"), + ("java/util/function/ToIntBiFunction", "applyAsInt(Ljava/lang/Object;Ljava/lang/Object;)I"), + ("java/util/function/ToIntFunction", "applyAsInt(Ljava/lang/Object;)I"), + ("java/util/function/ToLongBiFunction", "applyAsLong(Ljava/lang/Object;Ljava/lang/Object;)J"), + ("java/util/function/ToLongFunction", "applyAsLong(Ljava/lang/Object;)J"), + ("java/util/function/UnaryOperator", "apply(Ljava/lang/Object;)Ljava/lang/Object;"), + ("com/sun/javafx/css/parser/Recognizer", "recognize(I)Z"), + ("java/awt/KeyEventDispatcher", "dispatchKeyEvent(Ljava/awt/event/KeyEvent;)Z"), + ("java/awt/KeyEventPostProcessor", "postProcessKeyEvent(Ljava/awt/event/KeyEvent;)Z"), + ("java/io/FileFilter", "accept(Ljava/io/File;)Z"), + ("java/io/FilenameFilter", "accept(Ljava/io/File;Ljava/lang/String;)Z"), + ("java/lang/Runnable", "run()V"), + ("java/lang/Thread$UncaughtExceptionHandler", "uncaughtException(Ljava/lang/Thread;Ljava/lang/Throwable;)V"), + ("java/nio/file/DirectoryStream$Filter", "accept(Ljava/lang/Object;)Z"), + ("java/nio/file/PathMatcher", "matches(Ljava/nio/file/Path;)Z"), + ("java/time/temporal/TemporalAdjuster", "adjustInto(Ljava/time/temporal/Temporal;)Ljava/time/temporal/Temporal;"), + ("java/time/temporal/TemporalQuery", "queryFrom(Ljava/time/temporal/TemporalAccessor;)Ljava/lang/Object;"), + ("java/util/Comparator", "compare(Ljava/lang/Object;Ljava/lang/Object;)I"), + ("java/util/concurrent/Callable", "call()Ljava/lang/Object;"), + ("java/util/logging/Filter", "isLoggable(Ljava/util/logging/LogRecord;)Z"), + ("java/util/prefs/PreferenceChangeListener", "preferenceChange(Ljava/util/prefs/PreferenceChangeEvent;)V"), + ("javafx/animation/Interpolatable", "interpolate(Ljava/lang/Object;D)Ljava/lang/Object;"), + ("javafx/beans/InvalidationListener", "invalidated(Ljavafx/beans/Observable;)V"), + ("javafx/beans/value/ChangeListener", "changed(Ljavafx/beans/value/ObservableValue;Ljava/lang/Object;Ljava/lang/Object;)V"), + ("javafx/collections/ListChangeListener", "onChanged(Ljavafx/collections/ListChangeListener$Change;)V"), + ("javafx/collections/MapChangeListener", "onChanged(Ljavafx/collections/MapChangeListener$Change;)V"), + ("javafx/collections/SetChangeListener", "onChanged(Ljavafx/collections/SetChangeListener$Change;)V"), + ("javafx/event/EventHandler", "handle(Ljavafx/event/Event;)V"), + ("javafx/util/Builder", "build()Ljava/lang/Object;"), + ("javafx/util/BuilderFactory", "getBuilder(Ljava/lang/Class;)Ljavafx/util/Builder;"), + ("javafx/util/Callback", "call(Ljava/lang/Object;)Ljava/lang/Object;") + ) + def javaSam(internalName: InternalName): Option[String] = javaSams.get(internalName) +} diff --git a/src/compiler/scala/tools/nsc/backend/jvm/opt/InstructionResultSize.scala b/src/compiler/scala/tools/nsc/backend/jvm/opt/InstructionResultSize.scala deleted file mode 100644 index 8d744f6d13..0000000000 --- a/src/compiler/scala/tools/nsc/backend/jvm/opt/InstructionResultSize.scala +++ /dev/null @@ -1,240 +0,0 @@ -package scala.tools.nsc.backend.jvm.opt - -import scala.annotation.switch -import scala.tools.asm.{Handle, Type, Opcodes} -import scala.tools.asm.tree._ - -object InstructionResultSize { - import Opcodes._ - def apply(instruction: AbstractInsnNode): Int = (instruction.getOpcode: @switch) match { - // The order of opcodes is (almost) the same as in Opcodes.java - case ACONST_NULL => 1 - - case ICONST_M1 | - ICONST_0 | - ICONST_1 | - ICONST_2 | - ICONST_3 | - ICONST_4 | - ICONST_5 => 1 - - case LCONST_0 | - LCONST_1 => 2 - - case FCONST_0 | - FCONST_1 | - FCONST_2 => 1 - - case DCONST_0 | - DCONST_1 => 2 - - case BIPUSH | - SIPUSH => 1 - - case LDC => - instruction.asInstanceOf[LdcInsnNode].cst match { - case _: java.lang.Integer | - _: java.lang.Float | - _: String | - _: Type | - _: Handle => 1 - - case _: java.lang.Long | - _: java.lang.Double => 2 - } - - case ILOAD | - FLOAD | - ALOAD => 1 - - case LLOAD | - DLOAD => 2 - - case IALOAD | - FALOAD | - AALOAD | - BALOAD | - CALOAD | - SALOAD => 1 - - case LALOAD | - DALOAD => 2 - - case ISTORE | - LSTORE | - FSTORE | - DSTORE | - ASTORE => 0 - - case IASTORE | - LASTORE | - FASTORE | - DASTORE | - AASTORE | - BASTORE | - CASTORE | - SASTORE => 0 - - case POP | - POP2 => 0 - - case DUP | - DUP_X1 | - DUP_X2 | - DUP2 | - DUP2_X1 | - DUP2_X2 | - SWAP => throw new IllegalArgumentException("Can't compute the size of DUP/SWAP without knowing what's on stack top") - - case IADD | - FADD => 1 - - case LADD | - DADD => 2 - - case ISUB | - FSUB => 1 - - case LSUB | - DSUB => 2 - - case IMUL | - FMUL => 1 - - case LMUL | - DMUL => 2 - - case IDIV | - FDIV => 1 - - case LDIV | - DDIV => 2 - - case IREM | - FREM => 1 - - case LREM | - DREM => 2 - - case INEG | - FNEG => 1 - - case LNEG | - DNEG => 2 - - case ISHL | - ISHR => 1 - - case LSHL | - LSHR => 2 - - case IUSHR => 1 - - case LUSHR => 2 - - case IAND | - IOR | - IXOR => 1 - - case LAND | - LOR | - LXOR => 2 - - case IINC => 1 - - case I2F | - L2I | - L2F | - F2I | - D2I | - D2F | - I2B | - I2C | - I2S => 1 - - case I2L | - I2D | - L2D | - F2L | - F2D | - D2L => 2 - - case LCMP | - FCMPL | - FCMPG | - DCMPL | - DCMPG => 1 - - case IFEQ | - IFNE | - IFLT | - IFGE | - IFGT | - IFLE => 0 - - case IF_ICMPEQ | - IF_ICMPNE | - IF_ICMPLT | - IF_ICMPGE | - IF_ICMPGT | - IF_ICMPLE | - IF_ACMPEQ | - IF_ACMPNE => 0 - - case GOTO => 0 - - case JSR => throw new IllegalArgumentException("Subroutines are not supported.") - - case RET => 0 - - case TABLESWITCH | - LOOKUPSWITCH => 0 - - case IRETURN | - FRETURN | - ARETURN => 1 - - case LRETURN | - DRETURN => 2 - - case RETURN => 0 - - case GETSTATIC => Type.getType(instruction.asInstanceOf[FieldInsnNode].desc).getSize - - case PUTSTATIC => 0 - - case GETFIELD => Type.getType(instruction.asInstanceOf[FieldInsnNode].desc).getSize - - case PUTFIELD => 0 - - case INVOKEVIRTUAL | - INVOKESPECIAL | - INVOKESTATIC | - INVOKEINTERFACE => - val desc = instruction.asInstanceOf[MethodInsnNode].desc - Type.getReturnType(desc).getSize - - case INVOKEDYNAMIC => - val desc = instruction.asInstanceOf[InvokeDynamicInsnNode].desc - Type.getReturnType(desc).getSize - - case NEW => 1 - - case NEWARRAY | - ANEWARRAY | - ARRAYLENGTH => 1 - - case ATHROW => 0 - - case CHECKCAST | - INSTANCEOF => 1 - - case MONITORENTER | - MONITOREXIT => 0 - - case MULTIANEWARRAY => 1 - - case IFNULL | - IFNONNULL => 0 - } -} diff --git a/src/compiler/scala/tools/nsc/backend/jvm/opt/LocalOpt.scala b/src/compiler/scala/tools/nsc/backend/jvm/opt/LocalOpt.scala index 4132710a96..9c22b09cdd 100644 --- a/src/compiler/scala/tools/nsc/backend/jvm/opt/LocalOpt.scala +++ b/src/compiler/scala/tools/nsc/backend/jvm/opt/LocalOpt.scala @@ -7,79 +7,180 @@ package scala.tools.nsc package backend.jvm package opt -import scala.annotation.switch -import scala.tools.asm.Opcodes -import scala.tools.asm.tree.analysis.{Analyzer, BasicInterpreter} +import scala.annotation.{tailrec, switch} + +import scala.tools.asm.Type +import scala.tools.asm.tree.analysis.Frame +import scala.tools.asm.Opcodes._ import scala.tools.asm.tree._ -import scala.collection.convert.decorateAsScala._ +import scala.collection.mutable +import scala.collection.JavaConverters._ import scala.tools.nsc.backend.jvm.BTypes.InternalName +import scala.tools.nsc.backend.jvm.analysis._ import scala.tools.nsc.backend.jvm.opt.BytecodeUtils._ /** - * Optimizations within a single method. + * Optimizations within a single method. Certain optimizations enable others, for example removing + * unreachable code can render a `try` block empty and enable removeEmptyExceptionHandlers. The + * latter in turn enables more unreachable code to be eliminated (the `catch` block), so there is + * a cyclic dependency. Optimizations that depend on each other are therefore executed in a loop + * until reaching a fixpoint. + * + * The optimizations marked UPSTREAM enable optimizations that were already executed, so they cause + * another iteration in the fixpoint loop. + * + * nullness optimizations: rewrite null-checking branches to GOTO if nullness is known + * + enables downstream + * - unreachable code (null / non-null branch becomes unreachable) + * - box-unbox elimination (may render an escaping consumer of a box unreachable) + * - stale stores (aload x is replaced by aconst_null if it's known null) + * - simplify jumps (replaces conditional jumps by goto, so may enable goto chains) + * + * unreachable code / DCE (removes instructions of basic blocks to which there is no branch) + * + enables downstream: + * - stale stores (loads may be eliminated, removing consumers of a store) + * - empty handlers (try blocks may become empty) + * - simplify jumps (goto l; [dead code]; l: ..) => remove goto + * - stale local variable descriptors + * - (not box-unbox, which is implemented using prod-cons, so it doesn't consider dead code) + * + * note that eliminating empty handlers and stale local variable descriptors is required for + * correctness, see the comment in the body of `methodOptimizations`. + * + * box-unbox elimination (eliminates box-unbox pairs within the same method) + * + enables UPSTREAM: + * - nullness optimizations (a box extraction operation (unknown nullness) may be rewritten to + * a read of a non-null local. example in doc comment of box-unbox implementation) + * - further box-unbox elimination (e.g. an Integer stored in a Tuple; eliminating the tuple may + * enable eliminating the Integer) + * + enables downstream: + * - copy propagation (new locals are introduced, may be aliases of existing) + * - stale stores (multi-value boxes where not all values are used) + * - redundant casts (`("a", "b")._1`: the generic `_1` method returns `Object`, a cast + * to String is added. The cast is redundant after eliminating the tuple.) + * - empty local variable descriptors (local variables that were holding the box may become unused) + * + * copy propagation (replaces LOAD n to the LOAD m for the smallest m that is an alias of n) + * + enables downstream: + * - stale stores (a stored value may not be loaded anymore) + * - store-load pairs (a load n may now be right after a store n) + * + NOTE: copy propagation is only executed once, in the first fixpoint loop iteration. none of + * the other optimizations enables further copy prop. we still run it as part of the loop + * because it requires unreachable code to be eliminated. + * + * stale stores (replace STORE by POP) + * + enables downstream: + * - push-pop (the new pop may be the single consumer for an instruction) + * + * redundant casts: eliminates casts that are statically known to succeed (uses type propagation) + * + enables UPSTREAM: + * - box-unbox elimination (a removed checkcast may be a box consumer) + * + enables downstream: + * - push-pop for closure allocation elimination (every indyLambda is followed by a checkcast, see SI-9540) + * + * push-pop (when a POP is the only consumer of a value, remove the POP and its producer) + * + enables UPSTREAM: + * - stale stores (if a LOAD is removed, a corresponding STORE may become stale) + * - box-unbox elimination (push-pop may eliminate a closure allocation, rendering a captured + * box non-escaping) + * + enables downstream: + * - store-load pairs (a variable may become non-live) + * - stale handlers (push-pop removes code) + * - simplify jumps (push-pop removes code) + * + * store-load pairs (remove `STORE x; LOAD x` if x is otherwise not used in the method) + * + enables downstream: + * - empty handlers (code is removes, a try block may become empty + * - simplify jumps (code is removed, a goto may become redundant for example) + * - stale local variable descriptors * - * unreachable code - * - removes instructions of basic blocks to which no branch instruction points - * + enables eliminating some exception handlers and local variable descriptors - * > eliminating them is required for correctness, as explained in `removeUnreachableCode` + * empty handlers (removes exception handlers whose try block is empty) + * + enables UPSTREAM: + * - unreachable code (catch block becomes unreachable) + * - box-unbox (a box may be escape in an operation in a dead handler) + * + enables downstream: + * - simplify jumps * - * empty exception handlers - * - removes exception handlers whose try block is empty - * + eliminating a handler where the try block is empty and reachable will turn the catch block - * unreachable. in this case "unreachable code" is invoked recursively until reaching a fixpoint. - * > for try blocks that are unreachable, "unreachable code" removes also the instructions of the - * catch block, and the recursive invocation is not necessary. + * simplify jumps (various, like `GOTO l; l: ...`, see doc comments of individual optimizations) + * + enables UPSTREAM + * - unreachable code (`GOTO a; a: GOTO b; b: ...`, the first jump is changed to `GOTO b`, the second becomes unreachable) + * - store-load pairs (a `GOTO l; l: ...` is removed between store and load) + * - push-pop (`IFNULL l; l: ...` is replaced by `POP`) * - * simplify jumps - * - various simplifications, see doc comments of individual optimizations - * + changing or eliminating jumps may render some code unreachable, therefore "simplify jumps" is - * executed in a loop with "unreachable code" * - * empty local variable descriptors - * - removes entries from the local variable table where the variable is not actually used - * + enables eliminating labels that the entry points to (if they are not otherwise referenced) + * The following cleanup optimizations don't enable any upstream optimizations, so they can be + * executed once at the end, when the above optimizations reach a fixpoint. * - * empty line numbers - * - eliminates line number nodes that describe no executable instructions - * + enables eliminating the label of the line number node (if it's not otherwise referenced) * - * stale labels - * - eliminate labels that are not referenced, merge sequences of label definitions. + * empty local variable descriptors (removes unused variables from the local variable table) + * + enables downstream: + * - stale labels (labels that the entry points to, if not otherwise referenced) + * + * empty line numbers (eliminates line number nodes that describe no executable instructions) + * + enables downstream: + * - stale labels (label of the line number node, if not otherwise referenced) + * + * stale labels (eliminate labels that are not referenced, merge sequences of label definitions) + * + * + * Note on a method's maxLocals / maxStack: the backend only uses those values for running + * Analyzers. The values can be conservative approximations: if an optimization removes code and + * the maximal stack size is now smaller, the larger maxStack value will still work fine for + * running an Analyzer (just that frames allocate more space than required). The correct max + * values written to the bytecode are re-computed during classfile serialization. + * To keep things simpler, we don't update the max values in every optimization: + * - we do it in `removeUnreachableCodeImpl`, because it's quite straightforward + * - maxLocals is updated in `compactLocalVariables`, which runs at the end of method optimizations + * + * + * Note on updating the call graph: whenever an optimization eliminates a callsite or a closure + * instantiation, we eliminate the corresponding entry from the call graph. */ class LocalOpt[BT <: BTypes](val btypes: BT) { import LocalOptImpls._ import btypes._ + import coreBTypes._ + import backendUtils._ + + val boxUnbox = new BoxUnbox(btypes) + import boxUnbox._ + + val copyProp = new CopyProp(btypes) + import copyProp._ /** * Remove unreachable code from a method. * * This implementation only removes instructions that are unreachable for an ASM analyzer / * interpreter. This ensures that future analyses will not produce `null` frames. The inliner - * and call graph builder depend on this property. + * depends on this property. * * @return A set containing the eliminated instructions */ - def minimalRemoveUnreachableCode(method: MethodNode, ownerClassName: InternalName): Set[AbstractInsnNode] = { - if (method.instructions.size == 0) return Set.empty // fast path for abstract methods - if (unreachableCodeEliminated(method)) return Set.empty // we know there is no unreachable code + def minimalRemoveUnreachableCode(method: MethodNode, ownerClassName: InternalName): Boolean = { + // In principle, for the inliner, a single removeUnreachableCodeImpl would be enough. But that + // would potentially leave behind stale handlers (empty try block) which is not legal in the + // classfile. So we run both removeUnreachableCodeImpl and removeEmptyExceptionHandlers. + if (method.instructions.size == 0) return false // fast path for abstract methods + if (unreachableCodeEliminated(method)) return false // we know there is no unreachable code + if (!AsmAnalyzer.sizeOKForBasicValue(method)) return false // the method is too large for running an analyzer // For correctness, after removing unreachable code, we have to eliminate empty exception // handlers, see scaladoc of def methodOptimizations. Removing an live handler may render more // code unreachable and therefore requires running another round. - def removalRound(): Set[AbstractInsnNode] = { - val (removedInstructions, liveLabels) = removeUnreachableCodeImpl(method, ownerClassName) - val removedRecursively = if (removedInstructions.nonEmpty) { + def removalRound(): Boolean = { + val (insnsRemoved, liveLabels) = removeUnreachableCodeImpl(method, ownerClassName) + if (insnsRemoved) { val liveHandlerRemoved = removeEmptyExceptionHandlers(method).exists(h => liveLabels(h.start)) if (liveHandlerRemoved) removalRound() - else Set.empty - } else Set.empty - removedInstructions ++ removedRecursively + } + insnsRemoved } - val removedInstructions = removalRound() - if (removedInstructions.nonEmpty) removeUnusedLocalVariableNodes(method)() + val changed = removalRound() + if (changed) removeUnusedLocalVariableNodes(method)() unreachableCodeEliminated += method - removedInstructions + changed } /** @@ -90,21 +191,13 @@ class LocalOpt[BT <: BTypes](val btypes: BT) { * @return `true` if unreachable code was eliminated in some method, `false` otherwise. */ def methodOptimizations(clazz: ClassNode): Boolean = { - !compilerSettings.YoptNone && clazz.methods.asScala.foldLeft(false) { + !compilerSettings.optNone && clazz.methods.asScala.foldLeft(false) { case (changed, method) => methodOptimizations(method, clazz.name) || changed } } /** - * Remove unreachable code from a method. - * - * We rely on dead code elimination provided by the ASM framework, as described in the ASM User - * Guide (http://asm.ow2.org/index.html), Section 8.2.1. It runs a data flow analysis, which only - * computes Frame information for reachable instructions. Instructions for which no Frame data is - * available after the analysis are unreachable. - * - * Also simplifies branching instructions, removes unused local variable descriptors, empty - * exception handlers, unnecessary label declarations and empty line number nodes. + * Run method-level optimizations, see comment on class [[LocalOpt]]. * * Returns `true` if the bytecode of `method` was changed. */ @@ -137,36 +230,151 @@ class LocalOpt[BT <: BTypes](val btypes: BT) { // This triggers "ClassFormatError: Illegal exception table range in class file C". Similar // for local variables in dead blocks. Maybe that's a bug in the ASM framework. - def removalRound(): Boolean = { - // unreachable-code, empty-handlers and simplify-jumps run until reaching a fixpoint (see doc on class LocalOpt) - val (codeRemoved, handlersRemoved, liveHandlerRemoved) = if (compilerSettings.YoptUnreachableCode) { - val (removedInstructions, liveLabels) = removeUnreachableCodeImpl(method, ownerClassName) - val removedHandlers = removeEmptyExceptionHandlers(method) - (removedInstructions.nonEmpty, removedHandlers.nonEmpty, removedHandlers.exists(h => liveLabels(h.start))) - } else { - (false, false, false) + var currentTrace: String = null + val methodPrefix = {val p = compilerSettings.YoptTrace.value; if (p == "_") "" else p } + val doTrace = compilerSettings.YoptTrace.isSetByUser && s"$ownerClassName.${method.name}".startsWith(methodPrefix) + def traceIfChanged(optName: String): Unit = if (doTrace) { + val after = AsmUtils.textify(method) + if (currentTrace != after) { + println(s"after $optName") + println(after) } - - val jumpsChanged = if (compilerSettings.YoptSimplifyJumps) simplifyJumps(method) else false - - // Eliminating live handlers and simplifying jump instructions may render more code - // unreachable, so we need to run another round. - if (liveHandlerRemoved || jumpsChanged) removalRound() - - codeRemoved || handlersRemoved || jumpsChanged + currentTrace = after } - val codeHandlersOrJumpsChanged = removalRound() + /** + * Runs the optimizations that depend on each other in a loop until reaching a fixpoint. See + * comment in class [[LocalOpt]]. + * + * Returns a pair of booleans (codeChanged, requireEliminateUnusedLocals). + */ + def removalRound( + requestNullness: Boolean, + requestDCE: Boolean, + requestBoxUnbox: Boolean, + requestStaleStores: Boolean, + requestPushPop: Boolean, + requestStoreLoad: Boolean, + firstIteration: Boolean, + maxRecursion: Int = 10): (Boolean, Boolean) = { + if (maxRecursion == 0) return (false, false) + + traceIfChanged("beforeMethodOpt") + + // NULLNESS OPTIMIZATIONS + val runNullness = compilerSettings.optNullnessTracking && requestNullness + val nullnessOptChanged = runNullness && nullnessOptimizations(method, ownerClassName) + traceIfChanged("nullness") + + // UNREACHABLE CODE + // Both AliasingAnalyzer (used in copyProp) and ProdConsAnalyzer (used in eliminateStaleStores, + // boxUnboxElimination) require not having unreachable instructions (null frames). + val runDCE = (compilerSettings.optUnreachableCode && (requestDCE || nullnessOptChanged)) || + compilerSettings.optBoxUnbox || + compilerSettings.optCopyPropagation + val (codeRemoved, liveLabels) = if (runDCE) removeUnreachableCodeImpl(method, ownerClassName) else (false, Set.empty[LabelNode]) + traceIfChanged("dce") + + // BOX-UNBOX + val runBoxUnbox = compilerSettings.optBoxUnbox && (requestBoxUnbox || nullnessOptChanged) + val boxUnboxChanged = runBoxUnbox && boxUnboxElimination(method, ownerClassName) + traceIfChanged("boxUnbox") + + // COPY PROPAGATION + val runCopyProp = compilerSettings.optCopyPropagation && (firstIteration || boxUnboxChanged) + val copyPropChanged = runCopyProp && copyPropagation(method, ownerClassName) + traceIfChanged("copyProp") + + // STALE STORES + val runStaleStores = compilerSettings.optCopyPropagation && (requestStaleStores || nullnessOptChanged || codeRemoved || boxUnboxChanged || copyPropChanged) + val storesRemoved = runStaleStores && eliminateStaleStores(method, ownerClassName) + traceIfChanged("staleStores") + + // REDUNDANT CASTS + val runRedundantCasts = compilerSettings.optRedundantCasts && (firstIteration || boxUnboxChanged) + val castRemoved = runRedundantCasts && eliminateRedundantCasts(method, ownerClassName) + traceIfChanged("redundantCasts") + + // PUSH-POP + val runPushPop = compilerSettings.optCopyPropagation && (requestPushPop || firstIteration || storesRemoved || castRemoved) + val pushPopRemoved = runPushPop && eliminatePushPop(method, ownerClassName) + traceIfChanged("pushPop") + + // STORE-LOAD PAIRS + val runStoreLoad = compilerSettings.optCopyPropagation && (requestStoreLoad || boxUnboxChanged || copyPropChanged || pushPopRemoved) + val storeLoadRemoved = runStoreLoad && eliminateStoreLoad(method) + traceIfChanged("storeLoadPairs") + + // STALE HANDLERS + val removedHandlers = if (runDCE) removeEmptyExceptionHandlers(method) else Set.empty[TryCatchBlockNode] + val handlersRemoved = removedHandlers.nonEmpty + val liveHandlerRemoved = removedHandlers.exists(h => liveLabels(h.start)) + traceIfChanged("staleHandlers") + + // SIMPLIFY JUMPS + // almost all of the above optimizations enable simplifying more jumps, so we just run it in every iteration + val runSimplifyJumps = compilerSettings.optSimplifyJumps + val jumpsChanged = runSimplifyJumps && simplifyJumps(method) + traceIfChanged("simplifyJumps") + + // See doc comment in the beginning of this file (optimizations marked UPSTREAM) + val runNullnessAgain = boxUnboxChanged + val runDCEAgain = liveHandlerRemoved || jumpsChanged + val runBoxUnboxAgain = boxUnboxChanged || castRemoved || pushPopRemoved || liveHandlerRemoved + val runStaleStoresAgain = pushPopRemoved + val runPushPopAgain = jumpsChanged + val runStoreLoadAgain = jumpsChanged + val runAgain = runNullnessAgain || runDCEAgain || runBoxUnboxAgain || pushPopRemoved || runStaleStoresAgain || runPushPopAgain || runStoreLoadAgain + + val downstreamRequireEliminateUnusedLocals = runAgain && removalRound( + requestNullness = runNullnessAgain, + requestDCE = runDCEAgain, + requestBoxUnbox = runBoxUnboxAgain, + requestStaleStores = runStaleStoresAgain, + requestPushPop = runPushPopAgain, + requestStoreLoad = runStoreLoadAgain, + firstIteration = false, + maxRecursion = maxRecursion - 1)._2 + + val requireEliminateUnusedLocals = downstreamRequireEliminateUnusedLocals || + nullnessOptChanged || // nullness opt may eliminate stores / loads, rendering a local unused + codeRemoved || // see comment in method `methodOptimizations` + boxUnboxChanged || // box-unbox renders locals (holding boxes) unused + storesRemoved || + storeLoadRemoved || + handlersRemoved + + val codeChanged = nullnessOptChanged || codeRemoved || boxUnboxChanged || castRemoved || copyPropChanged || storesRemoved || pushPopRemoved || storeLoadRemoved || handlersRemoved || jumpsChanged + (codeChanged, requireEliminateUnusedLocals) + } - // (*) Removing stale local variable descriptors is required for correctness of unreachable-code + val (nullnessDceBoxesCastsCopypropPushpopOrJumpsChanged, requireEliminateUnusedLocals) = if (AsmAnalyzer.sizeOKForBasicValue(method)) { + // we run DCE even if the method is already in the `unreachableCodeEliminated` map: the DCE + // here is more thorough than `minimalRemoveUnreachableCode` that run before inlining. + val r = removalRound( + requestNullness = true, + requestDCE = true, + requestBoxUnbox = true, + requestStaleStores = true, + requestPushPop = true, + requestStoreLoad = true, + firstIteration = true) + if (compilerSettings.optUnreachableCode) unreachableCodeEliminated += method + r + } else (false, false) + + // (*) Removing stale local variable descriptors is required for correctness, see comment in `methodOptimizations` val localsRemoved = - if (compilerSettings.YoptCompactLocals) compactLocalVariables(method) // also removes unused - else if (compilerSettings.YoptUnreachableCode) removeUnusedLocalVariableNodes(method)() // (*) + if (compilerSettings.optCompactLocals) compactLocalVariables(method) // also removes unused + else if (requireEliminateUnusedLocals) removeUnusedLocalVariableNodes(method)() // (*) else false + traceIfChanged("localVariables") - val lineNumbersRemoved = if (compilerSettings.YoptEmptyLineNumbers) removeEmptyLineNumbers(method) else false + val lineNumbersRemoved = if (compilerSettings.optUnreachableCode) removeEmptyLineNumbers(method) else false + traceIfChanged("lineNumbers") - val labelsRemoved = if (compilerSettings.YoptEmptyLabels) removeEmptyLabelNodes(method) else false + val labelsRemoved = if (compilerSettings.optUnreachableCode) removeEmptyLabelNodes(method) else false + traceIfChanged("labels") // assert that local variable annotations are empty (we don't emit them) - otherwise we'd have // to eliminate those covering an empty range, similar to removeUnusedLocalVariableNodes. @@ -174,53 +382,198 @@ class LocalOpt[BT <: BTypes](val btypes: BT) { assert(nullOrEmpty(method.visibleLocalVariableAnnotations), method.visibleLocalVariableAnnotations) assert(nullOrEmpty(method.invisibleLocalVariableAnnotations), method.invisibleLocalVariableAnnotations) - unreachableCodeEliminated += method - - codeHandlersOrJumpsChanged || localsRemoved || lineNumbersRemoved || labelsRemoved + nullnessDceBoxesCastsCopypropPushpopOrJumpsChanged || localsRemoved || lineNumbersRemoved || labelsRemoved } -} + /** + * Apply various optimizations based on nullness analysis information. + * - IFNULL / IFNONNULL are rewritten to GOTO if nullness is known + * - IF_ACMPEQ / IF_ACMPNE are rewritten to GOTO if the both references are known null, or if + * one is known null and the other known not-null + * - ALOAD is replaced by ACONST_NULL if the local is known to hold null + * - ASTORE of null is removed if the local is known to hold null + * - INSTANCEOF of null is replaced by `ICONST_0` + * - scala.runtime.BoxesRunTime.unboxToX(null) is rewritten to a zero-value load + */ + def nullnessOptimizations(method: MethodNode, ownerClassName: InternalName): Boolean = { + AsmAnalyzer.sizeOKForNullness(method) && { + lazy val nullnessAnalyzer = new AsmAnalyzer(method, ownerClassName, new NullnessAnalyzer(btypes, method)) + + // When running nullness optimizations the method may still have unreachable code. Analyzer + // frames of unreachable instructions are `null`. + def frameAt(insn: AbstractInsnNode): Option[Frame[NullnessValue]] = Option(nullnessAnalyzer.frameAt(insn)) + + def nullness(insn: AbstractInsnNode, slot: Int): Option[NullnessValue] = { + frameAt(insn).map(_.getValue(slot)) + } + + def isNull(insn: AbstractInsnNode, slot: Int) = nullness(insn, slot).contains(NullValue) + + // cannot change instructions while iterating, it gets the analysis out of synch (indexed by instructions) + val toReplace = mutable.Map.empty[AbstractInsnNode, List[AbstractInsnNode]] + + val it = method.instructions.iterator() + while (it.hasNext) it.next() match { + case vi: VarInsnNode if isNull(vi, vi.`var`) => + if (vi.getOpcode == ALOAD) + toReplace(vi) = List(new InsnNode(ACONST_NULL)) + else if (vi.getOpcode == ASTORE) + for (frame <- frameAt(vi) if frame.peekStack(0) == NullValue) + toReplace(vi) = List(getPop(1)) + + case ji: JumpInsnNode => + val isIfNull = ji.getOpcode == IFNULL + val isIfNonNull = ji.getOpcode == IFNONNULL + if (isIfNull || isIfNonNull) for (frame <- frameAt(ji)) { + val nullness = frame.peekStack(0) + val taken = nullness == NullValue && isIfNull || nullness == NotNullValue && isIfNonNull + val avoided = nullness == NotNullValue && isIfNull || nullness == NullValue && isIfNonNull + if (taken || avoided) { + val jump = if (taken) List(new JumpInsnNode(GOTO, ji.label)) else Nil + toReplace(ji) = getPop(1) :: jump + } + } else { + val isIfEq = ji.getOpcode == IF_ACMPEQ + val isIfNe = ji.getOpcode == IF_ACMPNE + if (isIfEq || isIfNe) for (frame <- frameAt(ji)) { + val aNullness = frame.peekStack(1) + val bNullness = frame.peekStack(0) + val eq = aNullness == NullValue && bNullness == NullValue + val ne = aNullness == NullValue && bNullness == NotNullValue || aNullness == NotNullValue && bNullness == NullValue + val taken = isIfEq && eq || isIfNe && ne + val avoided = isIfEq && ne || isIfNe && eq + if (taken || avoided) { + val jump = if (taken) List(new JumpInsnNode(GOTO, ji.label)) else Nil + toReplace(ji) = getPop(1) :: getPop(1) :: jump + } + } + } + + case ti: TypeInsnNode => + if (ti.getOpcode == INSTANCEOF) for (frame <- frameAt(ti) if frame.peekStack(0) == NullValue) { + toReplace(ti) = List(getPop(1), new InsnNode(ICONST_0)) + } + + case mi: MethodInsnNode => + if (isScalaUnbox(mi)) for (frame <- frameAt(mi) if frame.peekStack(0) == NullValue) { + toReplace(mi) = List( + getPop(1), + loadZeroForTypeSort(Type.getReturnType(mi.desc).getSort)) + } + + case _ => + } + + def removeFromCallGraph(insn: AbstractInsnNode): Unit = insn match { + case mi: MethodInsnNode => callGraph.removeCallsite(mi, method) + case _ => + } + + for ((oldOp, newOps) <- toReplace) { + for (newOp <- newOps) method.instructions.insertBefore(oldOp, newOp) + method.instructions.remove(oldOp) + removeFromCallGraph(oldOp) + } + + toReplace.nonEmpty + } + } -object LocalOptImpls { /** * Removes unreachable basic blocks. * - * TODO: rewrite, don't use computeMaxLocalsMaxStack (runs a ClassWriter) / Analyzer. Too slow. - * * @return A set containing eliminated instructions, and a set containing all live label nodes. */ - def removeUnreachableCodeImpl(method: MethodNode, ownerClassName: InternalName): (Set[AbstractInsnNode], Set[LabelNode]) = { - // The data flow analysis requires the maxLocals / maxStack fields of the method to be computed. - computeMaxLocalsMaxStack(method) - val a = new Analyzer(new BasicInterpreter) - a.analyze(ownerClassName, method) - val frames = a.getFrames + def removeUnreachableCodeImpl(method: MethodNode, ownerClassName: InternalName): (Boolean, Set[LabelNode]) = { + val a = new AsmAnalyzer(method, ownerClassName) + val frames = a.analyzer.getFrames - val initialSize = method.instructions.size var i = 0 var liveLabels = Set.empty[LabelNode] - var removedInstructions = Set.empty[AbstractInsnNode] + var changed = false + var maxLocals = parametersSize(method) + var maxStack = 0 val itr = method.instructions.iterator() while (itr.hasNext) { - itr.next() match { - case l: LabelNode => - if (frames(i) != null) liveLabels += l + val insn = itr.next() + val isLive = frames(i) != null + if (isLive) maxStack = math.max(maxStack, frames(i).getStackSize) - case ins => + insn match { + case l: LabelNode => // label nodes are not removed: they might be referenced for example in a LocalVariableNode - if (frames(i) == null || ins.getOpcode == Opcodes.NOP) { + if (isLive) liveLabels += l + + case v: VarInsnNode if isLive => + val longSize = if (isSize2LoadOrStore(v.getOpcode)) 1 else 0 + maxLocals = math.max(maxLocals, v.`var` + longSize + 1) // + 1 because local numbers are 0-based + + case i: IincInsnNode if isLive => + maxLocals = math.max(maxLocals, i.`var` + 1) + + case _ => + if (!isLive || insn.getOpcode == NOP) { // Instruction iterators allow removing during iteration. // Removing is O(1): instructions are doubly linked list elements. itr.remove() - removedInstructions += ins + changed = true + insn match { + case invocation: MethodInsnNode => callGraph.removeCallsite(invocation, method) + case indy: InvokeDynamicInsnNode => callGraph.removeClosureInstantiation(indy, method) + case _ => + } } } i += 1 } - (removedInstructions, liveLabels) + method.maxLocals = maxLocals + method.maxStack = maxStack + (changed, liveLabels) } /** + * Eliminate `CHECKCAST` instructions that are statically known to succeed. This is safe if the + * tested object is null: `null.asInstanceOf` always succeeds. + * + * The type of the tested object is determined using a NonLubbingTypeFlowAnalyzer. Note that this + * analysis collapses LUBs of non-equal references types to Object for simplicity. Example: + * given `B <: A <: Object`, the cast in `(if (..) new B else new A).asInstanceOf[A]` would not + * be eliminated. + * + * Note: we cannot replace `INSTANCEOF` tests by only looking at the types, `null.isInstanceOf` + * always returns false, so we'd also need nullness information. + */ + def eliminateRedundantCasts(method: MethodNode, owner: InternalName): Boolean = { + AsmAnalyzer.sizeOKForBasicValue(method) && { + def isSubType(aRefDesc: String, bClass: InternalName): Boolean = aRefDesc == bClass || bClass == ObjectRef.internalName || { + (bTypeForDescriptorOrInternalNameFromClassfile(aRefDesc) conformsTo classBTypeFromParsedClassfile(bClass)).getOrElse(false) + } + + lazy val typeAnalyzer = new NonLubbingTypeFlowAnalyzer(method, owner) + + // cannot remove instructions while iterating, it gets the analysis out of synch (indexed by instructions) + val toRemove = mutable.Set.empty[TypeInsnNode] + + val it = method.instructions.iterator() + while (it.hasNext) it.next() match { + case ti: TypeInsnNode if ti.getOpcode == CHECKCAST => + val frame = typeAnalyzer.frameAt(ti) + val valueTp = frame.getValue(frame.stackTop) + if (valueTp.isReference && isSubType(valueTp.getType.getDescriptor, ti.desc)) { + toRemove += ti + } + + case _ => + } + + toRemove foreach method.instructions.remove + toRemove.nonEmpty + } + } +} + +object LocalOptImpls { + /** * Remove exception handlers that cover empty code blocks. A block is considered empty if it * consist only of labels, frames, line numbers, nops and gotos. * @@ -235,16 +588,16 @@ object LocalOptImpls { def removeEmptyExceptionHandlers(method: MethodNode): Set[TryCatchBlockNode] = { /** True if there exists code between start and end. */ def containsExecutableCode(start: AbstractInsnNode, end: LabelNode): Boolean = { - start != end && ((start.getOpcode : @switch) match { + start != end && ((start.getOpcode: @switch) match { // FrameNode, LabelNode and LineNumberNode have opcode == -1. - case -1 | Opcodes.GOTO => containsExecutableCode(start.getNext, end) + case -1 | GOTO => containsExecutableCode(start.getNext, end) case _ => true }) } var removedHandlers = Set.empty[TryCatchBlockNode] val handlersIter = method.tryCatchBlocks.iterator() - while(handlersIter.hasNext) { + while (handlersIter.hasNext) { val handler = handlersIter.next() if (!containsExecutableCode(handler.start, handler.end)) { removedHandlers += handler @@ -263,9 +616,10 @@ object LocalOptImpls { * same type or name. */ def removeUnusedLocalVariableNodes(method: MethodNode)(firstLocalIndex: Int = parametersSize(method), renumber: Int => Int = identity): Boolean = { - def variableIsUsed(start: AbstractInsnNode, end: LabelNode, varIndex: Int): Boolean = { + @tailrec def variableIsUsed(start: AbstractInsnNode, end: LabelNode, varIndex: Int): Boolean = { start != end && (start match { case v: VarInsnNode if v.`var` == varIndex => true + case i: IincInsnNode if i.`var` == varIndex => true case _ => variableIsUsed(start.getNext, end, varIndex) }) } @@ -285,17 +639,6 @@ object LocalOptImpls { } /** - * The number of local variable slots used for parameters and for the `this` reference. - */ - private def parametersSize(method: MethodNode): Int = { - // Double / long fields occupy two slots, so we sum up the sizes. Since getSize returns 0 for - // void, we have to add `max 1`. - val paramsSize = scala.tools.asm.Type.getArgumentTypes(method.desc).iterator.map(_.getSize max 1).sum - val thisSize = if ((method.access & Opcodes.ACC_STATIC) == 0) 1 else 0 - paramsSize + thisSize - } - - /** * Compact the local variable slots used in the method's implementation. This prevents having * unused slots for example after eliminating unreachable code. * @@ -310,12 +653,9 @@ object LocalOptImpls { val renumber = collection.mutable.ArrayBuffer.empty[Int] // Add the index of the local variable used by `varIns` to the `renumber` array. - def addVar(varIns: VarInsnNode): Unit = { - val index = varIns.`var` - val isWide = (varIns.getOpcode: @switch) match { - case Opcodes.LLOAD | Opcodes.DLOAD | Opcodes.LSTORE | Opcodes.DSTORE => true - case _ => false - } + def addVar(varIns: AbstractInsnNode, slot: Int): Unit = { + val index = slot + val isWide = isSize2LoadOrStore(varIns.getOpcode) // Ensure the length of `renumber`. Unused variable indices are mapped to -1. val minLength = if (isWide) index + 2 else index + 1 @@ -332,7 +672,7 @@ object LocalOptImpls { val firstLocalIndex = parametersSize(method) for (i <- 0 until firstLocalIndex) renumber += i // parameters and `this` are always used. method.instructions.iterator().asScala foreach { - case VarInstruction(varIns) => addVar(varIns) + case VarInstruction(varIns, slot) => addVar(varIns, slot) case _ => } @@ -353,10 +693,12 @@ object LocalOptImpls { // update variable instructions according to the renumber table method.maxLocals = nextIndex method.instructions.iterator().asScala.foreach { - case VarInstruction(varIns) => - val oldIndex = varIns.`var` - if (oldIndex >= firstLocalIndex && renumber(oldIndex) != oldIndex) - varIns.`var` = renumber(varIns.`var`) + case VarInstruction(varIns, slot) => + val oldIndex = slot + if (oldIndex >= firstLocalIndex && renumber(oldIndex) != oldIndex) varIns match { + case vi: VarInsnNode => vi.`var` = renumber(slot) + case ii: IincInsnNode => ii.`var` = renumber(slot) + } case _ => } true @@ -431,154 +773,181 @@ object LocalOptImpls { // A set of all exception handlers that guard the current instruction, required for simplifyGotoReturn var activeHandlers = Set.empty[TryCatchBlockNode] - // Instructions that need to be removed. simplifyBranchOverGoto returns an instruction to be - // removed. It cannot remove it itself because the instruction may be the successor of the current - // instruction of the iterator, which is not supported in ASM. - var instructionsToRemove = Set.empty[AbstractInsnNode] + val jumpInsns = mutable.LinkedHashMap.empty[JumpInsnNode, Boolean] - val iterator = method.instructions.iterator() - while (iterator.hasNext) { - val instruction = iterator.next() + for (insn <- method.instructions.iterator().asScala) insn match { + case l: LabelNode => + activeHandlers ++= allHandlers.filter(_.start == l) + activeHandlers = activeHandlers.filter(_.end != l) - instruction match { - case l: LabelNode => - activeHandlers ++= allHandlers.filter(_.start == l) - activeHandlers = activeHandlers.filter(_.end != l) - case _ => + case ji: JumpInsnNode => + jumpInsns(ji) = activeHandlers.nonEmpty + + case _ => + } + + var _jumpTargets: Set[AbstractInsnNode] = null + def jumpTargets = { + if (_jumpTargets == null) { + _jumpTargets = jumpInsns.keysIterator.map(_.label).toSet } + _jumpTargets + } - if (instructionsToRemove(instruction)) { - iterator.remove() - instructionsToRemove -= instruction - } else if (isJumpNonJsr(instruction)) { // fast path - all of the below only treat jumps - var jumpRemoved = simplifyThenElseSameTarget(method, instruction) + def removeJumpFromMap(jump: JumpInsnNode) = { + jumpInsns.remove(jump) + _jumpTargets = null + } - if (!jumpRemoved) { - changed = collapseJumpChains(instruction) || changed - jumpRemoved = removeJumpToSuccessor(method, instruction) + def replaceJumpByPop(jump: JumpInsnNode) = { + removeJumpAndAdjustStack(method, jump) + removeJumpFromMap(jump) + } - if (!jumpRemoved) { - val staleGoto = simplifyBranchOverGoto(method, instruction) - instructionsToRemove ++= staleGoto - changed ||= staleGoto.nonEmpty - changed = simplifyGotoReturn(method, instruction, inTryBlock = activeHandlers.nonEmpty) || changed - } + /** + * Removes a conditional jump if it is followed by a GOTO to the same destination. + * + * CondJump l; [nops]; GOTO l; [...] + * POP*; [nops]; GOTO l; [...] + * + * Introduces 1 or 2 POP instructions, depending on the number of values consumed by the CondJump. + */ + def simplifyThenElseSameTarget(insn: AbstractInsnNode): Boolean = insn match { + case ConditionalJump(jump) => + nextExecutableInstruction(insn) match { + case Some(Goto(elseJump)) if sameTargetExecutableInstruction(jump, elseJump) => + replaceJumpByPop(jump) + true + + case _ => false } - changed ||= jumpRemoved - } + + case _ => false } - assert(instructionsToRemove.isEmpty, "some optimization required removing a previously traversed instruction. add `instructionsToRemove.foreach(method.instructions.remove)`") - changed - } - /** - * Removes a conditional jump if it is followed by a GOTO to the same destination. - * - * CondJump l; [nops]; GOTO l; [...] - * POP*; [nops]; GOTO l; [...] - * - * Introduces 1 or 2 POP instructions, depending on the number of values consumed by the CondJump. - */ - private def simplifyThenElseSameTarget(method: MethodNode, instruction: AbstractInsnNode): Boolean = instruction match { - case ConditionalJump(jump) => - nextExecutableInstruction(instruction) match { - case Some(Goto(elseJump)) if sameTargetExecutableInstruction(jump, elseJump) => - removeJumpAndAdjustStack(method, jump) + /** + * Replace jumps to a sequence of GOTO instructions by a jump to the final destination. + * + * {{{ + * Jump l; [any ops]; l: GOTO m; [any ops]; m: GOTO n; [any ops]; n: NotGOTO; [...] + * => Jump n; [rest unchanged] + * }}} + * + * If there's a loop of GOTOs, the initial jump is replaced by one of the labels in the loop. + */ + def collapseJumpChains(insn: AbstractInsnNode): Boolean = insn match { + case JumpNonJsr(jump) => + val target = finalJumpTarget(jump) + if (jump.label == target) false else { + jump.label = target + _jumpTargets = null true + } - case _ => false - } - case _ => false - } + case _ => false + } - /** - * Replace jumps to a sequence of GOTO instructions by a jump to the final destination. - * - * Jump l; [any ops]; l: GOTO m; [any ops]; m: GOTO n; [any ops]; n: NotGOTO; [...] - * => Jump n; [rest unchanged] - * - * If there's a loop of GOTOs, the initial jump is replaced by one of the labels in the loop. - */ - private def collapseJumpChains(instruction: AbstractInsnNode): Boolean = instruction match { - case JumpNonJsr(jump) => - val target = finalJumpTarget(jump) - if (jump.label == target) false else { - jump.label = target + /** + * Eliminates unnecessary jump instructions + * + * {{{ + * Jump l; [nops]; l: [...] + * => POP*; [nops]; l: [...] + * }}} + * + * Introduces 0, 1 or 2 POP instructions, depending on the number of values consumed by the Jump. + */ + def removeJumpToSuccessor(insn: AbstractInsnNode): Boolean = insn match { + case JumpNonJsr(jump) if nextExecutableInstruction(jump, alsoKeep = Set(jump.label)) contains jump.label => + replaceJumpByPop(jump) true - } - case _ => false - } + case _ => false + } - /** - * Eliminates unnecessary jump instructions - * - * Jump l; [nops]; l: [...] - * => POP*; [nops]; l: [...] - * - * Introduces 0, 1 or 2 POP instructions, depending on the number of values consumed by the Jump. - */ - private def removeJumpToSuccessor(method: MethodNode, instruction: AbstractInsnNode) = instruction match { - case JumpNonJsr(jump) if nextExecutableInstruction(jump, alsoKeep = Set(jump.label)) == Some(jump.label) => - removeJumpAndAdjustStack(method, jump) - true - case _ => false - } + /** + * If the "else" part of a conditional branch is a simple GOTO, negates the conditional branch + * and eliminates the GOTO. + * + * {{{ + * CondJump l; [nops, no jump targets]; GOTO m; [nops]; l: [...] + * => NegatedCondJump m; [nops, no jump targets]; [nops]; l: [...] + * }}} + * + * Note that no jump targets are allowed in the first [nops] section. Otherwise, there could + * be some other jump to the GOTO, and eliminating it would change behavior. + */ + def simplifyBranchOverGoto(insn: AbstractInsnNode, inTryBlock: Boolean): Boolean = insn match { + case ConditionalJump(jump) => + // don't skip over jump targets, see doc comment + nextExecutableInstruction(jump, alsoKeep = jumpTargets) match { + case Some(Goto(goto)) => + if (nextExecutableInstruction(goto, alsoKeep = Set(jump.label)) contains jump.label) { + val newJump = new JumpInsnNode(negateJumpOpcode(jump.getOpcode), goto.label) + method.instructions.set(jump, newJump) + removeJumpFromMap(jump) + jumpInsns(newJump) = inTryBlock + replaceJumpByPop(goto) + true + } else false + + case _ => false + } + case _ => false + } - /** - * If the "else" part of a conditional branch is a simple GOTO, negates the conditional branch - * and eliminates the GOTO. - * - * CondJump l; [nops, no labels]; GOTO m; [nops]; l: [...] - * => NegatedCondJump m; [nops, no labels]; [nops]; l: [...] - * - * Note that no label definitions are allowed in the first [nops] section. Otherwise, there could - * be some other jump to the GOTO, and eliminating it would change behavior. - * - * For technical reasons, we cannot remove the GOTO here (*).Instead this method returns an Option - * containing the GOTO that needs to be eliminated. - * - * (*) The ASM instruction iterator (used in the caller [[simplifyJumps]]) has an undefined - * behavior if the successor of the current instruction is removed, which may be the case here - */ - private def simplifyBranchOverGoto(method: MethodNode, instruction: AbstractInsnNode): Option[JumpInsnNode] = instruction match { - case ConditionalJump(jump) => - // don't skip over labels, see doc comment - nextExecutableInstruction(jump, alsoKeep = _.isInstanceOf[LabelNode]) match { - case Some(Goto(goto)) => - if (nextExecutableInstruction(goto, alsoKeep = Set(jump.label)) == Some(jump.label)) { - val newJump = new JumpInsnNode(negateJumpOpcode(jump.getOpcode), goto.label) - method.instructions.set(jump, newJump) - Some(goto) - } else None - - case _ => None - } - case _ => None - } + /** + * Inlines xRETURN and ATHROW + * + * {{{ + * GOTO l; [any ops]; l: xRETURN/ATHROW + * => xRETURN/ATHROW; [any ops]; l: xRETURN/ATHROW + * }}} + * + * inlining is only done if the GOTO instruction is not part of a try block, otherwise the + * rewrite might change the behavior. For xRETURN, the reason is that return instructions may throw + * an IllegalMonitorStateException, as described here: + * http://docs.oracle.com/javase/specs/jvms/se8/html/jvms-6.html#jvms-6.5.return + */ + def simplifyGotoReturn(instruction: AbstractInsnNode, inTryBlock: Boolean): Boolean = !inTryBlock && (instruction match { + case Goto(jump) => + nextExecutableInstruction(jump.label) match { + case Some(target) => + if (isReturn(target) || target.getOpcode == ATHROW) { + method.instructions.set(jump, target.clone(null)) + removeJumpFromMap(jump) + true + } else false + + case _ => false + } + case _ => false + }) - /** - * Inlines xRETURN and ATHROW - * - * GOTO l; [any ops]; l: xRETURN/ATHROW - * => xRETURN/ATHROW; [any ops]; l: xRETURN/ATHROW - * - * inlining is only done if the GOTO instruction is not part of a try block, otherwise the - * rewrite might change the behavior. For xRETURN, the reason is that return instructions may throw - * an IllegalMonitorStateException, as described here: - * http://docs.oracle.com/javase/specs/jvms/se8/html/jvms-6.html#jvms-6.5.return - */ - private def simplifyGotoReturn(method: MethodNode, instruction: AbstractInsnNode, inTryBlock: Boolean): Boolean = !inTryBlock && (instruction match { - case Goto(jump) => - nextExecutableInstruction(jump.label) match { - case Some(target) => - if (isReturn(target) || target.getOpcode == Opcodes.ATHROW) { - method.instructions.set(jump, target.clone(null)) - true - } else false + def run(): Boolean = { + var changed = false + + // `.toList` because we're modifying the map while iterating over it + for ((jumpInsn, inTryBlock) <- jumpInsns.toList if jumpInsns.contains(jumpInsn) && isJumpNonJsr(jumpInsn)) { + var jumpRemoved = simplifyThenElseSameTarget(jumpInsn) + + if (!jumpRemoved) { + changed = collapseJumpChains(jumpInsn) || changed + jumpRemoved = removeJumpToSuccessor(jumpInsn) + + if (!jumpRemoved) { + changed = simplifyBranchOverGoto(jumpInsn, inTryBlock) || changed + changed = simplifyGotoReturn(jumpInsn, inTryBlock) || changed + } + } - case _ => false + changed ||= jumpRemoved } - case _ => false - }) + + if (changed) run() + changed + } + + run() + } } diff --git a/src/compiler/scala/tools/nsc/backend/opt/ClosureElimination.scala b/src/compiler/scala/tools/nsc/backend/opt/ClosureElimination.scala deleted file mode 100644 index a866173a88..0000000000 --- a/src/compiler/scala/tools/nsc/backend/opt/ClosureElimination.scala +++ /dev/null @@ -1,235 +0,0 @@ - /* NSC -- new Scala compiler - * Copyright 2005-2013 LAMP/EPFL - * @author Iulian Dragos - */ - -package scala.tools.nsc -package backend.opt - -import scala.tools.nsc.backend.icode.analysis.LubException - -/** - * @author Iulian Dragos - */ -abstract class ClosureElimination extends SubComponent { - import global._ - import icodes._ - import icodes.opcodes._ - - val phaseName = "closelim" - - override val enabled: Boolean = settings.Xcloselim - - /** Create a new phase */ - override def newPhase(p: Phase) = new ClosureEliminationPhase(p) - - /** A simple peephole optimizer. */ - val peephole = new PeepholeOpt { - - def peep(bb: BasicBlock, i1: Instruction, i2: Instruction) = (i1, i2) match { - case (CONSTANT(c), DROP(_)) => - if (c.tag == UnitTag) Some(List(i2)) else Some(Nil) - - case (LOAD_LOCAL(x), STORE_LOCAL(y)) => - if (x eq y) Some(Nil) else None - - case (STORE_LOCAL(x), LOAD_LOCAL(y)) if (x == y) => - var liveOut = liveness.out(bb) - if (!liveOut(x)) { - debuglog("store/load to a dead local? " + x) - val instrs = bb.getArray - var idx = instrs.length - 1 - while (idx > 0 && (instrs(idx) ne i2)) { - liveOut = liveness.interpret(liveOut, instrs(idx)) - idx -= 1 - } - if (!liveOut(x)) { - log("Removing dead store/load of " + x.sym.initialize.defString) - Some(Nil) - } else None - } else - Some(List(DUP(x.kind), STORE_LOCAL(x))) - - case (LOAD_LOCAL(_), DROP(_)) | (DUP(_), DROP(_)) => - Some(Nil) - - case (BOX(t1), UNBOX(t2)) if (t1 == t2) => - Some(Nil) - - case (LOAD_FIELD(sym, /* isStatic */false), DROP(_)) if !sym.hasAnnotation(definitions.VolatileAttr) && inliner.isClosureClass(sym.owner) => - Some(DROP(REFERENCE(definitions.ObjectClass)) :: Nil) - - case _ => None - } - } - - /** The closure elimination phase. - */ - class ClosureEliminationPhase(prev: Phase) extends ICodePhase(prev) { - - def name = phaseName - val closser = new ClosureElim - - override def apply(c: IClass): Unit = { - if (closser ne null) - closser analyzeClass c - } - } - - /** - * Remove references to the environment through fields of a closure object. - * This has to be run after an 'apply' method has been inlined, but it still - * references the closure object. - * - */ - class ClosureElim { - def analyzeClass(cls: IClass): Unit = if (settings.Xcloselim) { - log(s"Analyzing ${cls.methods.size} methods in $cls.") - cls.methods foreach { m => - analyzeMethod(m) - peephole(m) - }} - - val cpp = new copyPropagation.CopyAnalysis - - import copyPropagation._ - - /* Some embryonic copy propagation. */ - def analyzeMethod(m: IMethod): Unit = try {if (m.hasCode) { - cpp.init(m) - cpp.run() - - m.linearizedBlocks() foreach { bb => - var info = cpp.in(bb) - debuglog("Cpp info at entry to block " + bb + ": " + info) - - for (i <- bb) { - i match { - case LOAD_LOCAL(l) if info.bindings isDefinedAt LocalVar(l) => - val t = info.getBinding(l) - t match { - case Deref(This) | Const(_) => - bb.replaceInstruction(i, valueToInstruction(t)) - debuglog(s"replaced $i with $t") - - case _ => - val t = info.getAlias(l) - bb.replaceInstruction(i, LOAD_LOCAL(t)) - debuglog(s"replaced $i with $t") - } - - case LOAD_FIELD(f, false) /* if accessible(f, m.symbol) */ => - def replaceFieldAccess(r: Record) { - val Record(cls, _) = r - info.getFieldNonRecordValue(r, f) foreach { v => - bb.replaceInstruction(i, DROP(REFERENCE(cls)) :: valueToInstruction(v) :: Nil) - debuglog(s"replaced $i with $v") - } - } - - info.stack(0) match { - case r @ Record(_, bindings) if bindings isDefinedAt f => - replaceFieldAccess(r) - - case Deref(LocalVar(l)) => - info.getBinding(l) match { - case r @ Record(_, bindings) if bindings isDefinedAt f => - replaceFieldAccess(r) - case _ => - } - case Deref(Field(r1, f1)) => - info.getFieldValue(r1, f1) match { - case Some(r @ Record(_, bindings)) if bindings isDefinedAt f => - replaceFieldAccess(r) - case _ => - } - - case _ => - } - - case UNBOX(boxType) => - info.stack match { - case Deref(LocalVar(loc1)) :: _ if info.bindings isDefinedAt LocalVar(loc1) => - val value = info.getBinding(loc1) - value match { - case Boxed(LocalVar(loc2)) if loc2.kind == boxType => - bb.replaceInstruction(i, DROP(icodes.ObjectReference) :: valueToInstruction(info.getBinding(loc2)) :: Nil) - debuglog("replaced " + i + " with " + info.getBinding(loc2)) - case _ => - () - } - case Boxed(LocalVar(loc1)) :: _ if loc1.kind == boxType => - val loc2 = info.getAlias(loc1) - bb.replaceInstruction(i, DROP(icodes.ObjectReference) :: valueToInstruction(Deref(LocalVar(loc2))) :: Nil) - debuglog("replaced " + i + " with " + LocalVar(loc2)) - case _ => - } - - case _ => - } - info = cpp.interpret(info, i) - } - } - }} catch { - case e: LubException => - Console.println("In method: " + m) - Console.println(e) - e.printStackTrace - } - - /* Partial mapping from values to instructions that load them. */ - def valueToInstruction(v: Value): Instruction = (v: @unchecked) match { - case Deref(LocalVar(v)) => - LOAD_LOCAL(v) - case Const(k) => - CONSTANT(k) - case Deref(This) => - THIS(definitions.ObjectClass) - case Boxed(LocalVar(v)) => - LOAD_LOCAL(v) - } - } /* class ClosureElim */ - - - /** Peephole optimization. */ - abstract class PeepholeOpt { - /** Concrete implementations will perform their optimizations here */ - def peep(bb: BasicBlock, i1: Instruction, i2: Instruction): Option[List[Instruction]] - - var liveness: global.icodes.liveness.LivenessAnalysis = null - - def apply(m: IMethod): Unit = if (m.hasCode) { - liveness = new global.icodes.liveness.LivenessAnalysis - liveness.init(m) - liveness.run() - m foreachBlock transformBlock - } - - def transformBlock(b: BasicBlock): Unit = if (b.size >= 2) { - var newInstructions: List[Instruction] = b.toList - var redo = false - - do { - var h = newInstructions.head - var t = newInstructions.tail - var seen: List[Instruction] = Nil - redo = false - - while (t != Nil) { - peep(b, h, t.head) match { - case Some(newInstrs) => - newInstructions = seen reverse_::: newInstrs ::: t.tail - redo = true - case None => - () - } - seen = h :: seen - h = t.head - t = t.tail - } - } while (redo) - b fromList newInstructions - } - } - -} /* class ClosureElimination */ diff --git a/src/compiler/scala/tools/nsc/backend/opt/ConstantOptimization.scala b/src/compiler/scala/tools/nsc/backend/opt/ConstantOptimization.scala deleted file mode 100644 index eafaf41932..0000000000 --- a/src/compiler/scala/tools/nsc/backend/opt/ConstantOptimization.scala +++ /dev/null @@ -1,626 +0,0 @@ -/* NSC -- new Scala compiler - * Copyright 2005-2013 LAMP/EPFL - * @author James Iry - */ - -package scala -package tools.nsc -package backend.opt - -import scala.annotation.tailrec - -/** - * ConstantOptimization uses abstract interpretation to approximate for - * each instruction what constants a variable or stack slot might hold - * or cannot hold. From this it will eliminate unreachable conditionals - * where only one branch is reachable, e.g. to eliminate unnecessary - * null checks. - * - * With some more work it could be extended to - * - cache stable values (final fields, modules) in locals - * - replace the copy propagation in ClosureElimination - * - fold constants - * - eliminate unnecessary stores and loads - * - propagate knowledge gathered from conditionals for further optimization - */ -abstract class ConstantOptimization extends SubComponent { - import global._ - import icodes._ - import icodes.opcodes._ - - val phaseName = "constopt" - - /** Create a new phase */ - override def newPhase(p: Phase) = new ConstantOptimizationPhase(p) - - override val enabled: Boolean = settings.YconstOptimization - - /** - * The constant optimization phase. - */ - class ConstantOptimizationPhase(prev: Phase) extends ICodePhase(prev) { - - def name = phaseName - - override def apply(c: IClass) { - if (settings.YconstOptimization) { - val analyzer = new ConstantOptimizer - analyzer optimizeClass c - } - } - } - - class ConstantOptimizer { - def optimizeClass(cls: IClass) { - log(s"Analyzing ${cls.methods.size} methods in $cls.") - cls.methods foreach { m => - optimizeMethod(m) - } - } - - def optimizeMethod(m: IMethod) { - if (m.hasCode) { - log(s"Analyzing ${m.symbol}") - val replacementInstructions = interpretMethod(m) - for (block <- m.blocks) { - if (replacementInstructions contains block) { - val instructions = replacementInstructions(block) - block.replaceInstruction(block.lastInstruction, instructions) - } - } - } - } - - /** - * A single possible (or impossible) datum that can be held in Contents - */ - private sealed abstract class Datum - /** - * A constant datum - */ - private case class Const(c: Constant) extends Datum { - def isIntAssignable = c.tag >= BooleanTag && c.tag <= IntTag - def toInt = c.tag match { - case BooleanTag => if (c.booleanValue) 1 else 0 - case _ => c.intValue - } - - /** - * True if this constant would compare to other as true under primitive eq - */ - override def equals(other: Any) = other match { - case oc @ Const(o) => (this eq oc) || (if (this.isIntAssignable && oc.isIntAssignable) this.toInt == oc.toInt else c.value == o.value) - case _ => false - } - - /** - * Hash code consistent with equals - */ - override def hashCode = if (this.isIntAssignable) this.toInt else c.hashCode - - } - /** - * A datum that has been Boxed via a BOX instruction - */ - private case class Boxed(c: Datum) extends Datum - - /** - * The knowledge we have about the abstract state of one location in terms - * of what constants it might or cannot hold. Forms a lower - * lattice where lower elements in the lattice indicate less knowledge. - * - * With the following partial ordering (where '>' indicates more precise knowledge) - * - * Possible(xs) > Possible(xs + y) - * Possible(xs) > Impossible(ys) - * Impossible(xs + y) > Impossible(xs) - * - * and the following merges, which indicate merging knowledge from two paths through - * the code, - * - * // left must be 1 or 2, right must be 2 or 3 then we must have a 1, 2 or 3 - * Possible(xs) merge Possible(ys) => Possible(xs union ys) - * - * // Left says can't be 2 or 3, right says can't be 3 or 4 - * // then it's not 3 (it could be 2 from the right or 4 from the left) - * Impossible(xs) merge Impossible(ys) => Impossible(xs intersect ys) - * - * // Left says it can't be 2 or 3, right says it must be 3 or 4, then - * // it can't be 2 (left rules out 4 and right says 3 is possible) - * Impossible(xs) merge Possible(ys) => Impossible(xs -- ys) - * - * Intuitively, Possible(empty) says that a location can't hold anything, - * it's uninitialized. However, Possible(empty) never appears in the code. - * - * Conversely, Impossible(empty) says nothing is impossible, it could be - * anything. Impossible(empty) is given a synonym UNKNOWN and is used - * for, e.g., the result of an arbitrary method call. - */ - private sealed abstract class Contents { - /** - * Join this Contents with another coming from another path. Join enforces - * the lattice structure. It is symmetrical and never moves upward in the - * lattice - */ - final def merge(other: Contents): Contents = if (this eq other) this else (this, other) match { - case (Possible(possible1), Possible(possible2)) => - Possible(possible1 union possible2) - case (Impossible(impossible1), Impossible(impossible2)) => - Impossible(impossible1 intersect impossible2) - case (Impossible(impossible), Possible(possible)) => - Impossible(impossible -- possible) - case (Possible(possible), Impossible(impossible)) => - Impossible(impossible -- possible) - } - // TODO we could have more fine-grained knowledge, e.g. know that 0 < x < 3. But for now equality/inequality is a good start. - def mightEqual(other: Contents): Boolean - def mightNotEqual(other: Contents): Boolean - } - private def SingleImpossible(x: Datum) = new Impossible(Set(x)) - - /** - * The location is known to have one of a set of values. - */ - private case class Possible(possible: Set[Datum]) extends Contents { - assert(possible.nonEmpty, "Contradiction: had an empty possible set indicating an uninitialized location") - def mightEqual(other: Contents): Boolean = (this eq other) || (other match { - // two Possibles might be equal if they have any possible members in common - case Possible(possible2) => (possible intersect possible2).nonEmpty - // a possible can be equal to an impossible if the impossible doesn't rule - // out all the possibilities - case Impossible(possible2) => (possible -- possible2).nonEmpty - }) - def mightNotEqual(other: Contents): Boolean = (other match { - case Possible(possible2) => - // two Possibles must equal if each is known to be of the same, single value - val mustEqual = possible.size == 1 && possible == possible2 - !mustEqual - case Impossible(_) => true - }) - } - private def SinglePossible(x: Datum) = new Possible(Set(x)) - - /** - * The location is known to not have any of a set of values value (e.g null). - */ - private case class Impossible(impossible: Set[Datum]) extends Contents { - def mightEqual(other: Contents): Boolean = (this eq other) || (other match { - case Possible(_) => other mightEqual this - case _ => true - }) - def mightNotEqual(other: Contents): Boolean = (this eq other) || (other match { - case Possible(_) => other mightNotEqual this - case _ => true - }) - } - - /** - * Our entire knowledge about the contents of all variables and the stack. It forms - * a lattice primarily driven by the lattice structure of Contents. - * - * In addition to the rules of contents, State has the following properties: - * - The merge of two sets of locals holds the merges of locals found in the intersection - * of the two sets of locals. Locals not found in a - * locals map are thus possibly uninitialized and attempting to load them results - * in an error. - * - The stack heights of two states must match otherwise it's an error to merge them - * - * State is immutable in order to aid in structure sharing of local maps and stacks - */ - private case class State(locals: Map[Local, Contents], stack: List[Contents]) { - def mergeLocals(olocals: Map[Local, Contents]): Map[Local, Contents] = if (locals eq olocals) locals else Map((for { - key <- (locals.keySet intersect olocals.keySet).toSeq - } yield (key, locals(key) merge olocals(key))): _*) - - def merge(other: State): State = if (this eq other) this else { - @tailrec def mergeStacks(l: List[Contents], r: List[Contents], out: List[Contents]): List[Contents] = (l, r) match { - case (Nil, Nil) => out.reverse - case (l, r) if l eq r => out.reverse ++ l - case (lhead :: ltail, rhead :: rtail) => mergeStacks(ltail, rtail, (lhead merge rhead) :: out) - case _ => sys.error("Mismatched stack heights") - } - - val newLocals = mergeLocals(other.locals) - - val newStack = if (stack eq other.stack) stack else mergeStacks(stack, other.stack, Nil) - State(newLocals, newStack) - } - - /** - * Peek at the top of the stack without modifying it. Error if the stack is empty - */ - def peek(n: Int): Contents = stack(n) - /** - * Push contents onto a stack - */ - def push(contents: Contents): State = this copy (stack = contents :: stack) - /** - * Drop n elements from the stack - */ - def drop(number: Int): State = this copy (stack = stack drop number) - /** - * Store the top of the stack into the specified local. An error if the stack - * is empty - */ - def store(variable: Local): State = { - val contents = stack.head - val newVariables = locals + ((variable, contents)) - new State(newVariables, stack.tail) - } - /** - * Load the specified local onto the top of the stack. An error if the local is uninitialized. - */ - def load(variable: Local): State = { - val contents: Contents = locals.getOrElse(variable, sys.error(s"$variable is not initialized")) - push(contents) - } - /** - * A copy of this State with an empty stack - */ - def cleanStack: State = if (stack.isEmpty) this else this copy (stack = Nil) - } - - // some precomputed constants - private val NULL = Const(Constant(null: Any)) - private val UNKNOWN = Impossible(Set.empty) - private val NOT_NULL = SingleImpossible(NULL) - private val CONST_UNIT = SinglePossible(Const(Constant(()))) - private val CONST_FALSE = SinglePossible(Const(Constant(false))) - private val CONST_ZERO_BYTE = SinglePossible(Const(Constant(0: Byte))) - private val CONST_ZERO_SHORT = SinglePossible(Const(Constant(0: Short))) - private val CONST_ZERO_CHAR = SinglePossible(Const(Constant(0: Char))) - private val CONST_ZERO_INT = SinglePossible(Const(Constant(0: Int))) - private val CONST_ZERO_LONG = SinglePossible(Const(Constant(0: Long))) - private val CONST_ZERO_FLOAT = SinglePossible(Const(Constant(0.0f))) - private val CONST_ZERO_DOUBLE = SinglePossible(Const(Constant(0.0d))) - private val CONST_NULL = SinglePossible(NULL) - - /** - * Given a TypeKind, figure out what '0' for it means in order to interpret CZJUMP - */ - private def getZeroOf(k: TypeKind): Contents = k match { - case UNIT => CONST_UNIT - case BOOL => CONST_FALSE - case BYTE => CONST_ZERO_BYTE - case SHORT => CONST_ZERO_SHORT - case CHAR => CONST_ZERO_CHAR - case INT => CONST_ZERO_INT - case LONG => CONST_ZERO_LONG - case FLOAT => CONST_ZERO_FLOAT - case DOUBLE => CONST_ZERO_DOUBLE - case REFERENCE(_) => CONST_NULL - case ARRAY(_) => CONST_NULL - case BOXED(_) => CONST_NULL - case ConcatClass => abort("no zero of ConcatClass") - } - - // normal locals can't be null, so we use null to mean the magic 'this' local - private val THIS_LOCAL: Local = null - - /** - * interpret a single instruction to find its impact on the abstract state - */ - private def interpretInst(in: State, inst: Instruction): State = { - // pop the consumed number of values off the `in` state's stack, producing a new state - def dropConsumed: State = in drop inst.consumed - - inst match { - case THIS(_) => - in load THIS_LOCAL - - case CONSTANT(k) => - // treat NaN as UNKNOWN because NaN must never equal NaN - val const = if (k.isNaN) UNKNOWN - else SinglePossible(Const(k)) - in push const - - case LOAD_ARRAY_ITEM(_) | LOAD_FIELD(_, _) | CALL_PRIMITIVE(_) => - dropConsumed push UNKNOWN - - case LOAD_LOCAL(local) => - // TODO if a local is known to hold a constant then we can replace this instruction with a push of that constant - in load local - - case STORE_LOCAL(local) => - in store local - - case STORE_THIS(_) => - // if a local is already known to have a constant and we're replacing with the same constant then we can - // replace this with a drop - in store THIS_LOCAL - - case CALL_METHOD(_, _) => - // TODO we could special case implementations of equals that are known, e.g. String#equals - // We could turn Possible(string constants).equals(Possible(string constants) into an eq check - // We could turn nonConstantString.equals(constantString) into constantString.equals(nonConstantString) - // and eliminate the null check that likely precedes this call - val initial = dropConsumed - (0 until inst.produced).foldLeft(initial) { case (know, _) => know push UNKNOWN } - - case BOX(_) => - val value = in peek 0 - // we simulate boxing by, um, boxing the possible/impossible contents - // so if we have Possible(1,2) originally then we'll end up with - // a Possible(Boxed(1), Boxed(2)) - // Similarly, if we know the input is not a 0 then we'll know the - // output is not a Boxed(0) - val newValue = value match { - case Possible(values) => Possible(values map Boxed) - case Impossible(values) => Impossible(values map Boxed) - } - dropConsumed push newValue - - case UNBOX(_) => - val value = in peek 0 - val newValue = value match { - // if we have a Possible, then all the possibilities - // should themselves be Boxes. In that - // case we can merge them to figure out what the UNBOX will produce - case Possible(inners) => - assert(inners.nonEmpty, "Empty possible set indicating an uninitialized location") - val sanitized: Set[Contents] = (inners map { - case Boxed(content) => SinglePossible(content) - case _ => UNKNOWN - }) - sanitized reduce (_ merge _) - // if we have an impossible then the thing that's impossible - // should be a box. We'll unbox that to see what we get - case unknown@Impossible(inners) => - if (inners.isEmpty) { - unknown - } else { - val sanitized: Set[Contents] = (inners map { - case Boxed(content) => SingleImpossible(content) - case _ => UNKNOWN - }) - sanitized reduce (_ merge _) - } - } - dropConsumed push newValue - - case LOAD_MODULE(_) | NEW(_) | LOAD_EXCEPTION(_) => - in push NOT_NULL - - case CREATE_ARRAY(_, _) => - dropConsumed push NOT_NULL - - case IS_INSTANCE(_) => - // TODO IS_INSTANCE is going to be followed by a C(Z)JUMP - // and if IS_INSTANCE/C(Z)JUMP the branch for "true" can - // know that whatever was checked was not a null - // see the TODO on CJUMP for more information about propagating null - // information - // TODO if the top of stack is guaranteed null then we can eliminate this IS_INSTANCE check and - // replace with a constant false, but how often is a knowable null checked for instanceof? - // TODO we could track type information and statically know to eliminate IS_INSTANCE - // which might be a nice win under specialization - dropConsumed push UNKNOWN // it's actually a Possible(true, false) but since the following instruction - // will be a conditional jump comparing to true or false there - // nothing to be gained by being more precise - - case CHECK_CAST(_) => - // TODO we could track type information and statically know to eliminate CHECK_CAST - // but that's probably not a huge win - in - - case DUP(_) => - val value = in peek 0 - in push value - - case DROP(_) | MONITOR_ENTER() | MONITOR_EXIT() | STORE_ARRAY_ITEM(_) | STORE_FIELD(_, _) => - dropConsumed - - case SCOPE_ENTER(_) | SCOPE_EXIT(_) => - in - - case JUMP(_) | CJUMP(_, _, _, _) | CZJUMP(_, _, _, _) | RETURN(_) | THROW(_) | SWITCH(_, _) => - dumpClassesAndAbort("Unexpected block ending instruction: " + inst) - } - } - /** - * interpret the last instruction of a block which will be jump, a conditional branch, a throw, or a return. - * It will result in a map from target blocks to the input state computed for that block. It - * also computes a replacement list of instructions - */ - private def interpretLast(in: State, inst: Instruction): (Map[BasicBlock, State], List[Instruction]) = { - def canSwitch(in1: Contents, tagSet: List[Int]) = { - in1 mightEqual Possible(tagSet.toSet map { tag: Int => Const(Constant(tag)) }) - } - - /* common code for interpreting CJUMP and CZJUMP */ - def interpretConditional(kind: TypeKind, val1: Contents, val2: Contents, success: BasicBlock, failure: BasicBlock, cond: TestOp): (Map[BasicBlock, State], List[Instruction]) = { - // TODO use reaching analysis to update the state in the two branches - // e.g. if the comparison was checking null equality on local x - // then the in the success branch we know x is null and - // on the failure branch we know it is not - // in fact, with copy propagation we could propagate that knowledge - // back through a chain of locations - // - // TODO if we do all that we need to be careful in the - // case that success and failure are the same target block - // because we're using a Map and don't want one possible state to clobber the other - // alternative maybe we should just replace the conditional with a jump if both targets are the same - - def mightEqual = val1 mightEqual val2 - def mightNotEqual = val1 mightNotEqual val2 - def guaranteedEqual = mightEqual && !mightNotEqual - - def succPossible = cond match { - case EQ => mightEqual - case NE => mightNotEqual - case LT | GT => !guaranteedEqual // if the two are guaranteed to be equal then they can't be LT/GT - case LE | GE => true - } - - def failPossible = cond match { - case EQ => mightNotEqual - case NE => mightEqual - case LT | GT => true - case LE | GE => !guaranteedEqual // if the two are guaranteed to be equal then they must be LE/GE - } - - val out = in drop inst.consumed - - var result = Map[BasicBlock, State]() - if (succPossible) { - result += ((success, out)) - } - - if (failPossible) { - result += ((failure, out)) - } - - val replacements = if (result.size == 1) List.fill(inst.consumed)(DROP(kind)) :+ JUMP(result.keySet.head) - else inst :: Nil - - (result, replacements) - } - - inst match { - case JUMP(whereto) => - (Map((whereto, in)), inst :: Nil) - - case CJUMP(success, failure, cond, kind) => - val in1 = in peek 0 - val in2 = in peek 1 - interpretConditional(kind, in1, in2, success, failure, cond) - - case CZJUMP(success, failure, cond, kind) => - val in1 = in peek 0 - val in2 = getZeroOf(kind) - interpretConditional(kind, in1, in2, success, failure, cond) - - case SWITCH(tags, labels) => - val in1 = in peek 0 - val reachableNormalLabels = tags zip labels collect { case (tagSet, label) if canSwitch(in1, tagSet) => label } - val reachableLabels = if (tags.isEmpty) { - assert(labels.size == 1, s"When SWITCH node has empty array of tags it should have just one (default) label: $labels") - labels - } else if (labels.lengthCompare(tags.length) > 0) { - // if we've got an extra label then it's the default - val defaultLabel = labels.last - // see if the default is reachable by seeing if the input might be out of the set - // of all tags - val allTags = Possible(tags.flatten.toSet map { tag: Int => Const(Constant(tag)) }) - if (in1 mightNotEqual allTags) { - reachableNormalLabels :+ defaultLabel - } else { - reachableNormalLabels - } - } else { - reachableNormalLabels - } - // TODO similar to the comment in interpretConditional, we should update our the State going into each - // branch based on which tag is being matched. Also, just like interpretConditional, if target blocks - // are the same we need to merge State rather than clobber - - // alternative, maybe we should simplify the SWITCH to not have same target labels - val newState = in drop inst.consumed - val result = Map(reachableLabels map { label => (label, newState) }: _*) - if (reachableLabels.size == 1) (result, DROP(INT) :: JUMP(reachableLabels.head) :: Nil) - else (result, inst :: Nil) - - // these instructions don't have target blocks - // (exceptions are assumed to be reachable from all instructions) - case RETURN(_) | THROW(_) => - (Map.empty, inst :: Nil) - - case _ => - dumpClassesAndAbort("Unexpected non-block ending instruction: " + inst) - } - } - - /** - * Analyze a single block to find how it transforms an input state into a states for its successor blocks - * Also computes a list of instructions to be used to replace its last instruction - */ - private def interpretBlock(in: State, block: BasicBlock): (Map[BasicBlock, State], Map[BasicBlock, State], List[Instruction]) = { - debuglog(s"interpreting block $block") - // number of instructions excluding the last one - val normalCount = block.size - 1 - - var exceptionState = in.cleanStack - var normalExitState = in - var idx = 0 - while (idx < normalCount) { - val inst = block(idx) - normalExitState = interpretInst(normalExitState, inst) - if (normalExitState.locals ne exceptionState.locals) - exceptionState = exceptionState.copy(locals = exceptionState mergeLocals normalExitState.locals) - idx += 1 - } - - val pairs = block.exceptionSuccessors map { b => (b, exceptionState) } - val exceptionMap = Map(pairs: _*) - - val (normalExitMap, newInstructions) = interpretLast(normalExitState, block.lastInstruction) - - (normalExitMap, exceptionMap, newInstructions) - } - - /** - * Analyze a single method to find replacement instructions - */ - private def interpretMethod(m: IMethod): Map[BasicBlock, List[Instruction]] = { - import scala.collection.mutable.{ Set => MSet, Map => MMap } - - debuglog(s"interpreting method $m") - var iterations = 0 - - // initially we know that 'this' is not null and the params are initialized to some unknown value - val initThis: Iterator[(Local, Contents)] = if (m.isStatic) Iterator.empty else Iterator.single((THIS_LOCAL, NOT_NULL)) - val initOtherLocals: Iterator[(Local, Contents)] = m.params.iterator map { param => (param, UNKNOWN) } - val initialLocals: Map[Local, Contents] = Map((initThis ++ initOtherLocals).toSeq: _*) - val initialState = State(initialLocals, Nil) - - // worklist of basic blocks to process, initially the start block - val worklist = MSet(m.startBlock) - // worklist of exception basic blocks. They're kept in a separate set so they can be - // processed after normal flow basic blocks. That's because exception basic blocks - // are more likely to have multiple predecessors and queueing them for later - // increases the chances that they'll only need to be interpreted once - val exceptionlist = MSet[BasicBlock]() - // our current best guess at what the input state is for each block - // initially we only know about the start block - val inputState = MMap[BasicBlock, State]((m.startBlock, initialState)) - - // update the inputState map based on new information from interpreting a block - // When the input state of a block changes, add it back to the work list to be - // reinterpreted - def updateInputStates(outputStates: Map[BasicBlock, State], worklist: MSet[BasicBlock]) { - for ((block, newState) <- outputStates) { - val oldState = inputState get block - val updatedState = oldState map (x => x merge newState) getOrElse newState - if (oldState != Some(updatedState)) { - worklist add block - inputState(block) = updatedState - } - } - } - - // the instructions to be used as the last instructions on each block - val replacements = MMap[BasicBlock, List[Instruction]]() - - while (worklist.nonEmpty || exceptionlist.nonEmpty) { - if (worklist.isEmpty) { - // once the worklist is empty, start processing exception blocks - val block = exceptionlist.head - exceptionlist remove block - worklist add block - } else { - iterations += 1 - val block = worklist.head - worklist remove block - val (normalExitMap, exceptionMap, newInstructions) = interpretBlock(inputState(block), block) - - updateInputStates(normalExitMap, worklist) - updateInputStates(exceptionMap, exceptionlist) - replacements(block) = newInstructions - } - } - - debuglog(s"method $m with ${m.blocks.size} reached fixpoint in $iterations iterations") - replacements.toMap - } - } -} diff --git a/src/compiler/scala/tools/nsc/backend/opt/DeadCodeElimination.scala b/src/compiler/scala/tools/nsc/backend/opt/DeadCodeElimination.scala deleted file mode 100644 index 8911a3a28c..0000000000 --- a/src/compiler/scala/tools/nsc/backend/opt/DeadCodeElimination.scala +++ /dev/null @@ -1,450 +0,0 @@ -/* NSC -- new scala compiler - * Copyright 2005-2013 LAMP/EPFL - * @author Iulian Dragos - */ - - -package scala.tools.nsc -package backend.opt - -import scala.collection.{ mutable, immutable } - -/** - */ -abstract class DeadCodeElimination extends SubComponent { - import global._ - import icodes._ - import icodes.opcodes._ - import definitions.RuntimePackage - - /** The block and index where an instruction is located */ - type InstrLoc = (BasicBlock, Int) - - val phaseName = "dce" - - override val enabled: Boolean = settings.Xdce - - /** Create a new phase */ - override def newPhase(p: Phase) = new DeadCodeEliminationPhase(p) - - /** Dead code elimination phase. - */ - class DeadCodeEliminationPhase(prev: Phase) extends ICodePhase(prev) { - - def name = phaseName - val dce = new DeadCode() - - override def apply(c: IClass) { - if (settings.Xdce && (dce ne null)) - dce.analyzeClass(c) - } - } - - /** closures that are instantiated at least once, after dead code elimination */ - val liveClosures = perRunCaches.newSet[Symbol]() - - /** closures that are eliminated, populated by GenASM.AsmPhase.run() - * these class symbols won't have a .class physical file, thus shouldn't be included in InnerClasses JVM attribute, - * otherwise some tools get confused or slow (SI-6546) - * */ - val elidedClosures = perRunCaches.newSet[Symbol]() - - /** Remove dead code. - */ - class DeadCode { - - def analyzeClass(cls: IClass) { - log(s"Analyzing ${cls.methods.size} methods in $cls.") - cls.methods.foreach { m => - this.method = m - dieCodeDie(m) - global.closureElimination.peephole(m) - } - } - - val rdef = new reachingDefinitions.ReachingDefinitionsAnalysis - - /** Use-def chain: give the reaching definitions at the beginning of given instruction. */ - var defs: immutable.Map[InstrLoc, immutable.Set[rdef.lattice.Definition]] = immutable.HashMap.empty - - /** Useful instructions which have not been scanned yet. */ - val worklist: mutable.Set[InstrLoc] = new mutable.LinkedHashSet - - /** what instructions have been marked as useful? */ - val useful: mutable.Map[BasicBlock, mutable.BitSet] = perRunCaches.newMap() - - /** what local variables have been accessed at least once? */ - var accessedLocals: List[Local] = Nil - - /** Map from a local and a basic block to the instructions that store to that local in that basic block */ - val localStores = mutable.Map[(Local, BasicBlock), mutable.BitSet]() withDefault {_ => mutable.BitSet()} - - /** Stores that clobber previous stores to array or ref locals. See SI-5313 */ - val clobbers = mutable.Set[InstrLoc]() - - /** the current method. */ - var method: IMethod = _ - - /** Map instructions who have a drop on some control path, to that DROP instruction. */ - val dropOf: mutable.Map[InstrLoc, List[InstrLoc]] = perRunCaches.newMap() - - def dieCodeDie(m: IMethod) { - if (m.hasCode) { - debuglog("dead code elimination on " + m) - dropOf.clear() - localStores.clear() - clobbers.clear() - m.code.blocks.clear() - m.code.touched = true - accessedLocals = m.params.reverse - m.code.blocks ++= linearizer.linearize(m) - m.code.touched = true - collectRDef(m) - mark() - sweep(m) - accessedLocals = accessedLocals.distinct - val diff = m.locals diff accessedLocals - if (diff.nonEmpty) { - val msg = diff.map(_.sym.name)mkString(", ") - log(s"Removed ${diff.size} dead locals: $msg") - m.locals = accessedLocals.reverse - } - } - } - - /** collect reaching definitions and initial useful instructions for this method. */ - def collectRDef(m: IMethod): Unit = if (m.hasCode) { - defs = immutable.HashMap.empty; worklist.clear(); useful.clear() - rdef.init(m) - rdef.run() - - m foreachBlock { bb => - useful(bb) = new mutable.BitSet(bb.size) - var rd = rdef.in(bb) - for ((i, idx) <- bb.toList.zipWithIndex) { - - // utility for adding to worklist - def moveToWorkList() = moveToWorkListIf(cond = true) - - // utility for (conditionally) adding to worklist - def moveToWorkListIf(cond: Boolean) = - if (cond) { - debuglog("in worklist: " + i) - worklist += ((bb, idx)) - } else { - debuglog("not in worklist: " + i) - } - - // instruction-specific logic - i match { - - case LOAD_LOCAL(_) => - defs = defs + (((bb, idx), rd.vars)) - moveToWorkListIf(cond = false) - - case STORE_LOCAL(l) => - /* SI-4935 Check whether a module is stack top, if so mark the instruction that loaded it - * (otherwise any side-effects of the module's constructor go lost). - * (a) The other two cases where a module's value is stored (STORE_FIELD and STORE_ARRAY_ITEM) - * are already marked (case clause below). - * (b) A CALL_METHOD targeting a method `m1` where the receiver is potentially a module (case clause below) - * will have the module's load marked provided `isSideEffecting(m1)`. - * TODO check for purity (the ICode?) of the module's constructor (besides m1's purity). - * See also https://github.com/paulp/scala/blob/topic/purity-analysis/src/compiler/scala/tools/nsc/backend/opt/DeadCodeElimination.scala - */ - val necessary = rdef.findDefs(bb, idx, 1) exists { p => - val (bb1, idx1) = p - bb1(idx1) match { - case LOAD_MODULE(module) => isLoadNeeded(module) - case _ => false - } - } - moveToWorkListIf(necessary) - - // add it to the localStores map - val key = (l, bb) - val set = localStores(key) - set += idx - localStores(key) = set - - case RETURN(_) | JUMP(_) | CJUMP(_, _, _, _) | CZJUMP(_, _, _, _) | STORE_FIELD(_, _) | - THROW(_) | LOAD_ARRAY_ITEM(_) | STORE_ARRAY_ITEM(_) | SCOPE_ENTER(_) | SCOPE_EXIT(_) | STORE_THIS(_) | - LOAD_EXCEPTION(_) | SWITCH(_, _) | MONITOR_ENTER() | MONITOR_EXIT() | CHECK_CAST(_) | CREATE_ARRAY(_, _) => - moveToWorkList() - - case LOAD_FIELD(sym, isStatic) if isStatic || !inliner.isClosureClass(sym.owner) => - // static load may trigger static initialization. - // non-static load can throw NPE (but we know closure fields can't be accessed via a - // null reference. - moveToWorkList() - case CALL_METHOD(m1, _) if isSideEffecting(m1) => - moveToWorkList() - - case CALL_METHOD(m1, SuperCall(_)) => - moveToWorkList() // super calls to constructor - - case DROP(_) => - val necessary = rdef.findDefs(bb, idx, 1) exists { p => - val (bb1, idx1) = p - bb1(idx1) match { - case CALL_METHOD(m1, _) if isSideEffecting(m1) => true - case LOAD_EXCEPTION(_) | DUP(_) | LOAD_MODULE(_) => true - case _ => - dropOf((bb1, idx1)) = (bb,idx) :: dropOf.getOrElse((bb1, idx1), Nil) - debuglog("DROP is inessential: " + i + " because of: " + bb1(idx1) + " at " + bb1 + ":" + idx1) - false - } - } - moveToWorkListIf(necessary) - case LOAD_MODULE(sym) if isLoadNeeded(sym) => - moveToWorkList() // SI-4859 Module initialization might side-effect. - case CALL_PRIMITIVE(Arithmetic(DIV | REM, INT | LONG) | ArrayLength(_)) => - moveToWorkList() // SI-8601 Might divide by zero - case _ => () - moveToWorkListIf(cond = false) - } - rd = rdef.interpret(bb, idx, rd) - } - } - } - - private def isLoadNeeded(module: Symbol): Boolean = { - module.info.member(nme.CONSTRUCTOR).filter(isSideEffecting) != NoSymbol - } - - /** Mark useful instructions. Instructions in the worklist are each inspected and their - * dependencies are marked useful too, and added to the worklist. - */ - def mark() { -// log("Starting with worklist: " + worklist) - while (!worklist.isEmpty) { - val (bb, idx) = worklist.head - worklist -= ((bb, idx)) - debuglog("Marking instr: \tBB_" + bb + ": " + idx + " " + bb(idx)) - - val instr = bb(idx) - // adds the instructions that define the stack values about to be consumed to the work list to - // be marked useful - def addDefs() = for ((bb1, idx1) <- rdef.findDefs(bb, idx, instr.consumed) if !useful(bb1)(idx1)) { - debuglog(s"\t${bb1(idx1)} is consumed by $instr") - worklist += ((bb1, idx1)) - } - - // DROP logic -- if an instruction is useful, its drops are also useful - // and we don't mark the DROPs as useful directly but add them to the - // worklist so we also mark their reaching defs as useful - see SI-7060 - if (!useful(bb)(idx)) { - useful(bb) += idx - dropOf.get((bb, idx)) foreach { - for ((bb1, idx1) <- _) { - /* - * SI-7060: A drop that we now mark as useful can be reached via several paths, - * so we should follow by marking all its reaching definition as useful too: - */ - debuglog("\tAdding: " + bb1(idx1) + " to the worklist, as a useful DROP.") - worklist += ((bb1, idx1)) - } - } - - // per-instruction logic - instr match { - case LOAD_LOCAL(l1) => - for ((l2, bb1, idx1) <- defs((bb, idx)) if l1 == l2; if !useful(bb1)(idx1)) { - debuglog("\tAdding " + bb1(idx1)) - worklist += ((bb1, idx1)) - } - - case STORE_LOCAL(l1) if l1.kind.isRefOrArrayType => - addDefs() - // see SI-5313 - // search for clobbers of this store if we aren't doing l1 = null - // this doesn't catch the second store in x=null;l1=x; but in practice this catches - // a lot of null stores very cheaply - if (idx == 0 || bb(idx - 1) != CONSTANT(Constant(null))) - findClobbers(l1, bb, idx + 1) - - case nw @ NEW(REFERENCE(sym)) => - assert(nw.init ne null, "null new.init at: " + bb + ": " + idx + "(" + instr + ")") - worklist += findInstruction(bb, nw.init) - if (inliner.isClosureClass(sym)) { - liveClosures += sym - } - - // it may be better to move static initializers from closures to - // the enclosing class, to allow the optimizer to remove more closures. - // right now, the only static fields in closures are created when caching - // 'symbol literals. - case LOAD_FIELD(sym, true) if inliner.isClosureClass(sym.owner) => - log("added closure class for field " + sym) - liveClosures += sym.owner - - case LOAD_EXCEPTION(_) => - () - - case _ => - addDefs() - } - } - } - } - - /** - * Finds and marks all clobbers of the given local starting in the given - * basic block at the given index - * - * Storing to local variables of reference or array type may be indirectly - * observable because it may remove a reference to an object which may allow the object - * to be gc'd. See SI-5313. In this code I call the LOCAL_STORE(s) that immediately follow a - * LOCAL_STORE and that store to the same local "clobbers." If a LOCAL_STORE is marked - * useful then its clobbers must go into the set of clobbers, which will be - * compensated for later - */ - def findClobbers(l: Local, bb: BasicBlock, idx: Int) { - // previously visited blocks tracked to prevent searching forever in a cycle - val inspected = mutable.Set[BasicBlock]() - // our worklist of blocks that still need to be checked - val blocksToBeInspected = mutable.Set[BasicBlock]() - - // Tries to find the next clobber of l1 in bb1 starting at idx1. - // if it finds one it adds the clobber to clobbers set for later - // handling. If not it adds the direct successor blocks to - // the uninspectedBlocks to try to find clobbers there. Either way - // it adds the exception successor blocks for further search - def findClobberInBlock(idx1: Int, bb1: BasicBlock) { - val key = ((l, bb1)) - val foundClobber = (localStores contains key) && { - def minIdx(s : mutable.BitSet) = if(s.isEmpty) -1 else s.min - - // find the smallest index greater than or equal to idx1 - val clobberIdx = minIdx(localStores(key) dropWhile (_ < idx1)) - if (clobberIdx == -1) - false - else { - debuglog(s"\t${bb1(clobberIdx)} is a clobber of ${bb(idx)}") - clobbers += ((bb1, clobberIdx)) - true - } - } - - // always need to look into the exception successors for additional clobbers - // because we don't know when flow might enter an exception handler - blocksToBeInspected ++= (bb1.exceptionSuccessors filterNot inspected) - // If we didn't find a clobber here then we need to look at successor blocks. - // if we found a clobber then we don't need to search in the direct successors - if (!foundClobber) { - blocksToBeInspected ++= (bb1.directSuccessors filterNot inspected) - } - } - - // first search starting at the current index - // note we don't put bb in the inspected list yet because a loop may later force - // us back around to search from the beginning of bb - findClobberInBlock(idx, bb) - // then loop until we've exhausted the set of uninspected blocks - while(!blocksToBeInspected.isEmpty) { - val bb1 = blocksToBeInspected.head - blocksToBeInspected -= bb1 - inspected += bb1 - findClobberInBlock(0, bb1) - } - } - - def sweep(m: IMethod) { - val compensations = computeCompensations(m) - - debuglog("Sweeping: " + m) - - m foreachBlock { bb => - debuglog(bb + ":") - val oldInstr = bb.toList - bb.open() - bb.clear() - for ((i, idx) <- oldInstr.zipWithIndex) { - if (useful(bb)(idx)) { - debuglog(" * " + i + " is useful") - bb.emit(i, i.pos) - compensations.get((bb, idx)) match { - case Some(is) => is foreach bb.emit - case None => () - } - // check for accessed locals - i match { - case LOAD_LOCAL(l) if !l.arg => - accessedLocals = l :: accessedLocals - case STORE_LOCAL(l) if !l.arg => - accessedLocals = l :: accessedLocals - case _ => () - } - } else { - i match { - case NEW(REFERENCE(sym)) => - log(s"Eliminated instantiation of $sym inside $m") - case STORE_LOCAL(l) if clobbers contains ((bb, idx)) => - // if an unused instruction was a clobber of a used store to a reference or array type - // then we'll replace it with the store of a null to make sure the reference is - // eliminated. See SI-5313 - bb emit CONSTANT(Constant(null)) - bb emit STORE_LOCAL(l) - case _ => () - } - debuglog(" " + i + " [swept]") - } - } - - if (bb.nonEmpty) bb.close() - else log(s"empty block encountered in $m") - } - } - - private def computeCompensations(m: IMethod): mutable.Map[InstrLoc, List[Instruction]] = { - val compensations: mutable.Map[InstrLoc, List[Instruction]] = new mutable.HashMap - - m foreachBlock { bb => - assert(bb.closed, "Open block in computeCompensations") - foreachWithIndex(bb.toList) { (i, idx) => - if (!useful(bb)(idx)) { - foreachWithIndex(i.consumedTypes.reverse) { (consumedType, depth) => - debuglog("Finding definitions of: " + i + "\n\t" + consumedType + " at depth: " + depth) - val defs = rdef.findDefs(bb, idx, 1, depth) - for (d <- defs) { - val (bb, idx) = d - debuglog("rdef: "+ bb(idx)) - bb(idx) match { - case DUP(_) if idx > 0 => - bb(idx - 1) match { - case nw @ NEW(_) => - val init = findInstruction(bb, nw.init) - log("Moving DROP to after <init> call: " + nw.init) - compensations(init) = List(DROP(consumedType)) - case _ => - compensations(d) = List(DROP(consumedType)) - } - case _ => - compensations(d) = List(DROP(consumedType)) - } - } - } - } - } - } - compensations - } - - private def findInstruction(bb: BasicBlock, i: Instruction): InstrLoc = { - for (b <- linearizer.linearizeAt(method, bb)) { - val idx = b.toList indexWhere (_ eq i) - if (idx != -1) - return (b, idx) - } - abort("could not find init in: " + method) - } - - private def isPure(sym: Symbol) = ( - (sym.isGetter && sym.isEffectivelyFinalOrNotOverridden && !sym.isLazy) - || (sym.isPrimaryConstructor && (sym.enclosingPackage == RuntimePackage || inliner.isClosureClass(sym.owner))) - ) - /** Is 'sym' a side-effecting method? TODO: proper analysis. */ - private def isSideEffecting(sym: Symbol) = !isPure(sym) - - } /* DeadCode */ -} diff --git a/src/compiler/scala/tools/nsc/backend/opt/InlineExceptionHandlers.scala b/src/compiler/scala/tools/nsc/backend/opt/InlineExceptionHandlers.scala deleted file mode 100644 index 9f6883f03f..0000000000 --- a/src/compiler/scala/tools/nsc/backend/opt/InlineExceptionHandlers.scala +++ /dev/null @@ -1,392 +0,0 @@ -/* NSC -- new scala compiler - * Copyright 2005-2013 LAMP/EPFL - */ - -package scala.tools.nsc -package backend.opt - -import java.util.concurrent.TimeUnit - -/** - * This optimization phase inlines the exception handlers so that further phases can optimize the code better - * - * {{{ - * try { - * ... - * if (condition) - * throw IllegalArgumentException("sth") - * } catch { - * case e: IllegalArgumentException => <handler code> - * case e: ... => ... - * } - * }}} - * - * will inline the exception handler code to: - * - * {{{ - * try { - * ... - * if (condition) - * <handler code> // + jump to the end of the catch statement - * } catch { - * case e: IllegalArgumentException => <handler code> - * case e: ... => ... - * } - * }}} - * - * Q: How does the inlining work, ICode level? - * A: if a block contains a THROW(A) instruction AND there is a handler that takes A or a superclass of A we do: - * 1. We duplicate the handler code such that we can transform THROW into a JUMP - * 2. We analyze the handler to see what local it expects the exception to be placed in - * 3. We place the exception that is thrown in the correct "local variable" slot and clean up the stack - * 4. We finally JUMP to the duplicate handler - * All the above logic is implemented in InlineExceptionHandlersPhase.apply(bblock: BasicBlock) - * - * Q: Why do we need to duplicate the handler? - * A: An exception might be thrown in a method that we invoke in the function and we cannot see that THROW command - * directly. In order to catch such exceptions, we keep the exception handler in place and duplicate it in order - * to inline its code. - * - * @author Vlad Ureche - */ -abstract class InlineExceptionHandlers extends SubComponent { - import global._ - import icodes._ - import icodes.opcodes._ - - val phaseName = "inlinehandlers" - - /** Create a new phase */ - override def newPhase(p: Phase) = new InlineExceptionHandlersPhase(p) - - override def enabled = settings.inlineHandlers - - /** - * Inlining Exception Handlers - */ - class InlineExceptionHandlersPhase(prev: Phase) extends ICodePhase(prev) { - def name = phaseName - - /* This map is used to keep track of duplicated exception handlers - * explanation: for each exception handler basic block, there is a copy of it - * -some exception handler basic blocks might not be duplicated because they have an unknown format => Option[(...)] - * -some exception handler duplicates expect the exception on the stack while others expect it in a local - * => Option[Local] - */ - private val handlerCopies = perRunCaches.newMap[BasicBlock, Option[(Option[Local], BasicBlock)]]() - /* This map is the inverse of handlerCopies, used to compute the stack of duplicate blocks */ - private val handlerCopiesInverted = perRunCaches.newMap[BasicBlock, (BasicBlock, TypeKind)]() - private def handlerLocal(bb: BasicBlock): Option[Local] = - for (v <- handlerCopies get bb ; (local, block) <- v ; l <- local) yield l - - /* Type Flow Analysis */ - private val tfa: analysis.MethodTFA = new analysis.MethodTFA() - private var tfaCache: Map[Int, tfa.lattice.Elem] = Map.empty - private var analyzedMethod: IMethod = NoIMethod - - /* Blocks that need to be analyzed */ - private var todoBlocks: List[BasicBlock] = Nil - - /* Used only for warnings */ - private var currentClass: IClass = null - - /** Apply exception handler inlining to a class */ - override def apply(c: IClass): Unit = - if (settings.inlineHandlers) { - val startTime = System.nanoTime() - currentClass = c - - debuglog("Starting InlineExceptionHandlers on " + c) - c.methods foreach applyMethod - debuglog("Finished InlineExceptionHandlers on " + c + "... " + TimeUnit.NANOSECONDS.toMillis(System.nanoTime() - startTime) + "ms") - currentClass = null - } - - /** - * Apply exception handler inlining to a method - * - * Note: for each exception handling block, we (might) create duplicates. Therefore we iterate until we get to a - * fixed point where all the possible handlers have been inlined. - * - * TODO: Should we have an inlining depth limit? A nested sequence of n try-catch blocks can lead to at most 2n - * inlined blocks, so worst case scenario we double the size of the code - */ - private def applyMethod(method: IMethod): Unit = { - if (method.hasCode) { - // create the list of starting blocks - todoBlocks = global.icodes.linearizer.linearize(method) - - while (todoBlocks.nonEmpty) { - val levelBlocks = todoBlocks - todoBlocks = Nil - levelBlocks foreach applyBasicBlock // new blocks will be added to todoBlocks - } - } - - // Cleanup the references after we finished the file - handlerCopies.clear() - handlerCopiesInverted.clear() - todoBlocks = Nil - - // Type flow analysis cleanup - analyzedMethod = NoIMethod - tfaCache = Map.empty - //TODO: Need a way to clear tfa structures - } - - /** Apply exception handler inlining to a basic block */ - private def applyBasicBlock(bblock: BasicBlock): Unit = { - /* - * The logic of this entire method: - * - for each basic block, we look at each instruction until we find a THROW instruction - * - once we found a THROW instruction, we decide if it is DECIDABLE which of handler will catch the exception - * (see method findExceptionHandler for more details) - * - if we decided there is a handler that will catch the exception, we need to replace the THROW instruction by - * a set of equivalent instructions: - * * we need to compute the static types of the stack slots - * * we need to clear the stack, everything but the exception instance on top (or in a local variable slot) - * * we need to JUMP to the duplicate exception handler - * - we compute the static types of the stack slots in function getTypesAtInstruction - * - we duplicate the exception handler (and we get back the information of whether the duplicate expects the - * exception instance on top of the stack or in a local variable slot) - * - we compute the necessary code to put the exception in its place, clear the stack and JUMP - * - we change the THROW exception to the new Clear stack + JUMP code - */ - for { - (instr @ THROW(clazz), index) <- bblock.iterator.zipWithIndex - // Decide if any handler fits this exception - // If not, then nothing to do, we cannot determine statically which handler will catch the exception - (handler, caughtException) <- findExceptionHandler(toTypeKind(clazz.tpe), bblock.exceptionSuccessors) - } { - log(" Replacing " + instr + " in " + bblock + " to new handler") - - // Solve the stack and drop the element that we already stored, which should be the exception - // needs to be done here to be the first thing before code becomes altered - val typeInfo = getTypesAtInstruction(bblock, index) - - // Duplicate exception handler - duplicateExceptionHandlerCache(handler) match { - case None => - log(" Could not duplicate handler for " + instr + " in " + bblock) - - case Some((exceptionLocalOpt, newHandler)) => - val onStackException = typeInfo.head - val thrownException = toTypeKind(clazz.tpe) - - // A couple of sanity checks, to make sure we don't touch code we can't safely handle - val canReplaceHandler = ( - typeInfo.nonEmpty - && (index == bblock.length - 1) - && (onStackException <:< thrownException) - ) - // in other words: what's on the stack MUST conform to what's in the THROW(..)! - - if (!canReplaceHandler) { - reporter.warning(NoPosition, "Unable to inline the exception handler inside incorrect" + - " block:\n" + bblock.iterator.mkString("\n") + "\nwith stack: " + typeInfo + " just " + - "before instruction index " + index) - } - else { - // Prepare the new code to replace the THROW instruction - val newCode = exceptionLocalOpt match { - // the handler duplicate expects the exception in a local: easy one :) - case Some(local) => - // in the first cycle we remove the exception Type - STORE_LOCAL(local) +: typeInfo.tail.map(x => DROP(x)) :+ JUMP(newHandler) - - // we already have the exception on top of the stack, only need to JUMP - case None if typeInfo.length == 1 => - JUMP(newHandler) :: Nil - - // we have the exception on top of the stack but we have other stuff on the stack - // create a local, load exception, clear the stack and finally store the exception on the stack - case _ => - val exceptionType = typeInfo.head - // Here we could create a single local for all exceptions of a certain type. TODO: try that. - val localName = currentClass.cunit.freshTermName("exception$") - val localType = exceptionType - val localSymbol = bblock.method.symbol.newValue(localName).setInfo(localType.toType) - val local = new Local(localSymbol, localType, false) - - bblock.method.addLocal(local) - - // Save the exception, drop the stack and place back the exception - STORE_LOCAL(local) :: typeInfo.tail.map(x => DROP(x)) ::: List(LOAD_LOCAL(local), JUMP(newHandler)) - } - // replace THROW by the new code - bblock.replaceInstruction(instr, newCode) - - // notify the successors changed for the current block - // notify the predecessors changed for the inlined handler block - bblock.touched = true - newHandler.touched = true - - log(" Replaced " + instr + " in " + bblock + " to new handler") - log("OPTIMIZED class " + currentClass + " method " + - bblock.method + " block " + bblock + " newhandler " + - newHandler + ":\n\t\t" + onStackException + " <:< " + - thrownException + " <:< " + caughtException) - - } - } - } - } - - /** - * Gets the types on the stack at a certain point in the program. Note that we want to analyze the method lazily - * and therefore use the analyzedMethod variable - */ - private def getTypesAtInstruction(bblock: BasicBlock, index: Int): List[TypeKind] = { - // get the stack at the block entry - var typeInfo = getTypesAtBlockEntry(bblock) - - // perform tfa to the current instruction - log(" stack at the beginning of block " + bblock + " in function " + - bblock.method + ": " + typeInfo.stack) - for (i <- 0 to (index - 1)) { - typeInfo = tfa.interpret(typeInfo, bblock(i)) - log(" stack after interpret: " + typeInfo.stack + " after instruction " + - bblock(i)) - } - log(" stack before instruction " + index + " of block " + bblock + " in function " + - bblock.method + ": " + typeInfo.stack) - - // return the result - typeInfo.stack.types - } - - /** - * Gets the stack at the block entry. Normally the typeFlowAnalysis should be run again, but we know how to compute - * the stack for handler duplicates. For the locals, it's safe to assume the info from the original handler is - * still valid (a more precise analysis can be done, but it's not necessary) - */ - private def getTypesAtBlockEntry(bblock: BasicBlock): tfa.lattice.Elem = { - // lazily perform tfa, because it's expensive - // cache results by block label, as rewriting the code messes up the block's hashCode - if (analyzedMethod eq NoIMethod) { - analyzedMethod = bblock.method - tfa.init(bblock.method) - tfa.run() - log(" performed tfa on method: " + bblock.method) - - for (block <- bblock.method.blocks.sortBy(_.label)) - tfaCache += block.label -> tfa.in(block) - } - - log(" getting typeinfo at the beginning of block " + bblock) - - tfaCache.getOrElse(bblock.label, { - // this block was not analyzed, but it's a copy of some other block so its stack should be the same - log(" getting typeinfo at the beginning of block " + bblock + " as a copy of " + - handlerCopiesInverted(bblock)) - val (origBlock, exception) = handlerCopiesInverted(bblock) - val typeInfo = getTypesAtBlockEntry(origBlock) - val stack = - if (handlerLocal(origBlock).nonEmpty) Nil // empty stack, the handler copy expects an empty stack - else List(exception) // one slot on the stack for the exception - - // If we use the mutability property, it crashes the analysis - tfa.lattice.IState(new analysis.VarBinding(typeInfo.vars), new icodes.TypeStack(stack)) - }) - } - - /** - * Finds the first exception handler that matches the current exception - * - * Note the following code: - * {{{ - * try { - * throw new IllegalArgumentException("...") - * } catch { - * case e: RuntimeException => log("RuntimeException") - * case i: IllegalArgumentException => log("IllegalArgumentException") - * } - * }}} - * - * will print "RuntimeException" => we need the *first* valid handler - * - * There's a hidden catch here: say we have the following code: - * {{{ - * try { - * val exception: Throwable = - * if (scala.util.Random.nextInt % 2 == 0) - * new IllegalArgumentException("even") - * else - * new StackOverflowError("odd") - * throw exception - * } catch { - * case e: IllegalArgumentException => - * println("Correct, IllegalArgumentException") - * case e: StackOverflowError => - * println("Correct, StackOverflowException") - * case t: Throwable => - * println("WROOOONG, not Throwable!") - * } - * }}} - * - * We don't want to select a handler if there's at least one that's more specific! - */ - def findExceptionHandler(thrownException: TypeKind, handlers: List[BasicBlock]): Option[(BasicBlock, TypeKind)] = { - for (handler <- handlers ; LOAD_EXCEPTION(clazz) <- handler take 1) { - val caughtException = toTypeKind(clazz.tpe) - // we'll do inlining here: createdException <:< thrownException <:< caughtException, good! - if (thrownException <:< caughtException) - return Some((handler, caughtException)) - // we can't do inlining here, the handling mechanism is more precise than we can reason about - if (caughtException <:< thrownException) - return None - // no result yet, look deeper in the handler stack - } - None - } - - /** - * This function takes care of duplicating the basic block code for inlining the handler - * - * Note: This function does not duplicate the same basic block twice. It will contain a map of the duplicated - * basic blocks - */ - private def duplicateExceptionHandlerCache(handler: BasicBlock) = - handlerCopies.getOrElseUpdate(handler, duplicateExceptionHandler(handler)) - - /** This function takes care of actual duplication */ - private def duplicateExceptionHandler(handler: BasicBlock): Option[(Option[Local], BasicBlock)] = { - log(" duplicating handler block " + handler) - - handler take 2 match { - case Seq(LOAD_EXCEPTION(caughtClass), next) => - val (dropCount, exceptionLocal) = next match { - case STORE_LOCAL(local) => (2, Some(local)) // we drop both LOAD_EXCEPTION and STORE_LOCAL - case _ => (1, None) // we only drop the LOAD_EXCEPTION and expect the exception on the stack - } - val caughtException = toTypeKind(caughtClass.tpe) - // copy the exception handler code once again, dropping the LOAD_EXCEPTION - val copy = handler.code.newBlock() - copy.emitOnly((handler.iterator drop dropCount).toSeq: _*) - - // extend the handlers of the handler to the copy - for (parentHandler <- handler.method.exh ; if parentHandler covers handler) { - parentHandler.addCoveredBlock(copy) - // notify the parent handler that the successors changed - parentHandler.startBlock.touched = true - } - - // notify the successors of the inlined handler might have changed - copy.touched = true - handler.touched = true - log(" duplicated handler block " + handler + " to " + copy) - - // announce the duplicate handler - handlerCopiesInverted(copy) = ((handler, caughtException)) - todoBlocks ::= copy - - Some((exceptionLocal, copy)) - - case _ => - reporter.warning(NoPosition, "Unable to inline the exception handler due to incorrect format:\n" + - handler.iterator.mkString("\n")) - None - } - } - } -} diff --git a/src/compiler/scala/tools/nsc/backend/opt/Inliners.scala b/src/compiler/scala/tools/nsc/backend/opt/Inliners.scala deleted file mode 100644 index 8cd2a14066..0000000000 --- a/src/compiler/scala/tools/nsc/backend/opt/Inliners.scala +++ /dev/null @@ -1,1075 +0,0 @@ -/* NSC -- new Scala compiler - * Copyright 2005-2013 LAMP/EPFL - * @author Iulian Dragos - */ - - -package scala.tools.nsc -package backend.opt - -import scala.collection.mutable -import scala.tools.nsc.symtab._ -import scala.reflect.internal.util.NoSourceFile - -/** - * Inliner balances two competing goals: - * (a) aggressive inlining of: - * (a.1) the apply methods of anonymous closures, so that their anon-classes can be eliminated; - * (a.2) higher-order-methods defined in an external library, e.g. `Range.foreach()` among many others. - * (b) circumventing the barrier to inter-library inlining that private accesses in the callee impose. - * - * Summing up the discussion in SI-5442 and SI-5891, - * the current implementation achieves to a large degree both goals above, and - * overcomes a problem exhibited by previous versions: - * - * (1) Problem: Attempting to access a private member `p` at runtime resulting in an `IllegalAccessError`, - * where `p` is defined in a library L, and is accessed from a library C (for Client), - * where C was compiled against L', an optimized version of L where the inliner made `p` public at the bytecode level. - * The only such members are fields, either synthetic or isParamAccessor, and thus having a dollar sign in their name - * (the accessibility of methods and constructors isn't touched by the inliner). - * - * Thus we add one more goal to our list: - * (c) Compile C (either optimized or not) against any of L or L', - * so that it runs with either L or L' (in particular, compile against L' and run with L). - * - * The chosen strategy is described in some detail in the comments for `accessRequirements()` and `potentiallyPublicized()`. - * Documentation at http://lamp.epfl.ch/~magarcia/ScalaCompilerCornerReloaded/2011Q4/Inliner.pdf - * - * @author Iulian Dragos - */ -abstract class Inliners extends SubComponent { - import global._ - import icodes._ - import icodes.opcodes._ - import definitions.{ - NullClass, NothingClass, ObjectClass, - PredefModule, RuntimePackage, ScalaInlineClass, ScalaNoInlineClass, - isFunctionType, isByNameParamType - } - - val phaseName = "inliner" - - override val enabled: Boolean = settings.inline - - /** Debug - for timing the inliner. */ - /**** - private def timed[T](s: String, body: => T): T = { - val t1 = System.currentTimeMillis() - val res = body - val t2 = System.currentTimeMillis() - val ms = (t2 - t1).toInt - if (ms >= MAX_INLINE_MILLIS) - println("%s: %d milliseconds".format(s, ms)) - - res - } - ****/ - - /** Look up implementation of method 'sym in 'clazz'. - */ - def lookupImplFor(sym: Symbol, clazz: Symbol): Symbol = { - // TODO: verify that clazz.superClass is equivalent here to clazz.tpe.parents(0).typeSymbol (.tpe vs .info) - def needsLookup = ( - (clazz != NoSymbol) - && (clazz != sym.owner) - && !sym.isEffectivelyFinalOrNotOverridden - && clazz.isEffectivelyFinalOrNotOverridden - ) - def lookup(clazz: Symbol): Symbol = { - // println("\t\tlooking up " + meth + " in " + clazz.fullName + " meth.owner = " + meth.owner) - assert(clazz != NoSymbol, "Walked up past Object.superClass looking for " + sym + - ", most likely this reveals the TFA at fault (receiver and callee don't match).") - if (sym.owner == clazz || isBottomType(clazz)) sym - else sym.overridingSymbol(clazz) orElse ( - if (sym.owner.isTrait) sym - else lookup(clazz.superClass) - ) - } - if (needsLookup) { - val concreteMethod = lookup(clazz) - debuglog("\tlooked up method: " + concreteMethod.fullName) - - concreteMethod - } - else sym - } - - /* A warning threshold */ - private final val MAX_INLINE_MILLIS = 2000 - - /** The maximum size in basic blocks of methods considered for inlining. */ - final val MAX_INLINE_SIZE = 16 - - /** Maximum loop iterations. */ - final val MAX_INLINE_RETRY = 15 - - /** Small method size (in blocks) */ - val SMALL_METHOD_SIZE = 1 - - /** Create a new phase */ - override def newPhase(p: Phase) = new InliningPhase(p) - - /** The Inlining phase. - */ - class InliningPhase(prev: Phase) extends ICodePhase(prev) { - def name = phaseName - val inliner = new Inliner - - object iclassOrdering extends Ordering[IClass] { - def compare(a: IClass, b: IClass) = { - val sourceNamesComparison = (a.cunit.toString() compare b.cunit.toString()) - if(sourceNamesComparison != 0) sourceNamesComparison - else { - val namesComparison = (a.toString() compare b.toString()) - if(namesComparison != 0) namesComparison - else { - a.symbol.id compare b.symbol.id - } - } - } - } - val queue = new mutable.PriorityQueue[IClass]()(iclassOrdering) - - override def apply(c: IClass) { queue += c } - - override def run() { - knownLacksInline.clear() - knownHasInline.clear() - try { - super.run() - for(c <- queue) { inliner analyzeClass c } - } finally { - inliner.clearCaches() - knownLacksInline.clear() - knownHasInline.clear() - } - } - } - - def isBottomType(sym: Symbol) = sym == NullClass || sym == NothingClass - - /** Is the given class a closure? */ - def isClosureClass(cls: Symbol): Boolean = - cls.isFinal && cls.isSynthetic && !cls.isModuleClass && cls.isAnonymousFunction - - /* - TODO now that Inliner runs faster we could consider additional "monadic methods" (in the limit, all those taking a closure as last arg) - Any "monadic method" occurring in a given caller C that is not `isMonadicMethod()` will prevent CloseElim from eliminating - any anonymous-closure-class any whose instances are given as argument to C invocations. - */ - def isMonadicMethod(sym: Symbol) = { - nme.unspecializedName(sym.name) match { - case nme.foreach | nme.filter | nme.withFilter | nme.map | nme.flatMap => true - case _ => false - } - } - - val knownLacksInline = mutable.Set.empty[Symbol] // cache to avoid multiple inliner.hasInline() calls. - val knownHasInline = mutable.Set.empty[Symbol] // as above. Motivated by the need to warn on "inliner failures". - - def hasInline(sym: Symbol) = { - if (knownLacksInline(sym)) false - else if(knownHasInline(sym)) true - else { - val b = (sym hasAnnotation ScalaInlineClass) - if(b) { knownHasInline += sym } - else { knownLacksInline += sym } - - b - } - } - - def hasNoInline(sym: Symbol) = sym hasAnnotation ScalaNoInlineClass - - /** - * Simple inliner. - */ - class Inliner { - object NonPublicRefs extends Enumeration { - val Private, Protected, Public = Value - - /** Cache whether a method calls private members. */ - val usesNonPublics = mutable.Map.empty[IMethod, Value] - } - import NonPublicRefs._ - - /** The current iclass */ - private var currentIClazz: IClass = _ - private def warn(pos: Position, msg: String) = currentRun.reporting.inlinerWarning(pos, msg) - - private def ownedName(sym: Symbol): String = exitingUncurry { - val count = ( - if (!sym.isMethod) 1 - else if (sym.owner.isAnonymousFunction) 3 - else 2 - ) - (sym.ownerChain take count filterNot (_.isPackageClass)).reverseMap(_.nameString).mkString(".") - } - private def inlineLog(what: String, main: => String, comment: => String) { - def cstr = comment match { - case "" => "" - case str => " // " + str - } - val width = if (currentIClazz eq null) 40 else currentIClazz.symbol.enclosingPackage.fullName.length + 25 - val fmt = "%8s %-" + width + "s" + cstr - log(fmt.format(what, main)) - } - private def inlineLog(what: String, main: Symbol, comment: => String) { - inlineLog(what, ownedName(main), comment) - } - - val recentTFAs = mutable.Map.empty[Symbol, Tuple2[Boolean, analysis.MethodTFA]] - - private def getRecentTFA(incm: IMethod, forceable: Boolean): (Boolean, analysis.MethodTFA) = { - - def containsRETURN(blocks: List[BasicBlock]) = blocks exists { bb => bb.lastInstruction.isInstanceOf[RETURN] } - - val opt = recentTFAs.get(incm.symbol) - if(opt.isDefined) { - // FYI val cachedBBs = opt.get._2.in.keySet - // FYI assert(incm.blocks.toSet == cachedBBs) - // incm.code.touched plays no role here - return opt.get - } - - val hasRETURN = containsRETURN(incm.code.blocksList) || (incm.exh exists { eh => containsRETURN(eh.blocks) }) - var a: analysis.MethodTFA = null - if(hasRETURN) { a = new analysis.MethodTFA(incm); a.run() } - - if(forceable) { recentTFAs.put(incm.symbol, (hasRETURN, a)) } - - (hasRETURN, a) - } - - def clearCaches() { - // methods - NonPublicRefs.usesNonPublics.clear() - recentTFAs.clear() - tfa.knownUnsafe.clear() - tfa.knownSafe.clear() - tfa.knownNever.clear() - // basic blocks - tfa.preCandidates.clear() - tfa.relevantBBs.clear() - // callsites - tfa.remainingCALLs.clear() - tfa.isOnWatchlist.clear() - } - - object imethodOrdering extends Ordering[IMethod] { - def compare(a: IMethod, b: IMethod) = { - val namesComparison = (a.toString() compare b.toString()) - if(namesComparison != 0) namesComparison - else { - a.symbol.id compare b.symbol.id - } - } - } - - def analyzeClass(cls: IClass): Unit = - if (settings.inline) { - inlineLog("class", s"${cls.symbol.decodedName}", s"analyzing ${cls.methods.size} methods in $cls") - - this.currentIClazz = cls - val ms = cls.methods sorted imethodOrdering - ms foreach { im => - if (hasInline(im.symbol)) { - inlineLog("skip", im.symbol, "no inlining into @inline methods") - } - else if(im.hasCode && !im.symbol.isBridge) { - analyzeMethod(im) - } - } - } - - val tfa = new analysis.MTFAGrowable() - tfa.stat = global.settings.YstatisticsEnabled - val staleOut = new mutable.ListBuffer[BasicBlock] - val splicedBlocks = mutable.Set.empty[BasicBlock] - val staleIn = mutable.Set.empty[BasicBlock] - - /** - * A transformation local to the body of the IMethod received as argument. - * An inlining decision consists in replacing a callsite with the body of the callee. - * Please notice that, because `analyzeMethod()` itself may modify a method body, - * the particular callee bodies that end up being inlined depend on the particular order in which methods are visited - * (no topological sorting over the call-graph is attempted). - * - * Making an inlining decision requires type-flow information for both caller and callee. - * Regarding the caller, such information is needed only for basic blocks containing inlining candidates - * (and their transitive predecessors). This observation leads to using a custom type-flow analysis (MTFAGrowable) - * that can be re-inited, i.e. that reuses lattice elements (type-flow information computed in a previous iteration) - * as starting point for faster convergence in a new iteration. - * - * The mechanics of inlining are iterative for a given invocation of `analyzeMethod(m)`, - * and are affected by inlinings from previous iterations - * (ie, "heuristic" rules are based on statistics tracked for that purpose): - * - * (1) before the iterations proper start, so-called preinlining is performed. - * Those callsites whose (receiver, concreteMethod) are both known statically - * can be analyzed for inlining before computing a type-flow. Details in `preInline()` - * - * (2) the first iteration computes type-flow information for basic blocks containing inlining candidates - * (and their transitive predecessors), so called `relevantBBs` basic blocks. - * The ensuing analysis of each candidate (performed by `analyzeInc()`) - * may result in a CFG isomorphic to that of the callee being inserted in place of the callsite - * (i.e. a CALL_METHOD instruction is replaced with a single-entry single-exit CFG, - * a substitution we call "successful inlining"). - * - * (3) following iterations have `relevantBBs` updated to focus on the inlined basic blocks and their successors only. - * Details in `MTFAGrowable.reinit()` - * */ - def analyzeMethod(m: IMethod): Unit = { - // m.normalize - if (settings.debug) - inlineLog("caller", ownedName(m.symbol), "in " + m.symbol.owner.fullName) - - val sizeBeforeInlining = m.code.blockCount - val instrBeforeInlining = m.code.instructionCount - var retry = false - var count = 0 - - // fresh name counter - val fresh = mutable.HashMap.empty[String, Int] withDefaultValue 0 - // how many times have we already inlined this method here? - val inlinedMethodCount = mutable.HashMap.empty[Symbol, Int] withDefaultValue 0 - val caller = new IMethodInfo(m) - def analyzeMessage = s"Analyzing ${caller.length} blocks of $m for inlining sites." - - def preInline(isFirstRound: Boolean): Int = { - val inputBlocks = caller.m.linearizedBlocks() - val callsites: Function1[BasicBlock, List[opcodes.CALL_METHOD]] = { - if(isFirstRound) tfa.conclusives else tfa.knownBeforehand - } - inlineWithoutTFA(inputBlocks, callsites) - } - - /* - * Inline straightforward callsites (those that can be inlined without a TFA). - * - * To perform inlining, all we need to know is listed as formal params in `analyzeInc()`: - * - callsite and block containing it - * - actual (ie runtime) class of the receiver - * - actual (ie runtime) method being invoked - * - stack length just before the callsite (to check whether enough arguments have been pushed). - * The assert below lists the conditions under which "no TFA is needed" - * (the statically known receiver and method are both final, thus, at runtime they can't be any others than those). - * - */ - def inlineWithoutTFA(inputBlocks: Traversable[BasicBlock], callsites: Function1[BasicBlock, List[opcodes.CALL_METHOD]]): Int = { - var inlineCount = 0 - import scala.util.control.Breaks._ - for(x <- inputBlocks; easyCake = callsites(x); if easyCake.nonEmpty) { - breakable { - for(ocm <- easyCake) { - assert(ocm.method.isEffectivelyFinalOrNotOverridden && ocm.method.owner.isEffectivelyFinalOrNotOverridden) - if(analyzeInc(ocm, x, ocm.method.owner, -1, ocm.method)) { - inlineCount += 1 - break() - } - } - } - } - - inlineCount - } - - /* - * Decides whether it's feasible and desirable to inline the body of the method given by `concreteMethod` - * at the program point given by `i` (a callsite). The boolean result indicates whether inlining was performed. - * - */ - def analyzeInc(i: CALL_METHOD, bb: BasicBlock, receiver: Symbol, stackLength: Int, concreteMethod: Symbol): Boolean = { - assert(bb.toList contains i, "Candidate callsite does not belong to BasicBlock.") - val shouldWarn = hasInline(i.method) - - def warnNoInline(reason: String): Boolean = { - def msg = "Could not inline required method %s because %s.".format(i.method.unexpandedName.decode, reason) - if (settings.debug) - inlineLog("fail", i.method.fullName, reason) - if (shouldWarn) - warn(i.pos, msg) - - false - } - - var isAvailable = icodes available concreteMethod.enclClass - - if (!isAvailable && shouldLoadImplFor(concreteMethod, receiver)) { - // Until r22824 this line was: - // icodes.icode(concreteMethod.enclClass, true) - // - // Changing it to - // icodes.load(concreteMethod.enclClass) - // was the proximate cause for SI-3882: - // error: Illegal index: 0 overlaps List((variable par1,LONG)) - // error: Illegal index: 0 overlaps List((variable par1,LONG)) - isAvailable = icodes.load(concreteMethod.enclClass) - } - - def isCandidate = ( - isClosureClass(receiver) - || concreteMethod.isEffectivelyFinalOrNotOverridden - || receiver.isEffectivelyFinalOrNotOverridden - ) - - def isApply = concreteMethod.name == nme.apply - - def isCountable = !( - isClosureClass(receiver) - || isApply - || isMonadicMethod(concreteMethod) - || receiver.enclosingPackage == definitions.RuntimePackage - ) // only count non-closures - - debuglog("Treating " + i - + "\n\treceiver: " + receiver - + "\n\ticodes.available: " + isAvailable - + "\n\tconcreteMethod.isEffectivelyFinalOrNotOverridden: " + concreteMethod.isEffectivelyFinalOrNotOverridden) - - if (!isCandidate) warnNoInline("it can be overridden") - else if (!isAvailable) warnNoInline("bytecode unavailable") - else lookupIMethod(concreteMethod, receiver) filter (callee => callee.hasCode || warnNoInline("callee has no code")) exists { callee => - val inc = new IMethodInfo(callee) - val pair = new CallerCalleeInfo(caller, inc, fresh, inlinedMethodCount) - - if (inc.hasHandlers && (stackLength == -1)) { - // no inlining is done, yet don't warn about it, stackLength == -1 indicates we're trying to inlineWithoutTFA. - // Shortly, a TFA will be computed and an error message reported if indeed inlining not possible. - false - } - else { - val isSafe = pair isStampedForInlining stackLength match { - case DontInlineHere(msg) => warnNoInline(msg) - case NeverSafeToInline => false - case InlineableAtThisCaller => true - case FeasibleInline(required, toPublicize) => - for (f <- toPublicize) { - inlineLog("access", f, "making public") - f setFlag Flags.notPRIVATE - f setFlag Flags.notPROTECTED - } - // only add to `knownSafe` after all `toPublicize` fields actually made public. - if (required == NonPublicRefs.Public) - tfa.knownSafe += inc.sym - - true - } - isSafe && { - retry = true - if (isCountable) count += 1 - pair.doInline(bb, i) - if (!pair.isInlineForced || inc.isMonadic) caller.inlinedCalls += 1 - inlinedMethodCount(inc.sym) += 1 - - // Remove the caller from the cache (this inlining might have changed its calls-private relation). - usesNonPublics -= m - recentTFAs -= m.symbol - true - } - } - } - } - - /* Pre-inlining consists in invoking the usual inlining subroutine with (receiver class, concrete method) pairs as input - * where both method and receiver are final, which implies that the receiver computed via TFA will always match `concreteMethod.owner`. - * - * As with any invocation of `analyzeInc()` the inlining outcome is based on heuristics which favor inlining an isMonadicMethod before other methods. - * That's why preInline() is invoked twice: any inlinings downplayed by the heuristics during the first round get an opportunity to rank higher during the second. - * - * As a whole, both `preInline()` invocations amount to priming the inlining process, - * so that the first TFA that is run afterwards is able to gain more information as compared to a cold-start. - */ - /*val totalPreInlines = */ { // Val name commented out to emphasize it is never used - val firstRound = preInline(isFirstRound = true) - if(firstRound == 0) 0 else (firstRound + preInline(isFirstRound = false)) - } - staleOut.clear() - splicedBlocks.clear() - staleIn.clear() - - do { - retry = false - debuglog(analyzeMessage) - - /* it's important not to inline in unreachable basic blocks. linearizedBlocks() returns only reachable ones. */ - tfa.callerLin = caller.m.linearizedBlocks() - /* TODO Do we really want to inline inside exception handlers? - * Seems counterproductive (the larger the method the less likely it will be JITed). - * The alternative would be `linearizer.linearizeAt(caller.m, caller.m.startBlock)`. - * And, we would cut down on TFA iterations, too. - * See also comment on the same topic in TypeFlowAnalysis. */ - - tfa.reinit(m, staleOut.toList, splicedBlocks, staleIn) - tfa.run - - staleOut.clear() - splicedBlocks.clear() - staleIn.clear() - - import scala.util.control.Breaks._ - for(bb <- tfa.callerLin; if tfa.preCandidates(bb)) { - val cms = bb.toList collect { case cm : CALL_METHOD => cm } - breakable { - for (cm <- cms; if tfa.remainingCALLs.isDefinedAt(cm)) { - val analysis.CallsiteInfo(_, receiver, stackLength, concreteMethod) = tfa.remainingCALLs(cm) - if (analyzeInc(cm, bb, receiver, stackLength, concreteMethod)) { - break() - } - } - } - } - - /* As part of inlining, some instructions are moved to a new block. - * In detail: the instructions moved to a new block originally appeared after a (by now inlined) callsite. - * Their new home is an `afterBlock` created by `doInline()` to that effect. - * Each block in staleIn is one such `afterBlock`. - * - * Some of those instructions may be CALL_METHOD possibly tracked in `remainingCALLs` - * (with an entry still noting the old containing block). However, that causes no problem: - * - * (1) such callsites won't be analyzed for inlining by `analyzeInc()` (*in this iteration*) - * because of the `break` that abandons the original basic block where it was contained. - * - * (2) Additionally, its new containing block won't be visited either (*in this iteration*) - * because the new blocks don't show up in the linearization computed before inlinings started: - * `for(bb <- tfa.callerLin; if tfa.preCandidates(bb)) {` - * - * For a next iteration, the new home of any instructions that have moved - * will be tracked properly in `remainingCALLs` after `MTFAGrowable.reinit()` puts on radar their new homes. - * - */ - if(retry) { - for(afterBlock <- staleIn) { - val justCALLsAfter = afterBlock.toList collect { case c : opcodes.CALL_METHOD => c } - for(ia <- justCALLsAfter) { tfa.remainingCALLs.remove(ia) } - } - } - - /* - if(splicedBlocks.nonEmpty) { // TODO explore (saves time but leads to slightly different inlining decisions) - // opportunistically perform straightforward inlinings before the next typeflow round - val savedRetry = retry - val savedStaleOut = staleOut.toSet; staleOut.clear() - val savedStaleIn = staleIn.toSet ; staleIn.clear() - val howmany = inlineWithoutTFA(splicedBlocks, tfa.knownBeforehand) - splicedBlocks ++= staleIn - staleOut.clear(); staleOut ++= savedStaleOut; - staleIn.clear(); staleIn ++= savedStaleIn; - retry = savedRetry - } - */ - - if (tfa.stat) - log(m.symbol.fullName + " iterations: " + tfa.iterations + " (size: " + caller.length + ")") - } - while (retry && count < MAX_INLINE_RETRY) - - for(inlFail <- tfa.warnIfInlineFails) { - warn(inlFail.pos, "At the end of the day, could not inline @inline-marked method " + inlFail.method.unexpandedName.decode) - } - - m.normalize() - if (sizeBeforeInlining > 0) { - val instrAfterInlining = m.code.instructionCount - val inlinings = caller.inlinedCalls - if (inlinings > 0) { - val s1 = s"instructions $instrBeforeInlining -> $instrAfterInlining" - val s2 = if (sizeBeforeInlining == m.code.blockCount) "" else s", blocks $sizeBeforeInlining -> ${m.code.blockCount}" - val callees = inlinedMethodCount.toList map { case (k, v) => k.fullNameString + ( if (v == 1) "" else "/" + v ) } - - inlineLog("inlined", m.symbol.fullName, callees.sorted.mkString(inlinings + " inlined: ", ", ", "")) - inlineLog("<<tldr>>", m.symbol.fullName, s"${m.symbol.nameString}: $s1$s2") - } - } - } - - private def isHigherOrderMethod(sym: Symbol) = ( - sym.isMethod - && enteringExplicitOuter(sym.info.paramTypes exists isFunctionType) // was "at erasurePhase.prev" - ) - - /** Should method 'sym' being called in 'receiver' be loaded from disk? */ - def shouldLoadImplFor(sym: Symbol, receiver: Symbol): Boolean = { - def alwaysLoad = (receiver.enclosingPackage == RuntimePackage) || (receiver == PredefModule.moduleClass) - def loadCondition = sym.isEffectivelyFinalOrNotOverridden && isMonadicMethod(sym) && isHigherOrderMethod(sym) - - val res = hasInline(sym) || alwaysLoad || loadCondition - debuglog("shouldLoadImplFor: " + receiver + "." + sym + ": " + res) - res - } - - class IMethodInfo(val m: IMethod) { - override def toString = m.toString - - val sym = m.symbol - def owner = sym.owner - def paramTypes = sym.info.paramTypes - def minimumStack = paramTypes.length + 1 - - def isBridge = sym.isBridge - val isInClosure = isClosureClass(owner) - val isHigherOrder = isHigherOrderMethod(sym) - def isMonadic = isMonadicMethod(sym) - - def handlers = m.exh - def blocks = m.blocks - def locals = m.locals - def length = blocks.length - def openBlocks = blocks filterNot (_.closed) - def instructions = m.code.instructions - - def isSmall = (length <= SMALL_METHOD_SIZE) && blocks(0).length < 10 - def isLarge = length > MAX_INLINE_SIZE - def isRecursive = m.recursive - def hasHandlers = handlers.nonEmpty || m.bytecodeHasEHs - - def isSynchronized = sym.hasFlag(Flags.SYNCHRONIZED) - def hasNonFinalizerHandler = handlers exists { - case _: Finalizer => true - case _ => false - } - - // the number of inlined calls in 'm', used by 'isScoreOK' - var inlinedCalls = 0 - - def addLocals(ls: List[Local]) = m.locals ++= ls - def addLocal(l: Local) = addLocals(List(l)) - def addHandlers(exhs: List[ExceptionHandler]) = m.exh = exhs ::: m.exh - - /** - * This method inspects the callee's instructions, finding out the most restrictive accessibility implied by them. - * - * Rather than giving up upon encountering an access to a private field `p`, it provisorily admits `p` as "can-be-made-public", provided: - * - `p` is being compiled as part of this compilation run, and - * - `p` is synthetic or param-accessor. - * - * This method is side-effect free, in particular it lets the invoker decide - * whether the accessibility of the `toBecomePublic` fields should be changed or not. - */ - def accessRequirements: AccessReq = { - - var toBecomePublic: List[Symbol] = Nil - - def check(sym: Symbol, cond: Boolean) = - if (cond) Private - else if (sym.isProtected) Protected - else Public - - def canMakePublic(f: Symbol): Boolean = - (m.sourceFile ne NoSourceFile) && - (f.isSynthetic || f.isParamAccessor) && - { toBecomePublic = f :: toBecomePublic; true } - - /* A safety check to consider as private, for the purposes of inlining, a public field that: - * (1) is defined in an external library, and - * (2) can be presumed synthetic (due to a dollar sign in its name). - * Such field was made public by `doMakePublic()` and we don't want to rely on that, - * because under other compilation conditions (ie no -optimize) that won't be the case anymore. - * - * This allows aggressive intra-library inlining (making public if needed) - * that does not break inter-library scenarios (see comment for `Inliners`). - * - * TODO handle more robustly the case of a trait var changed at the source-level from public to private[this] - * (eg by having ICodeReader use unpickler, see SI-5442). - - DISABLED - - def potentiallyPublicized(f: Symbol): Boolean = { - (m.sourceFile eq NoSourceFile) && f.name.containsChar('$') - } - */ - - - def isPrivateForInlining(sym: Symbol): Boolean = { - if (sym.isJavaDefined) { - def check(sym: Symbol) = !(sym.isPublic || sym.isProtected) - check(sym) || check(sym.owner) // SI-7582 Must check the enclosing class *and* the symbol for Java. - } - else sym.isPrivate // Scala never emits package-private bytecode - } - - def checkField(f: Symbol) = check(f, isPrivateForInlining(f) && !canMakePublic(f)) - def checkSuper(n: Symbol) = check(n, isPrivateForInlining(n) || !n.isClassConstructor) - def checkMethod(n: Symbol) = check(n, isPrivateForInlining(n)) - - def getAccess(i: Instruction) = i match { - case CALL_METHOD(n, SuperCall(_)) => checkSuper(n) - case CALL_METHOD(n, _) => checkMethod(n) - case LOAD_FIELD(f, _) => checkField(f) - case STORE_FIELD(f, _) => checkField(f) - case _ => Public - } - - var seen = Public - val iter = instructions.iterator - while((seen ne Private) && iter.hasNext) { - val i = iter.next() - getAccess(i) match { - case Private => - inlineLog("access", s"instruction $i requires private access", "pos=" + i.pos) - toBecomePublic = Nil - seen = Private - case Protected => seen = Protected - case _ => () - } - } - - AccessReq(seen, toBecomePublic) - } - - } - - /** - * Classifies a pair (caller, callee) into one of four categories: - * - * (a) inlining should be performed, classified in turn into: - * (a.1) `InlineableAtThisCaller`: unconditionally at this caller - * (a.2) `FeasibleInline`: it only remains for certain access requirements to be met (see `IMethodInfo.accessRequirements()`) - * - * (b) inlining shouldn't be performed, classified in turn into: - * (b.1) `DontInlineHere`: indicates that this particular occurrence of the callee at the caller shouldn't be inlined. - * - Nothing is said about the outcome for other callers, or for other occurrences of the callee for the same caller. - * - In particular inlining might be possible, but heuristics gave a low score for it. - * (b.2) `NeverSafeToInline`: the callee can't be inlined anywhere, irrespective of caller. - * - * The classification above is computed by `isStampedForInlining()` based on which `analyzeInc()` goes on to: - * - either log the reason for failure --- case (b) ---, - * - or perform inlining --- case (a) ---. - */ - sealed abstract class InlineSafetyInfo - case object NeverSafeToInline extends InlineSafetyInfo - case object InlineableAtThisCaller extends InlineSafetyInfo - case class DontInlineHere(msg: String) extends InlineSafetyInfo - case class FeasibleInline(accessNeeded: NonPublicRefs.Value, toBecomePublic: List[Symbol]) extends InlineSafetyInfo - - case class AccessReq( - accessNeeded: NonPublicRefs.Value, - toBecomePublic: List[Symbol] - ) - - final class CallerCalleeInfo(val caller: IMethodInfo, val inc: IMethodInfo, fresh: mutable.Map[String, Int], inlinedMethodCount: scala.collection.Map[Symbol, Int]) { - - assert(!caller.isBridge && inc.m.hasCode, - "A guard in Inliner.analyzeClass() should have prevented from getting here.") - - def isLargeSum = caller.length + inc.length - 1 > SMALL_METHOD_SIZE - - private def freshName(s: String): TermName = { - fresh(s) += 1 - newTermName(s + fresh(s)) - } - - private def isKnownToInlineSafely: Boolean = { tfa.knownSafe(inc.sym) } - - val isInlineForced = hasInline(inc.sym) - val isInlineForbidden = hasNoInline(inc.sym) - assert(!(isInlineForced && isInlineForbidden), "method ("+inc.m+") marked both @inline and @noinline.") - - /** Inline 'inc' into 'caller' at the given block and instruction. - * The instruction must be a CALL_METHOD. - */ - def doInline(block: BasicBlock, instr: CALL_METHOD) { - - staleOut += block - - tfa.remainingCALLs.remove(instr) // this bookkeeping is done here and not in MTFAGrowable.reinit due to (1st) convenience and (2nd) necessity. - tfa.isOnWatchlist.remove(instr) // ditto - tfa.warnIfInlineFails.remove(instr) - - val targetPos = instr.pos - - def blockEmit(i: Instruction) = block.emit(i, targetPos) - def newLocal(baseName: String, kind: TypeKind) = - new Local(caller.sym.newVariable(freshName(baseName), targetPos) setInfo kind.toType, kind, false) - - val (hasRETURN, a) = getRecentTFA(inc.m, isInlineForced) - - /* The exception handlers that are active at the current block. */ - val activeHandlers = caller.handlers filter (_ covered block) - - /* Map 'original' blocks to the ones inlined in the caller. */ - val inlinedBlock = mutable.Map[BasicBlock, BasicBlock]() - - val varsInScope = mutable.HashSet[Local]() ++= block.varsInScope - - /* Side effects varsInScope when it sees SCOPE_ENTERs. */ - def instrBeforeFilter(i: Instruction): Boolean = { - i match { case SCOPE_ENTER(l) => varsInScope += l ; case _ => () } - i ne instr - } - val instrBefore = block.toList takeWhile instrBeforeFilter - val instrAfter = block.toList drop (instrBefore.length + 1) - - assert(!instrAfter.isEmpty, "CALL_METHOD cannot be the last instruction in block!") - - // store the '$this' into the special local - val inlinedThis = newLocal("$inlThis", REFERENCE(ObjectClass)) - - /* buffer for the returned value */ - val retVal = inc.m.returnType match { - case UNIT => null - case x => newLocal("$retVal", x) - } - - val inlinedLocals = mutable.HashMap.empty[Local, Local] - - /* Add a new block in the current context. */ - def newBlock() = { - val b = caller.m.code.newBlock() - activeHandlers foreach (_ addCoveredBlock b) - if (retVal ne null) b.varsInScope += retVal - b.varsInScope += inlinedThis - b.varsInScope ++= varsInScope - b - } - - def translateExh(e: ExceptionHandler) = { - val handler: ExceptionHandler = e.dup - handler.covered = handler.covered map inlinedBlock - handler setStartBlock inlinedBlock(e.startBlock) - handler - } - - /* alfa-rename `l` in caller's context. */ - def dupLocal(l: Local): Local = { - val sym = caller.sym.newVariable(freshName(l.sym.name.toString), l.sym.pos) - // sym.setInfo(l.sym.tpe) - val dupped = new Local(sym, l.kind, false) - inlinedLocals(l) = dupped - dupped - } - - val afterBlock = newBlock() - - /* Map from nw.init instructions to their matching NEW call */ - val pending: mutable.Map[Instruction, NEW] = new mutable.HashMap - - /* Map an instruction from the callee to one suitable for the caller. */ - def map(i: Instruction): Instruction = { - def assertLocal(l: Local) = { - assert(caller.locals contains l, "Could not find local '" + l + "' in locals, nor in inlinedLocals: " + inlinedLocals) - i - } - def isInlined(l: Local) = inlinedLocals isDefinedAt l - - val newInstr = i match { - case THIS(clasz) => LOAD_LOCAL(inlinedThis) - case STORE_THIS(_) => STORE_LOCAL(inlinedThis) - case JUMP(whereto) => JUMP(inlinedBlock(whereto)) - case CJUMP(succ, fail, cond, kind) => CJUMP(inlinedBlock(succ), inlinedBlock(fail), cond, kind) - case CZJUMP(succ, fail, cond, kind) => CZJUMP(inlinedBlock(succ), inlinedBlock(fail), cond, kind) - case SWITCH(tags, labels) => SWITCH(tags, labels map inlinedBlock) - case RETURN(_) => JUMP(afterBlock) - case LOAD_LOCAL(l) if isInlined(l) => LOAD_LOCAL(inlinedLocals(l)) - case STORE_LOCAL(l) if isInlined(l) => STORE_LOCAL(inlinedLocals(l)) - case LOAD_LOCAL(l) => assertLocal(l) - case STORE_LOCAL(l) => assertLocal(l) - case SCOPE_ENTER(l) if isInlined(l) => SCOPE_ENTER(inlinedLocals(l)) - case SCOPE_EXIT(l) if isInlined(l) => SCOPE_EXIT(inlinedLocals(l)) - - case nw @ NEW(sym) => - val r = NEW(sym) - pending(nw.init) = r - r - - case CALL_METHOD(meth, Static(true)) if meth.isClassConstructor => - CALL_METHOD(meth, Static(onInstance = true)) - - case _ => i.clone() - } - // check any pending NEW's - pending remove i foreach (_.init = newInstr.asInstanceOf[CALL_METHOD]) - newInstr - } - - caller addLocals (inc.locals map dupLocal) - caller addLocal inlinedThis - - if (retVal ne null) - caller addLocal retVal - - inc.m foreachBlock { b => - inlinedBlock += (b -> newBlock()) - inlinedBlock(b).varsInScope ++= (b.varsInScope map inlinedLocals) - } - - // re-emit the instructions before the call - block.open() - block.clear() - block emit instrBefore - - // store the arguments into special locals - inc.m.params.reverse foreach (p => blockEmit(STORE_LOCAL(inlinedLocals(p)))) - blockEmit(STORE_LOCAL(inlinedThis)) - - // jump to the start block of the callee - blockEmit(JUMP(inlinedBlock(inc.m.startBlock))) - block.close() - - // duplicate the other blocks in the callee - val calleeLin = inc.m.linearizedBlocks() - calleeLin foreach { bb => - var info = if(hasRETURN) (a in bb) else null - def emitInlined(i: Instruction) = inlinedBlock(bb).emit(i, targetPos) - def emitDrops(toDrop: Int) = info.stack.types drop toDrop foreach (t => emitInlined(DROP(t))) - - for (i <- bb) { - i match { - case RETURN(UNIT) => emitDrops(0) - case RETURN(kind) => - if (info.stack.length > 1) { - emitInlined(STORE_LOCAL(retVal)) - emitDrops(1) - emitInlined(LOAD_LOCAL(retVal)) - } - case _ => () - } - emitInlined(map(i)) - info = if(hasRETURN) a.interpret(info, i) else null - } - inlinedBlock(bb).close() - } - - afterBlock emit instrAfter - afterBlock.close() - - staleIn += afterBlock - splicedBlocks ++= (calleeLin map inlinedBlock) - - // add exception handlers of the callee - caller addHandlers (inc.handlers map translateExh) - assert(pending.isEmpty, "Pending NEW elements: " + pending) - if (settings.debug) icodes.checkValid(caller.m) - } - - def isStampedForInlining(stackLength: Int): InlineSafetyInfo = { - - if(tfa.blackballed(inc.sym)) { return NeverSafeToInline } - - if(!isKnownToInlineSafely) { - - if(inc.openBlocks.nonEmpty) { - val msg = ("Encountered " + inc.openBlocks.size + " open block(s) in isSafeToInline: this indicates a bug in the optimizer!\n" + - " caller = " + caller.m + ", callee = " + inc.m) - warn(inc.sym.pos, msg) - tfa.knownNever += inc.sym - return DontInlineHere("Open blocks in " + inc.m) - } - - val reasonWhyNever: String = { - var rs: List[String] = Nil - if(inc.isRecursive) { rs ::= "is recursive" } - if(isInlineForbidden) { rs ::= "is annotated @noinline" } - if(inc.isSynchronized) { rs ::= "is synchronized method" } - if(inc.m.bytecodeHasEHs) { rs ::= "bytecode contains exception handlers / finally clause" } // SI-6188 - if(inc.m.bytecodeHasInvokeDynamic) { rs ::= "bytecode contains invoke dynamic" } - if(rs.isEmpty) null else rs.mkString("", ", and ", "") - } - - if(reasonWhyNever != null) { - tfa.knownNever += inc.sym - inlineLog("never", inc.sym, reasonWhyNever) - // next time around NeverSafeToInline is returned, thus skipping (duplicate) msg, this is intended. - return DontInlineHere(inc.m + " " + reasonWhyNever) - } - - if(sameSymbols) { // TODO but this also amounts to recursive, ie should lead to adding to tfa.knownNever, right? - tfa.knownUnsafe += inc.sym - return DontInlineHere("sameSymbols (ie caller == callee)") - } - - } - - /* - * From here on, two main categories of checks remain, (a) and (b) below: - * (a.1) either the scoring heuristics give green light; or - * (a.2) forced as candidate due to @inline. - * After that, safety proper is checked: - * (b.1) the callee does not contain calls to private methods when called from another class - * (b.2) the callee is not going to be inlined into a position with non-empty stack, - * while having a top-level finalizer (see liftedTry problem) - * As a result of (b), some synthetic private members can be chosen to become public. - */ - - val score = inlinerScore - val scoreStr = if (score > 0) "+" + score else "" + score - val what = if (score > 0) "ok to" else "don't" - inlineLog(scoreStr, inc.m.symbol, s"$what inline into ${ownedName(caller.m.symbol)}") - - if (!isInlineForced && score <= 0) { - // During inlining retry, a previous caller-callee pair that scored low may pass. - // Thus, adding the callee to tfa.knownUnsafe isn't warranted. - return DontInlineHere(s"inliner heuristic") - } - - if(inc.hasHandlers && (stackLength > inc.minimumStack)) { - return DontInlineHere("callee contains exception handlers / finally clause, and is invoked with non-empty operand stack") // SI-6157 - } - - if(isKnownToInlineSafely) { return InlineableAtThisCaller } - - if(stackLength > inc.minimumStack && inc.hasNonFinalizerHandler) { - val msg = "method " + inc.sym + " is used on a non-empty stack with finalizer." - debuglog(msg) - // FYI: not reason enough to add inc.sym to tfa.knownUnsafe (because at other callsite in this caller, inlining might be ok) - return DontInlineHere(msg) - } - - val accReq = inc.accessRequirements - if(!canAccess(accReq.accessNeeded)) { - tfa.knownUnsafe += inc.sym - val msg = "access level required by callee not matched by caller" - inlineLog("fail", inc.sym, msg) - return DontInlineHere(msg) - } - - FeasibleInline(accReq.accessNeeded, accReq.toBecomePublic) - - } - - def canAccess(level: NonPublicRefs.Value) = level match { - case Private => caller.owner == inc.owner - case Protected => caller.owner.tpe <:< inc.owner.tpe - case Public => true - } - private def sameSymbols = caller.sym == inc.sym - - /** Gives green light for inlining (which may still be vetoed later). Heuristics: - * - it's bad to make the caller larger (> SMALL_METHOD_SIZE) if it was small - * - it's bad to inline large methods - * - it's good to inline higher order functions - * - it's good to inline closures functions. - * - it's bad (useless) to inline inside bridge methods - */ - def inlinerScore: Int = { - var score = 0 - - // better not inline inside closures, but hope that the closure itself is repeatedly inlined - if (caller.isInClosure) score -= 2 - else if (caller.inlinedCalls < 1) score -= 1 // only monadic methods can trigger the first inline - - if (inc.isSmall) score += 1 - // if (inc.hasClosureParam) score += 2 - if (inc.isLarge) score -= 1 - if (caller.isSmall && isLargeSum) { - score -= 1 - debuglog(s"inliner score decreased to $score because small caller $caller would become large") - } - - if (inc.isMonadic) score += 3 - else if (inc.isHigherOrder) score += 1 - - if (inc.isInClosure) score += 2 - if (inlinedMethodCount(inc.sym) > 2) score -= 2 - score - } - } - - def lookupIMethod(meth: Symbol, receiver: Symbol): Option[IMethod] = { - def tryParent(sym: Symbol) = icodes icode sym flatMap (_ lookupMethod meth) - - (receiver.info.baseClasses.iterator map tryParent find (_.isDefined)).flatten - } - } /* class Inliner */ -} /* class Inliners */ |