diff options
Diffstat (limited to 'src/compiler/scala/tools/nsc/backend/icode/GenICode.scala')
| -rw-r--r-- | src/compiler/scala/tools/nsc/backend/icode/GenICode.scala | 152 |
1 files changed, 51 insertions, 101 deletions
diff --git a/src/compiler/scala/tools/nsc/backend/icode/GenICode.scala b/src/compiler/scala/tools/nsc/backend/icode/GenICode.scala index ea4e8475f9..f07c331fb0 100644 --- a/src/compiler/scala/tools/nsc/backend/icode/GenICode.scala +++ b/src/compiler/scala/tools/nsc/backend/icode/GenICode.scala @@ -13,10 +13,8 @@ import scala.collection.mutable.{ ListBuffer, Buffer } import scala.tools.nsc.symtab._ import scala.annotation.switch import PartialFunction._ -import scala.language.postfixOps -/** This class ... - * +/** * @author Iulian Dragos * @version 1.0 */ @@ -160,8 +158,6 @@ abstract class GenICode extends SubComponent { * and not produce any value. Use genLoad for expressions which leave * a value on top of the stack. * - * @param tree ... - * @param ctx ... * @return a new context. This is necessary for control flow instructions * which may change the current basic block. */ @@ -264,11 +260,6 @@ abstract class GenICode extends SubComponent { } /** Generate primitive array operations. - * - * @param tree ... - * @param ctx ... - * @param code ... - * @return ... */ private def genArrayOp(tree: Tree, ctx: Context, code: Int, expectedType: TypeKind): (Context, TypeKind) = { import scalaPrimitives._ @@ -432,7 +423,7 @@ abstract class GenICode extends SubComponent { private def genPrimitiveOp(tree: Apply, ctx: Context, expectedType: TypeKind): (Context, TypeKind) = { val sym = tree.symbol - val Apply(fun @ Select(receiver, _), args) = tree + val Apply(fun @ Select(receiver, _), _) = tree val code = scalaPrimitives.getPrimitive(sym, receiver.tpe) if (scalaPrimitives.isArithmeticOp(code)) @@ -543,9 +534,8 @@ abstract class GenICode extends SubComponent { // emits CIL_LOAD_ARRAY_ITEM_ADDRESS case Apply(fun, args) => if (isPrimitive(fun.symbol)) { - val sym = tree.symbol - val Apply(fun @ Select(receiver, _), args) = tree + val Select(receiver, _) = fun val code = scalaPrimitives.getPrimitive(sym, receiver.tpe) if (isArrayOp(code)) { @@ -858,7 +848,7 @@ abstract class GenICode extends SubComponent { // 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 - var loc1 = ctx.makeLocal(tree.pos, expr.tpe, "boxed") + val loc1 = ctx.makeLocal(tree.pos, expr.tpe, "boxed") ctx1.bb.emit(STORE_LOCAL(loc1)) ctx1.bb.emit(LOAD_LOCAL(loc1)) } @@ -1104,7 +1094,7 @@ abstract class GenICode extends SubComponent { case Match(selector, cases) => def genLoadMatch = { debuglog("Generating SWITCH statement."); - var 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 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 var caseCtx: Context = null generatedType = toTypeKind(tree.tpe) @@ -1163,34 +1153,30 @@ abstract class GenICode extends SubComponent { resCtx } - private def adapt(from: TypeKind, to: TypeKind, ctx: Context, pos: Position): Unit = { - if (!(from <:< to) && !(from == NullReference && to == NothingReference)) { - to match { - case UNIT => - ctx.bb.emit(DROP(from), pos) - debuglog("Dropped an " + from); - - case _ => - debugassert(from != UNIT, "Can't convert from UNIT to " + to + " at: " + pos) - assert(!from.isReferenceType && !to.isReferenceType, - "type error: can't convert from " + from + " to " + to +" in unit " + unit.source + " at " + pos) - - ctx.bb.emit(CALL_PRIMITIVE(Conversion(from, to)), pos) - } - } else if (from == NothingReference) { - ctx.bb.emit(THROW(ThrowableClass)) - ctx.bb.enterIgnoreMode - } else if (from == NullReference) { - ctx.bb.emit(DROP(from)) - ctx.bb.emit(CONSTANT(Constant(null))) + 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. + log(s"GenICode#adapt($from, $to, $ctx, $pos)") + + val conforms = (from <:< to) || (from == NullReference && to == NothingReference) + def coerce(from: TypeKind, to: TypeKind) = ctx.bb.emit(CALL_PRIMITIVE(Conversion(from, to)), pos) + def checkAssertions() { + def msg = s"Can't convert from $from to $to in unit ${unit.source} at $pos" + debugassert(from != UNIT, msg) + assert(!from.isReferenceType && !to.isReferenceType, msg) } - else if (from == ThrowableReference && !(ThrowableClass.tpe <:< to.toType)) { - log("Inserted check-cast on throwable to " + to + " at " + pos) - ctx.bb.emit(CHECK_CAST(to)) + if (conforms) from match { + case NothingReference => ctx.bb.emit(THROW(ThrowableClass)) ; ctx.bb.enterIgnoreMode + case NullReference => ctx.bb.emit(Seq(DROP(from), CONSTANT(Constant(null)))) + case ThrowableReference if !(ThrowableClass.tpe <:< to.toType) => ctx.bb.emit(CHECK_CAST(to)) // downcast throwables + case _ => + // widen subrange types + if (from.isIntSizedType && to == LONG) + coerce(INT, LONG) } - else (from, to) match { - case (BYTE, LONG) | (SHORT, LONG) | (CHAR, LONG) | (INT, LONG) => ctx.bb.emit(CALL_PRIMITIVE(Conversion(INT, LONG))) - case _ => () + else to match { + case UNIT => ctx.bb.emit(DROP(from), pos) // value discarding + case _ => checkAssertions() ; coerce(from, to) // other primitive coercions } } @@ -1257,8 +1243,11 @@ abstract class GenICode extends SubComponent { val sym = ( if (!tree.symbol.isPackageClass) tree.symbol else tree.symbol.info.member(nme.PACKAGE) match { - case NoSymbol => assert(false, "Cannot use package as value: " + tree) ; NoSymbol - case s => debugwarn("Bug: found package class where package object expected. Converting.") ; s.moduleClass + 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)) @@ -1392,10 +1381,6 @@ abstract class GenICode extends SubComponent { // } /** Generate string concatenation. - * - * @param tree ... - * @param ctx ... - * @return ... */ def genStringConcat(tree: Tree, ctx: Context): Context = { liftStringConcat(tree) match { @@ -1709,8 +1694,6 @@ abstract class GenICode extends SubComponent { * 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. - * - * @param method ... */ def prune(method: IMethod) = { var changed = false @@ -1906,18 +1889,8 @@ abstract class GenICode extends SubComponent { var handlerCount = 0 - override def toString(): String = { - val buf = new StringBuilder() - buf.append("\tpackage: ").append(packg).append('\n') - buf.append("\tclazz: ").append(clazz).append('\n') - buf.append("\tmethod: ").append(method).append('\n') - buf.append("\tbb: ").append(bb).append('\n') - buf.append("\tlabels: ").append(labels).append('\n') - buf.append("\texception handlers: ").append(handlers).append('\n') - buf.append("\tcleanups: ").append(cleanups).append('\n') - buf.append("\tscope: ").append(scope).append('\n') - buf.toString() - } + 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) @@ -1976,18 +1949,7 @@ abstract class GenICode extends SubComponent { this } - def removeFinalizer(f: Tree): this.type = { - assert(cleanups.head contains f, - "Illegal nesting of cleanup operations: " + cleanups + " while exiting finalizer " + f); - cleanups = cleanups.tail - this - } - /** Prepare a new context upon entry into a method. - * - * @param m ... - * @param d ... - * @return ... */ def enterMethod(m: IMethod, d: DefDef): Context = { val ctx1 = new Context(this) setMethod(m) @@ -2059,16 +2021,6 @@ abstract class GenICode extends SubComponent { currentExceptionHandlers = currentExceptionHandlers.tail } - /** Remove the given handler from the list of active exception handlers. */ - def removeActiveHandler(exh: ExceptionHandler): Unit = { - assert(handlerCount > 0 && handlers.head == exh, - "Wrong nesting of exception handlers." + this + " for " + exh) - handlerCount -= 1 - handlers = handlers.tail - debuglog("removed handler: " + exh); - - } - /** Clone the current context */ def dup: Context = new Context(this) @@ -2087,14 +2039,14 @@ abstract class GenICode extends SubComponent { * It returns the resulting context, with the same active handlers as * before the call. Use it like: * - * <code> ctx.Try( ctx => { + * ` ctx.Try( ctx => { * ctx.bb.emit(...) // protected block * }, (ThrowableClass, * ctx => { * ctx.bb.emit(...); // exception handler * }), (AnotherExceptionClass, * ctx => {... - * } ))</code> + * } ))` */ def Try(body: Context => Context, handlers: List[(Symbol, TypeKind, Context => Context)], @@ -2130,7 +2082,7 @@ abstract class GenICode extends SubComponent { } else ctx - val finalizerExh = if (finalizer != EmptyTree) Some({ + if (finalizer != EmptyTree) { val exh = outerCtx.newExceptionHandler(NoSymbol, toTypeKind(finalizer.tpe), finalizer.pos) // finalizer covers exception handlers this.addActiveHandler(exh) // .. and body aswell val ctx = finalizerCtx.enterExceptionHandler(exh) @@ -2143,21 +2095,20 @@ abstract class GenICode extends SubComponent { ctx1.bb.enterIgnoreMode; ctx1.bb.close finalizerCtx.endHandler() - exh - }) else None - - val exhs = handlers.map { case (sym, kind, handler) => // def genWildcardHandler(sym: Symbol): (Symbol, TypeKind, Context => Context) = - val exh = this.newExceptionHandler(sym, kind, tree.pos) - var ctx1 = outerCtx.enterExceptionHandler(exh) - ctx1.addFinalizer(finalizer, finalizerCtx) - loadException(ctx1, exh, tree.pos) - ctx1 = handler(ctx1) - // emit finalizer - val ctx2 = emitFinalizer(ctx1) - ctx2.bb.closeWith(JUMP(afterCtx.bb)) - outerCtx.endHandler() - exh - } + } + + for ((sym, kind, handler) <- handlers) { + val exh = this.newExceptionHandler(sym, kind, tree.pos) + var ctx1 = outerCtx.enterExceptionHandler(exh) + ctx1.addFinalizer(finalizer, finalizerCtx) + loadException(ctx1, exh, tree.pos) + ctx1 = handler(ctx1) + // emit finalizer + val ctx2 = emitFinalizer(ctx1) + ctx2.bb.closeWith(JUMP(afterCtx.bb)) + outerCtx.endHandler() + } + val bodyCtx = this.newBlock if (finalizer != EmptyTree) bodyCtx.addFinalizer(finalizer, finalizerCtx) @@ -2356,7 +2307,6 @@ abstract class GenICode extends SubComponent { val locals: ListBuffer[Local] = new ListBuffer def add(l: Local) = locals += l - def remove(l: Local) = locals -= l /** Return all locals that are in scope. */ def varsInScope: Buffer[Local] = outer.varsInScope.clone() ++= locals |