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author | Grzegorz Kossakowski <grzegorz.kossakowski@gmail.com> | 2013-08-28 13:34:32 -0700 |
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committer | Grzegorz Kossakowski <grzegorz.kossakowski@gmail.com> | 2013-08-28 13:34:32 -0700 |
commit | 8a292cb6eed15828762ed8291c723199da5100e5 (patch) | |
tree | 2ceaf5fb1546604d1178c866ce46c2d67c10ea3c /src | |
parent | a24fc60deed8fbed062ecd6ff96e434349cca75d (diff) | |
parent | 3b3f03749a15afad7b5428cc53bea0a5e759f94d (diff) | |
download | scala-8a292cb6eed15828762ed8291c723199da5100e5.tar.gz scala-8a292cb6eed15828762ed8291c723199da5100e5.tar.bz2 scala-8a292cb6eed15828762ed8291c723199da5100e5.zip |
Merge pull request #2863 from magarciaEPFL/backendish40
(1 of 2) of the rest of the new bytecode emitter + feedback
Diffstat (limited to 'src')
-rw-r--r-- | src/compiler/scala/tools/nsc/backend/jvm/GenBCode.scala | 328 |
1 files changed, 253 insertions, 75 deletions
diff --git a/src/compiler/scala/tools/nsc/backend/jvm/GenBCode.scala b/src/compiler/scala/tools/nsc/backend/jvm/GenBCode.scala index e55a3baed0..193100474c 100644 --- a/src/compiler/scala/tools/nsc/backend/jvm/GenBCode.scala +++ b/src/compiler/scala/tools/nsc/backend/jvm/GenBCode.scala @@ -17,13 +17,25 @@ import scala.tools.asm /* * Prepare in-memory representations of classfiles using the ASM Tree API, and serialize them to disk. * - * `BCodePhase.apply(CompilationUnit)` is invoked by some external force and that sets in motion: - * - visiting each ClassDef contained in that CompilationUnit - * - lowering the ClassDef into: + * Three pipelines are at work, each taking work items from a queue dedicated to that pipeline: + * + * (There's another pipeline so to speak, the one that populates queue-1 by traversing a CompilationUnit until ClassDefs are found, + * but the "interesting" pipelines are the ones described below) + * + * (1) In the first queue, an item consists of a ClassDef along with its arrival position. + * This position is needed at the time classfiles are serialized to disk, + * so as to emit classfiles in the same order CleanUp handed them over. + * As a result, two runs of the compiler on the same files produce jars that are identical on a byte basis. + * See `ant test.stability` + * + * (2) The second queue contains items where a ClassDef has been lowered into: * (a) an optional mirror class, * (b) a plain class, and * (c) an optional bean class. - * - each of the ClassNodes above is lowered into a byte-array (ie into a classfile) and serialized. + * + * (3) The third queue contains items ready for serialization. + * It's a priority queue that follows the original arrival order, + * so as to emit identical jars on repeated compilation of the same sources. * * Plain, mirror, and bean classes are built respectively by PlainClassBuilder, JMirrorBuilder, and JBeanInfoBuilder. * @@ -50,75 +62,192 @@ abstract class GenBCode extends BCodeSyncAndTry { private var mirrorCodeGen : JMirrorBuilder = null private var beanInfoCodeGen : JBeanInfoBuilder = null - private var needsOutFolder = false // whether getOutFolder(claszSymbol) should be invoked for each claszSymbol + /* ---------------- q1 ---------------- */ + + case class Item1(arrivalPos: Int, cd: ClassDef, cunit: CompilationUnit) { + def isPoison = { arrivalPos == Int.MaxValue } + } + private val poison1 = Item1(Int.MaxValue, null, null) + private val q1 = new java.util.LinkedList[Item1] + + /* ---------------- q2 ---------------- */ - val caseInsensitively = mutable.Map.empty[String, Symbol] + case class Item2(arrivalPos: Int, + mirror: asm.tree.ClassNode, + plain: asm.tree.ClassNode, + bean: asm.tree.ClassNode, + outFolder: scala.tools.nsc.io.AbstractFile) { + def isPoison = { arrivalPos == Int.MaxValue } + } + + private val poison2 = Item2(Int.MaxValue, null, null, null, null) + private val q2 = new _root_.java.util.LinkedList[Item2] + + /* ---------------- q3 ---------------- */ /* - * Checks for duplicate internal names case-insensitively, - * builds ASM ClassNodes for mirror, plain, and bean classes. + * An item of queue-3 (the last queue before serializing to disk) contains three of these + * (one for each of mirror, plain, and bean classes). * + * @param jclassName internal name of the class + * @param jclassBytes bytecode emitted for the class SubItem3 represents */ - def visit(arrivalPos: Int, cd: ClassDef, cunit: CompilationUnit) { - val claszSymbol = cd.symbol - - // GenASM checks this before classfiles are emitted, https://github.com/scala/scala/commit/e4d1d930693ac75d8eb64c2c3c69f2fc22bec739 - val lowercaseJavaClassName = claszSymbol.javaClassName.toLowerCase - caseInsensitively.get(lowercaseJavaClassName) match { - case None => - caseInsensitively.put(lowercaseJavaClassName, claszSymbol) - case Some(dupClassSym) => - cunit.warning( - claszSymbol.pos, - s"Class ${claszSymbol.javaClassName} differs only in case from ${dupClassSym.javaClassName}. " + - "Such classes will overwrite one another on case-insensitive filesystems." - ) + case class SubItem3( + jclassName: String, + jclassBytes: Array[Byte] + ) + + case class Item3(arrivalPos: Int, + mirror: SubItem3, + plain: SubItem3, + bean: SubItem3, + outFolder: scala.tools.nsc.io.AbstractFile) { + + def isPoison = { arrivalPos == Int.MaxValue } + } + private val i3comparator = new java.util.Comparator[Item3] { + override def compare(a: Item3, b: Item3) = { + if (a.arrivalPos < b.arrivalPos) -1 + else if (a.arrivalPos == b.arrivalPos) 0 + else 1 } + } + private val poison3 = Item3(Int.MaxValue, null, null, null, null) + private val q3 = new java.util.PriorityQueue[Item3](1000, i3comparator) + + /* + * Pipeline that takes ClassDefs from queue-1, lowers them into an intermediate form, placing them on queue-2 + */ + class Worker1(needsOutFolder: Boolean) { + + val caseInsensitively = mutable.Map.empty[String, Symbol] - // -------------- mirror class, if needed -------------- - val mirrorC = - if (isStaticModule(claszSymbol) && isTopLevelModule(claszSymbol)) { - if (claszSymbol.companionClass == NoSymbol) { - mirrorCodeGen.genMirrorClass(claszSymbol, cunit) - } else { - log(s"No mirror class for module with linked class: ${claszSymbol.fullName}"); - null + def run() { + while (true) { + val item = q1.poll + if (item.isPoison) { + q2 add poison2 + return } - } else null - - // -------------- "plain" class -------------- - val pcb = new PlainClassBuilder(cunit) - pcb.genPlainClass(cd) - val outF = if (needsOutFolder) getOutFolder(claszSymbol, pcb.thisName, cunit) else null; - val plainC = pcb.cnode - - // -------------- bean info class, if needed -------------- - val beanC = - if (claszSymbol hasAnnotation BeanInfoAttr) { - beanInfoCodeGen.genBeanInfoClass( - claszSymbol, cunit, - fieldSymbols(claszSymbol), - methodSymbols(cd) - ) - } else null - - // ----------- serialize classfiles to disk - - def getByteArray(cn: asm.tree.ClassNode): Array[Byte] = { - val cw = new CClassWriter(extraProc) - cn.accept(cw) - cw.toByteArray + else { + try { visit(item) } + catch { + case ex: Throwable => + ex.printStackTrace() + error(s"Error while emitting ${item.cunit.source}\n${ex.getMessage}") + } + } + } } - if (mirrorC != null) { - sendToDisk(mirrorC.name, getByteArray(mirrorC), outF) + /* + * Checks for duplicate internal names case-insensitively, + * builds ASM ClassNodes for mirror, plain, and bean classes; + * enqueues them in queue-2. + * + */ + def visit(item: Item1) { + val Item1(arrivalPos, cd, cunit) = item + val claszSymbol = cd.symbol + + // GenASM checks this before classfiles are emitted, https://github.com/scala/scala/commit/e4d1d930693ac75d8eb64c2c3c69f2fc22bec739 + val lowercaseJavaClassName = claszSymbol.javaClassName.toLowerCase + caseInsensitively.get(lowercaseJavaClassName) match { + case None => + caseInsensitively.put(lowercaseJavaClassName, claszSymbol) + case Some(dupClassSym) => + item.cunit.warning( + claszSymbol.pos, + s"Class ${claszSymbol.javaClassName} differs only in case from ${dupClassSym.javaClassName}. " + + "Such classes will overwrite one another on case-insensitive filesystems." + ) + } + + // -------------- mirror class, if needed -------------- + val mirrorC = + if (isStaticModule(claszSymbol) && isTopLevelModule(claszSymbol)) { + if (claszSymbol.companionClass == NoSymbol) { + mirrorCodeGen.genMirrorClass(claszSymbol, cunit) + } else { + log(s"No mirror class for module with linked class: ${claszSymbol.fullName}") + null + } + } else null + + // -------------- "plain" class -------------- + val pcb = new PlainClassBuilder(cunit) + pcb.genPlainClass(cd) + val outF = if (needsOutFolder) getOutFolder(claszSymbol, pcb.thisName, cunit) else null; + val plainC = pcb.cnode + + // -------------- bean info class, if needed -------------- + val beanC = + if (claszSymbol hasAnnotation BeanInfoAttr) { + beanInfoCodeGen.genBeanInfoClass( + claszSymbol, cunit, + fieldSymbols(claszSymbol), + methodSymbols(cd) + ) + } else null + + // ----------- hand over to pipeline-2 + + val item2 = + Item2(arrivalPos, + mirrorC, plainC, beanC, + outF) + + q2 add item2 // at the very end of this method so that no Worker2 thread starts mutating before we're done. + + } // end of method visit(Item1) + + } // end of class BCodePhase.Worker1 + + /* + * Pipeline that takes ClassNodes from queue-2. The unit of work depends on the optimization level: + * + * (a) no optimization involves: + * - converting the plain ClassNode to byte array and placing it on queue-3 + */ + class Worker2 { + + def run() { + while (true) { + val item = q2.poll + if (item.isPoison) { + q3 add poison3 + return + } + else { + try { addToQ3(item) } + catch { + case ex: Throwable => + ex.printStackTrace() + error(s"Error while emitting ${item.plain.name}\n${ex.getMessage}") + } + } + } } - sendToDisk(plainC.name, getByteArray(plainC), outF) - if (beanC != null) { - sendToDisk(beanC.name, getByteArray(beanC), outF) + + private def addToQ3(item: Item2) { + + def getByteArray(cn: asm.tree.ClassNode): Array[Byte] = { + val cw = new CClassWriter(extraProc) + cn.accept(cw) + cw.toByteArray + } + + 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)) + val beanC = if (bean == null) null else SubItem3(bean.name, getByteArray(bean)) + + q3 add Item3(arrivalPos, mirrorC, plainC, beanC, outFolder) + } - } // end of method visit() + } // end of class BCodePhase.Worker2 var arrivalPos = 0 @@ -144,15 +273,12 @@ abstract class GenBCode extends BCodeSyncAndTry { mirrorCodeGen = new JMirrorBuilder beanInfoCodeGen = new JBeanInfoBuilder - needsOutFolder = bytecodeWriter.isInstanceOf[ClassBytecodeWriter] - - super.run() + val needsOutfileForSymbol = bytecodeWriter.isInstanceOf[ClassBytecodeWriter] + buildAndSendToDisk(needsOutfileForSymbol) // closing output files. bytecodeWriter.close() - caseInsensitively.clear() - /* TODO Bytecode can be verified (now that all classfiles have been written to disk) * * (1) asm.util.CheckAdapter.verify() @@ -170,17 +296,69 @@ abstract class GenBCode extends BCodeSyncAndTry { clearBCodeTypes() } - def sendToDisk(jclassName: String, jclassBytes: Array[Byte], outFolder: _root_.scala.tools.nsc.io.AbstractFile) { - try { - val outFile = - if (outFolder == null) null - else getFileForClassfile(outFolder, jclassName, ".class") - bytecodeWriter.writeClass(jclassName, jclassName, jclassBytes, outFile) + /* + * Sequentially: + * (a) place all ClassDefs in queue-1 + * (b) dequeue one at a time from queue-1, convert it to ASM ClassNode, place in queue-2 + * (c) dequeue one at a time from queue-2, convert it to byte-array, place in queue-3 + * (d) serialize to disk by draining queue-3. + */ + private def buildAndSendToDisk(needsOutFolder: Boolean) { + + feedPipeline1() + (new Worker1(needsOutFolder)).run() + (new Worker2).run() + drainQ3() + + } + + /* Feed pipeline-1: place all ClassDefs on q1, recording their arrival position. */ + private def feedPipeline1() { + super.run() + q1 add poison1 + } + + /* Pipeline that writes classfile representations to disk. */ + private def drainQ3() { + + def sendToDisk(cfr: SubItem3, outFolder: scala.tools.nsc.io.AbstractFile) { + if (cfr != null){ + val SubItem3(jclassName, jclassBytes) = cfr + try { + val outFile = + if (outFolder == null) null + else getFileForClassfile(outFolder, jclassName, ".class") + bytecodeWriter.writeClass(jclassName, jclassName, jclassBytes, outFile) + } + catch { + case e: FileConflictException => + error(s"error writing $jclassName: ${e.getMessage}") + } + } } - catch { - case e: FileConflictException => - error(s"error writing $jclassName: ${e.getMessage}") + + var moreComing = true + // `expected` denotes the arrivalPos whose Item3 should be serialized next + var expected = 0 + + while (moreComing) { + val incoming = q3.poll + moreComing = !incoming.isPoison + if (moreComing) { + val item = incoming + val outFolder = item.outFolder + sendToDisk(item.mirror, outFolder) + sendToDisk(item.plain, outFolder) + sendToDisk(item.bean, outFolder) + expected += 1 + } } + + // we're done + assert(q1.isEmpty, s"Some ClassDefs remained in the first queue: $q1") + assert(q2.isEmpty, s"Some classfiles remained in the second queue: $q2") + assert(q3.isEmpty, s"Some classfiles weren't written to disk: $q3") + } override def apply(cunit: CompilationUnit): Unit = { @@ -190,7 +368,7 @@ abstract class GenBCode extends BCodeSyncAndTry { case EmptyTree => () case PackageDef(_, stats) => stats foreach gen case cd: ClassDef => - visit(arrivalPos, cd, cunit) + q1 add Item1(arrivalPos, cd, cunit) arrivalPos += 1 } } |