Mercurial > hg > graal-compiler
changeset 22552:bf3386380b45
TraceRA: remove LinearScanLifetimeAnalysisPhase.
| author | Josef Eisl <josef.eisl@jku.at> |
|---|---|
| date | Mon, 31 Aug 2015 15:10:29 +0200 |
| parents | f966e9701a33 |
| children | 481574c6185b |
| files | graal/com.oracle.graal.lir/src/com/oracle/graal/lir/alloc/trace/LinearScanLifetimeAnalysisPhase.java graal/com.oracle.graal.lir/src/com/oracle/graal/lir/alloc/trace/TraceLinearScan.java graal/com.oracle.graal.lir/src/com/oracle/graal/lir/alloc/trace/TraceLinearScanLifetimeAnalysisPhase.java |
| diffstat | 3 files changed, 764 insertions(+), 954 deletions(-) [+] |
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--- a/graal/com.oracle.graal.lir/src/com/oracle/graal/lir/alloc/trace/LinearScanLifetimeAnalysisPhase.java Mon Aug 31 13:33:08 2015 +0200 +++ /dev/null Thu Jan 01 00:00:00 1970 +0000 @@ -1,838 +0,0 @@ -/* - * Copyright (c) 2015, 2015, Oracle and/or its affiliates. All rights reserved. - * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. - * - * This code is free software; you can redistribute it and/or modify it - * under the terms of the GNU General Public License version 2 only, as - * published by the Free Software Foundation. - * - * This code is distributed in the hope that it will be useful, but WITHOUT - * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or - * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License - * version 2 for more details (a copy is included in the LICENSE file that - * accompanied this code). - * - * You should have received a copy of the GNU General Public License version - * 2 along with this work; if not, write to the Free Software Foundation, - * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. - * - * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA - * or visit www.oracle.com if you need additional information or have any - * questions. - */ -package com.oracle.graal.lir.alloc.trace; - -import static com.oracle.graal.compiler.common.GraalOptions.*; -import static com.oracle.graal.lir.LIRValueUtil.*; -import static com.oracle.graal.lir.debug.LIRGenerationDebugContext.*; -import static jdk.internal.jvmci.code.ValueUtil.*; - -import java.util.*; - -import jdk.internal.jvmci.code.*; -import jdk.internal.jvmci.common.*; -import jdk.internal.jvmci.meta.*; - -import com.oracle.graal.compiler.common.alloc.*; -import com.oracle.graal.compiler.common.cfg.*; -import com.oracle.graal.compiler.common.util.*; -import com.oracle.graal.debug.*; -import com.oracle.graal.debug.Debug.Scope; -import com.oracle.graal.lir.*; -import com.oracle.graal.lir.LIRInstruction.OperandFlag; -import com.oracle.graal.lir.LIRInstruction.OperandMode; -import com.oracle.graal.lir.StandardOp.LoadConstantOp; -import com.oracle.graal.lir.StandardOp.StackStoreOp; -import com.oracle.graal.lir.StandardOp.ValueMoveOp; -import com.oracle.graal.lir.alloc.trace.Interval.RegisterPriority; -import com.oracle.graal.lir.alloc.trace.Interval.SpillState; -import com.oracle.graal.lir.alloc.trace.TraceLinearScan.BlockData; -import com.oracle.graal.lir.gen.*; -import com.oracle.graal.lir.gen.LIRGeneratorTool.SpillMoveFactory; -import com.oracle.graal.lir.phases.*; - -public class LinearScanLifetimeAnalysisPhase extends AllocationPhase { - - protected final TraceLinearScan allocator; - - /** - * @param linearScan - */ - protected LinearScanLifetimeAnalysisPhase(TraceLinearScan linearScan) { - allocator = linearScan; - } - - @Override - protected <B extends AbstractBlockBase<B>> void run(TargetDescription target, LIRGenerationResult lirGenRes, List<B> codeEmittingOrder, List<B> linearScanOrder, SpillMoveFactory spillMoveFactory, - RegisterAllocationConfig registerAllocationConfig) { - numberInstructions(); - allocator.printLir("Before register allocation", true); - computeLocalLiveSets(); - computeGlobalLiveSets(); - buildIntervals(); - } - - /** - * Bit set for each variable that is contained in each loop. - */ - private BitMap2D intervalInLoop; - - boolean isIntervalInLoop(int interval, int loop) { - return intervalInLoop.at(interval, loop); - } - - /** - * Numbers all instructions in all blocks. The numbering follows the - * {@linkplain ComputeBlockOrder linear scan order}. - */ - protected void numberInstructions() { - - allocator.initIntervals(); - - ValueConsumer setVariableConsumer = (value, mode, flags) -> { - if (isVariable(value)) { - allocator.getOrCreateInterval(asVariable(value)); - } - }; - - // Assign IDs to LIR nodes and build a mapping, lirOps, from ID to LIRInstruction node. - int numInstructions = 0; - for (AbstractBlockBase<?> block : allocator.sortedBlocks()) { - numInstructions += allocator.getLIR().getLIRforBlock(block).size(); - } - - // initialize with correct length - allocator.initOpIdMaps(numInstructions); - - int opId = 0; - int index = 0; - for (AbstractBlockBase<?> block : allocator.sortedBlocks()) { - allocator.initBlockData(block); - - List<LIRInstruction> instructions = allocator.getLIR().getLIRforBlock(block); - - int numInst = instructions.size(); - for (int j = 0; j < numInst; j++) { - LIRInstruction op = instructions.get(j); - op.setId(opId); - - allocator.putOpIdMaps(index, op, block); - assert allocator.instructionForId(opId) == op : "must match"; - - op.visitEachTemp(setVariableConsumer); - op.visitEachOutput(setVariableConsumer); - - index++; - opId += 2; // numbering of lirOps by two - } - } - assert index == numInstructions : "must match"; - assert (index << 1) == opId : "must match: " + (index << 1); - } - - /** - * Computes local live sets (i.e. {@link BlockData#liveGen} and {@link BlockData#liveKill}) - * separately for each block. - */ - void computeLocalLiveSets() { - int liveSize = allocator.liveSetSize(); - - intervalInLoop = new BitMap2D(allocator.operandSize(), allocator.numLoops()); - - // iterate all blocks - for (final AbstractBlockBase<?> block : allocator.sortedBlocks()) { - try (Indent indent = Debug.logAndIndent("compute local live sets for block %s", block)) { - - final BitSet liveGen = new BitSet(liveSize); - final BitSet liveKill = new BitSet(liveSize); - - List<LIRInstruction> instructions = allocator.getLIR().getLIRforBlock(block); - int numInst = instructions.size(); - - ValueConsumer useConsumer = (operand, mode, flags) -> { - if (isVariable(operand)) { - int operandNum = allocator.operandNumber(operand); - if (!liveKill.get(operandNum)) { - liveGen.set(operandNum); - if (Debug.isLogEnabled()) { - Debug.log("liveGen for operand %d(%s)", operandNum, operand); - } - } - if (block.getLoop() != null) { - intervalInLoop.setBit(operandNum, block.getLoop().getIndex()); - } - } - - if (DetailedAsserts.getValue()) { - verifyInput(block, liveKill, operand); - } - }; - ValueConsumer stateConsumer = (operand, mode, flags) -> { - if (TraceLinearScan.isVariableOrRegister(operand)) { - int operandNum = allocator.operandNumber(operand); - if (!liveKill.get(operandNum)) { - liveGen.set(operandNum); - if (Debug.isLogEnabled()) { - Debug.log("liveGen in state for operand %d(%s)", operandNum, operand); - } - } - } - }; - ValueConsumer defConsumer = (operand, mode, flags) -> { - if (isVariable(operand)) { - int varNum = allocator.operandNumber(operand); - liveKill.set(varNum); - if (Debug.isLogEnabled()) { - Debug.log("liveKill for operand %d(%s)", varNum, operand); - } - if (block.getLoop() != null) { - intervalInLoop.setBit(varNum, block.getLoop().getIndex()); - } - } - - if (DetailedAsserts.getValue()) { - /* - * Fixed intervals are never live at block boundaries, so they need not be - * processed in live sets. Process them only in debug mode so that this can - * be checked - */ - verifyTemp(liveKill, operand); - } - }; - - // iterate all instructions of the block - for (int j = 0; j < numInst; j++) { - final LIRInstruction op = instructions.get(j); - - try (Indent indent2 = Debug.logAndIndent("handle op %d: %s", op.id(), op)) { - op.visitEachInput(useConsumer); - op.visitEachAlive(useConsumer); - /* - * Add uses of live locals from interpreter's point of view for proper debug - * information generation. - */ - op.visitEachState(stateConsumer); - op.visitEachTemp(defConsumer); - op.visitEachOutput(defConsumer); - } - } // end of instruction iteration - - BlockData blockSets = allocator.getBlockData(block); - blockSets.liveGen = liveGen; - blockSets.liveKill = liveKill; - blockSets.liveIn = new BitSet(liveSize); - blockSets.liveOut = new BitSet(liveSize); - - if (Debug.isLogEnabled()) { - Debug.log("liveGen B%d %s", block.getId(), blockSets.liveGen); - Debug.log("liveKill B%d %s", block.getId(), blockSets.liveKill); - } - - } - } // end of block iteration - } - - private void verifyTemp(BitSet liveKill, Value operand) { - /* - * Fixed intervals are never live at block boundaries, so they need not be processed in live - * sets. Process them only in debug mode so that this can be checked - */ - if (isRegister(operand)) { - if (allocator.isProcessed(operand)) { - liveKill.set(allocator.operandNumber(operand)); - } - } - } - - private void verifyInput(AbstractBlockBase<?> block, BitSet liveKill, Value operand) { - /* - * Fixed intervals are never live at block boundaries, so they need not be processed in live - * sets. This is checked by these assertions to be sure about it. The entry block may have - * incoming values in registers, which is ok. - */ - if (isRegister(operand) && block != allocator.getLIR().getControlFlowGraph().getStartBlock()) { - if (allocator.isProcessed(operand)) { - assert liveKill.get(allocator.operandNumber(operand)) : "using fixed register that is not defined in this block"; - } - } - } - - /** - * Performs a backward dataflow analysis to compute global live sets (i.e. - * {@link BlockData#liveIn} and {@link BlockData#liveOut}) for each block. - */ - protected void computeGlobalLiveSets() { - try (Indent indent = Debug.logAndIndent("compute global live sets")) { - int numBlocks = allocator.blockCount(); - boolean changeOccurred; - boolean changeOccurredInBlock; - int iterationCount = 0; - BitSet liveOut = new BitSet(allocator.liveSetSize()); // scratch set for calculations - - /* - * Perform a backward dataflow analysis to compute liveOut and liveIn for each block. - * The loop is executed until a fixpoint is reached (no changes in an iteration). - */ - do { - changeOccurred = false; - - try (Indent indent2 = Debug.logAndIndent("new iteration %d", iterationCount)) { - - // iterate all blocks in reverse order - for (int i = numBlocks - 1; i >= 0; i--) { - AbstractBlockBase<?> block = allocator.blockAt(i); - BlockData blockSets = allocator.getBlockData(block); - - changeOccurredInBlock = false; - - /* liveOut(block) is the union of liveIn(sux), for successors sux of block. */ - int n = block.getSuccessorCount(); - if (n > 0) { - liveOut.clear(); - // block has successors - if (n > 0) { - for (AbstractBlockBase<?> successor : block.getSuccessors()) { - liveOut.or(allocator.getBlockData(successor).liveIn); - } - } - - if (!blockSets.liveOut.equals(liveOut)) { - /* - * A change occurred. Swap the old and new live out sets to avoid - * copying. - */ - BitSet temp = blockSets.liveOut; - blockSets.liveOut = liveOut; - liveOut = temp; - - changeOccurred = true; - changeOccurredInBlock = true; - } - } - - if (iterationCount == 0 || changeOccurredInBlock) { - /* - * liveIn(block) is the union of liveGen(block) with (liveOut(block) & - * !liveKill(block)). - * - * Note: liveIn has to be computed only in first iteration or if liveOut - * has changed! - */ - BitSet liveIn = blockSets.liveIn; - liveIn.clear(); - liveIn.or(blockSets.liveOut); - liveIn.andNot(blockSets.liveKill); - liveIn.or(blockSets.liveGen); - - if (Debug.isLogEnabled()) { - Debug.log("block %d: livein = %s, liveout = %s", block.getId(), liveIn, blockSets.liveOut); - } - } - } - iterationCount++; - - if (changeOccurred && iterationCount > 50) { - throw new BailoutException("too many iterations in computeGlobalLiveSets"); - } - } - } while (changeOccurred); - - if (DetailedAsserts.getValue()) { - verifyLiveness(); - } - - // check that the liveIn set of the first block is empty - AbstractBlockBase<?> startBlock = allocator.getLIR().getControlFlowGraph().getStartBlock(); - if (allocator.getBlockData(startBlock).liveIn.cardinality() != 0) { - if (DetailedAsserts.getValue()) { - reportFailure(numBlocks); - } - // bailout if this occurs in product mode. - throw new JVMCIError("liveIn set of first block must be empty: " + allocator.getBlockData(startBlock).liveIn); - } - } - } - - protected void reportFailure(int numBlocks) { - try (Scope s = Debug.forceLog()) { - try (Indent indent = Debug.logAndIndent("report failure")) { - - BitSet startBlockLiveIn = allocator.getBlockData(allocator.getLIR().getControlFlowGraph().getStartBlock()).liveIn; - try (Indent indent2 = Debug.logAndIndent("Error: liveIn set of first block must be empty (when this fails, variables are used before they are defined):")) { - for (int operandNum = startBlockLiveIn.nextSetBit(0); operandNum >= 0; operandNum = startBlockLiveIn.nextSetBit(operandNum + 1)) { - Interval interval = allocator.intervalFor(operandNum); - if (interval != null) { - Value operand = interval.operand; - Debug.log("var %d; operand=%s; node=%s", operandNum, operand, getSourceForOperandFromDebugContext(operand)); - } else { - Debug.log("var %d; missing operand", operandNum); - } - } - } - - // print some additional information to simplify debugging - for (int operandNum = startBlockLiveIn.nextSetBit(0); operandNum >= 0; operandNum = startBlockLiveIn.nextSetBit(operandNum + 1)) { - Interval interval = allocator.intervalFor(operandNum); - Value operand = null; - Object valueForOperandFromDebugContext = null; - if (interval != null) { - operand = interval.operand; - valueForOperandFromDebugContext = getSourceForOperandFromDebugContext(operand); - } - try (Indent indent2 = Debug.logAndIndent("---- Detailed information for var %d; operand=%s; node=%s ----", operandNum, operand, valueForOperandFromDebugContext)) { - - Deque<AbstractBlockBase<?>> definedIn = new ArrayDeque<>(); - HashSet<AbstractBlockBase<?>> usedIn = new HashSet<>(); - for (AbstractBlockBase<?> block : allocator.sortedBlocks()) { - if (allocator.getBlockData(block).liveGen.get(operandNum)) { - usedIn.add(block); - try (Indent indent3 = Debug.logAndIndent("used in block B%d", block.getId())) { - for (LIRInstruction ins : allocator.getLIR().getLIRforBlock(block)) { - try (Indent indent4 = Debug.logAndIndent("%d: %s", ins.id(), ins)) { - ins.forEachState((liveStateOperand, mode, flags) -> { - Debug.log("operand=%s", liveStateOperand); - return liveStateOperand; - }); - } - } - } - } - if (allocator.getBlockData(block).liveKill.get(operandNum)) { - definedIn.add(block); - try (Indent indent3 = Debug.logAndIndent("defined in block B%d", block.getId())) { - for (LIRInstruction ins : allocator.getLIR().getLIRforBlock(block)) { - Debug.log("%d: %s", ins.id(), ins); - } - } - } - } - - int[] hitCount = new int[numBlocks]; - - while (!definedIn.isEmpty()) { - AbstractBlockBase<?> block = definedIn.removeFirst(); - usedIn.remove(block); - for (AbstractBlockBase<?> successor : block.getSuccessors()) { - if (successor.isLoopHeader()) { - if (!block.isLoopEnd()) { - definedIn.add(successor); - } - } else { - if (++hitCount[successor.getId()] == successor.getPredecessorCount()) { - definedIn.add(successor); - } - } - } - } - try (Indent indent3 = Debug.logAndIndent("**** offending usages are in: ")) { - for (AbstractBlockBase<?> block : usedIn) { - Debug.log("B%d", block.getId()); - } - } - } - } - } - } catch (Throwable e) { - throw Debug.handle(e); - } - } - - protected void verifyLiveness() { - /* - * Check that fixed intervals are not live at block boundaries (live set must be empty at - * fixed intervals). - */ - for (AbstractBlockBase<?> block : allocator.sortedBlocks()) { - for (int j = 0; j <= allocator.maxRegisterNumber(); j++) { - assert !allocator.getBlockData(block).liveIn.get(j) : "liveIn set of fixed register must be empty"; - assert !allocator.getBlockData(block).liveOut.get(j) : "liveOut set of fixed register must be empty"; - assert !allocator.getBlockData(block).liveGen.get(j) : "liveGen set of fixed register must be empty"; - } - } - } - - protected void addUse(AllocatableValue operand, int from, int to, RegisterPriority registerPriority, LIRKind kind) { - if (!allocator.isProcessed(operand)) { - return; - } - - Interval interval = allocator.getOrCreateInterval(operand); - if (!kind.equals(LIRKind.Illegal)) { - interval.setKind(kind); - } - - interval.addRange(from, to); - - // Register use position at even instruction id. - interval.addUsePos(to & ~1, registerPriority); - - if (Debug.isLogEnabled()) { - Debug.log("add use: %s, from %d to %d (%s)", interval, from, to, registerPriority.name()); - } - } - - protected void addTemp(AllocatableValue operand, int tempPos, RegisterPriority registerPriority, LIRKind kind) { - if (!allocator.isProcessed(operand)) { - return; - } - - Interval interval = allocator.getOrCreateInterval(operand); - if (!kind.equals(LIRKind.Illegal)) { - interval.setKind(kind); - } - - interval.addRange(tempPos, tempPos + 1); - interval.addUsePos(tempPos, registerPriority); - interval.addMaterializationValue(null); - - if (Debug.isLogEnabled()) { - Debug.log("add temp: %s tempPos %d (%s)", interval, tempPos, RegisterPriority.MustHaveRegister.name()); - } - } - - protected void addDef(AllocatableValue operand, LIRInstruction op, RegisterPriority registerPriority, LIRKind kind) { - if (!allocator.isProcessed(operand)) { - return; - } - int defPos = op.id(); - - Interval interval = allocator.getOrCreateInterval(operand); - if (!kind.equals(LIRKind.Illegal)) { - interval.setKind(kind); - } - - Range r = interval.first(); - if (r.from <= defPos) { - /* - * Update the starting point (when a range is first created for a use, its start is the - * beginning of the current block until a def is encountered). - */ - r.from = defPos; - interval.addUsePos(defPos, registerPriority); - - } else { - /* - * Dead value - make vacuous interval also add register priority for dead intervals - */ - interval.addRange(defPos, defPos + 1); - interval.addUsePos(defPos, registerPriority); - if (Debug.isLogEnabled()) { - Debug.log("Warning: def of operand %s at %d occurs without use", operand, defPos); - } - } - - changeSpillDefinitionPos(op, operand, interval, defPos); - if (registerPriority == RegisterPriority.None && interval.spillState().ordinal() <= SpillState.StartInMemory.ordinal() && isStackSlot(operand)) { - // detection of method-parameters and roundfp-results - interval.setSpillState(SpillState.StartInMemory); - } - interval.addMaterializationValue(getMaterializedValue(op, operand, interval)); - - if (Debug.isLogEnabled()) { - Debug.log("add def: %s defPos %d (%s)", interval, defPos, registerPriority.name()); - } - } - - /** - * Optimizes moves related to incoming stack based arguments. The interval for the destination - * of such moves is assigned the stack slot (which is in the caller's frame) as its spill slot. - */ - protected void handleMethodArguments(LIRInstruction op) { - if (op instanceof ValueMoveOp) { - ValueMoveOp move = (ValueMoveOp) op; - if (optimizeMethodArgument(move.getInput())) { - StackSlot slot = asStackSlot(move.getInput()); - if (DetailedAsserts.getValue()) { - assert op.id() > 0 : "invalid id"; - assert allocator.blockForId(op.id()).getPredecessorCount() == 0 : "move from stack must be in first block"; - assert isVariable(move.getResult()) : "result of move must be a variable"; - - if (Debug.isLogEnabled()) { - Debug.log("found move from stack slot %s to %s", slot, move.getResult()); - } - } - - Interval interval = allocator.intervalFor(move.getResult()); - interval.setSpillSlot(slot); - interval.assignLocation(slot); - } - } else if (op instanceof StackStoreOp) { - StackStoreOp store = (StackStoreOp) op; - StackSlot slot = asStackSlot(store.getStackSlot()); - Interval interval = allocator.intervalFor(store.getResult()); - interval.setSpillSlot(slot); - interval.setSpillState(SpillState.StartInMemory); - } - } - - protected void addRegisterHint(final LIRInstruction op, final Value targetValue, OperandMode mode, EnumSet<OperandFlag> flags, final boolean hintAtDef) { - if (flags.contains(OperandFlag.HINT) && TraceLinearScan.isVariableOrRegister(targetValue)) { - - op.forEachRegisterHint(targetValue, mode, (registerHint, valueMode, valueFlags) -> { - if (TraceLinearScan.isVariableOrRegister(registerHint)) { - Interval from = allocator.getOrCreateInterval((AllocatableValue) registerHint); - Interval to = allocator.getOrCreateInterval((AllocatableValue) targetValue); - - /* hints always point from def to use */ - if (hintAtDef) { - to.setLocationHint(from); - } else { - from.setLocationHint(to); - } - if (Debug.isLogEnabled()) { - Debug.log("operation at opId %d: added hint from interval %d to %d", op.id(), from.operandNumber, to.operandNumber); - } - - return registerHint; - } - return null; - }); - } - } - - /** - * Eliminates moves from register to stack if the stack slot is known to be correct. - * - * @param op - * @param operand - */ - protected void changeSpillDefinitionPos(LIRInstruction op, AllocatableValue operand, Interval interval, int defPos) { - assert interval.isSplitParent() : "can only be called for split parents"; - - switch (interval.spillState()) { - case NoDefinitionFound: - assert interval.spillDefinitionPos() == -1 : "must no be set before"; - interval.setSpillDefinitionPos(defPos); - interval.setSpillState(SpillState.NoSpillStore); - break; - - case NoSpillStore: - assert defPos <= interval.spillDefinitionPos() : "positions are processed in reverse order when intervals are created"; - if (defPos < interval.spillDefinitionPos() - 2) { - // second definition found, so no spill optimization possible for this interval - interval.setSpillState(SpillState.NoOptimization); - } else { - // two consecutive definitions (because of two-operand LIR form) - assert allocator.blockForId(defPos) == allocator.blockForId(interval.spillDefinitionPos()) : "block must be equal"; - } - break; - - case NoOptimization: - // nothing to do - break; - - default: - throw new BailoutException("other states not allowed at this time"); - } - } - - private static boolean optimizeMethodArgument(Value value) { - /* - * Object method arguments that are passed on the stack are currently not optimized because - * this requires that the runtime visits method arguments during stack walking. - */ - return isStackSlot(value) && asStackSlot(value).isInCallerFrame() && value.getKind() != Kind.Object; - } - - /** - * Determines the register priority for an instruction's output/result operand. - */ - protected RegisterPriority registerPriorityOfOutputOperand(LIRInstruction op) { - if (op instanceof ValueMoveOp) { - ValueMoveOp move = (ValueMoveOp) op; - if (optimizeMethodArgument(move.getInput())) { - return RegisterPriority.None; - } - } else if (op instanceof StackStoreOp) { - return RegisterPriority.ShouldHaveRegister; - } - - // all other operands require a register - return RegisterPriority.MustHaveRegister; - } - - /** - * Determines the priority which with an instruction's input operand will be allocated a - * register. - */ - protected static RegisterPriority registerPriorityOfInputOperand(EnumSet<OperandFlag> flags) { - if (flags.contains(OperandFlag.STACK)) { - return RegisterPriority.ShouldHaveRegister; - } - // all other operands require a register - return RegisterPriority.MustHaveRegister; - } - - protected void buildIntervals() { - - try (Indent indent = Debug.logAndIndent("build intervals")) { - InstructionValueConsumer outputConsumer = (op, operand, mode, flags) -> { - if (TraceLinearScan.isVariableOrRegister(operand)) { - addDef((AllocatableValue) operand, op, registerPriorityOfOutputOperand(op), operand.getLIRKind()); - addRegisterHint(op, operand, mode, flags, true); - } - }; - - InstructionValueConsumer tempConsumer = (op, operand, mode, flags) -> { - if (TraceLinearScan.isVariableOrRegister(operand)) { - addTemp((AllocatableValue) operand, op.id(), RegisterPriority.MustHaveRegister, operand.getLIRKind()); - addRegisterHint(op, operand, mode, flags, false); - } - }; - - InstructionValueConsumer aliveConsumer = (op, operand, mode, flags) -> { - if (TraceLinearScan.isVariableOrRegister(operand)) { - RegisterPriority p = registerPriorityOfInputOperand(flags); - int opId = op.id(); - int blockFrom = allocator.getFirstLirInstructionId((allocator.blockForId(opId))); - addUse((AllocatableValue) operand, blockFrom, opId + 1, p, operand.getLIRKind()); - addRegisterHint(op, operand, mode, flags, false); - } - }; - - InstructionValueConsumer inputConsumer = (op, operand, mode, flags) -> { - if (TraceLinearScan.isVariableOrRegister(operand)) { - int opId = op.id(); - int blockFrom = allocator.getFirstLirInstructionId((allocator.blockForId(opId))); - RegisterPriority p = registerPriorityOfInputOperand(flags); - addUse((AllocatableValue) operand, blockFrom, opId, p, operand.getLIRKind()); - addRegisterHint(op, operand, mode, flags, false); - } - }; - - InstructionValueConsumer stateProc = (op, operand, mode, flags) -> { - if (TraceLinearScan.isVariableOrRegister(operand)) { - int opId = op.id(); - int blockFrom = allocator.getFirstLirInstructionId((allocator.blockForId(opId))); - addUse((AllocatableValue) operand, blockFrom, opId + 1, RegisterPriority.None, operand.getLIRKind()); - } - }; - - // create a list with all caller-save registers (cpu, fpu, xmm) - Register[] callerSaveRegs = allocator.getRegisterAllocationConfig().getRegisterConfig().getCallerSaveRegisters(); - - // iterate all blocks in reverse order - for (int i = allocator.blockCount() - 1; i >= 0; i--) { - - AbstractBlockBase<?> block = allocator.blockAt(i); - try (Indent indent2 = Debug.logAndIndent("handle block %d", block.getId())) { - - List<LIRInstruction> instructions = allocator.getLIR().getLIRforBlock(block); - final int blockFrom = allocator.getFirstLirInstructionId(block); - int blockTo = allocator.getLastLirInstructionId(block); - - assert blockFrom == instructions.get(0).id(); - assert blockTo == instructions.get(instructions.size() - 1).id(); - - // Update intervals for operands live at the end of this block; - BitSet live = allocator.getBlockData(block).liveOut; - for (int operandNum = live.nextSetBit(0); operandNum >= 0; operandNum = live.nextSetBit(operandNum + 1)) { - assert live.get(operandNum) : "should not stop here otherwise"; - AllocatableValue operand = allocator.intervalFor(operandNum).operand; - if (Debug.isLogEnabled()) { - Debug.log("live in %d: %s", operandNum, operand); - } - - addUse(operand, blockFrom, blockTo + 2, RegisterPriority.None, LIRKind.Illegal); - - /* - * Add special use positions for loop-end blocks when the interval is used - * anywhere inside this loop. It's possible that the block was part of a - * non-natural loop, so it might have an invalid loop index. - */ - if (block.isLoopEnd() && block.getLoop() != null && isIntervalInLoop(operandNum, block.getLoop().getIndex())) { - allocator.intervalFor(operandNum).addUsePos(blockTo + 1, RegisterPriority.LiveAtLoopEnd); - } - } - - /* - * Iterate all instructions of the block in reverse order. definitions of - * intervals are processed before uses. - */ - for (int j = instructions.size() - 1; j >= 0; j--) { - final LIRInstruction op = instructions.get(j); - final int opId = op.id(); - - try (Indent indent3 = Debug.logAndIndent("handle inst %d: %s", opId, op)) { - - // add a temp range for each register if operation destroys - // caller-save registers - if (op.destroysCallerSavedRegisters()) { - for (Register r : callerSaveRegs) { - if (allocator.attributes(r).isAllocatable()) { - addTemp(r.asValue(), opId, RegisterPriority.None, LIRKind.Illegal); - } - } - if (Debug.isLogEnabled()) { - Debug.log("operation destroys all caller-save registers"); - } - } - - op.visitEachOutput(outputConsumer); - op.visitEachTemp(tempConsumer); - op.visitEachAlive(aliveConsumer); - op.visitEachInput(inputConsumer); - - /* - * Add uses of live locals from interpreter's point of view for proper - * debug information generation. Treat these operands as temp values (if - * the live range is extended to a call site, the value would be in a - * register at the call otherwise). - */ - op.visitEachState(stateProc); - - // special steps for some instructions (especially moves) - handleMethodArguments(op); - - } - - } // end of instruction iteration - } - } // end of block iteration - - /* - * Add the range [0, 1] to all fixed intervals. the register allocator need not handle - * unhandled fixed intervals. - */ - for (Interval interval : allocator.intervals()) { - if (interval != null && isRegister(interval.operand)) { - interval.addRange(0, 1); - } - } - } - } - - /** - * Returns a value for a interval definition, which can be used for re-materialization. - * - * @param op An instruction which defines a value - * @param operand The destination operand of the instruction - * @param interval The interval for this defined value. - * @return Returns the value which is moved to the instruction and which can be reused at all - * reload-locations in case the interval of this instruction is spilled. Currently this - * can only be a {@link JavaConstant}. - */ - protected static JavaConstant getMaterializedValue(LIRInstruction op, Value operand, Interval interval) { - if (op instanceof LoadConstantOp) { - LoadConstantOp move = (LoadConstantOp) op; - if (move.getConstant() instanceof JavaConstant) { - /* - * Check if the interval has any uses which would accept an stack location (priority - * == ShouldHaveRegister). Rematerialization of such intervals can result in a - * degradation, because rematerialization always inserts a constant load, even if - * the value is not needed in a register. - */ - Interval.UsePosList usePosList = interval.usePosList(); - int numUsePos = usePosList.size(); - for (int useIdx = 0; useIdx < numUsePos; useIdx++) { - Interval.RegisterPriority priority = usePosList.registerPriority(useIdx); - if (priority == Interval.RegisterPriority.ShouldHaveRegister) { - return null; - } - } - return (JavaConstant) move.getConstant(); - } - } - return null; - } -}
--- a/graal/com.oracle.graal.lir/src/com/oracle/graal/lir/alloc/trace/TraceLinearScan.java Mon Aug 31 13:33:08 2015 +0200 +++ b/graal/com.oracle.graal.lir/src/com/oracle/graal/lir/alloc/trace/TraceLinearScan.java Mon Aug 31 15:10:29 2015 +0200 @@ -652,7 +652,7 @@ } } - protected LinearScanLifetimeAnalysisPhase createLifetimeAnalysisPhase() { + protected TraceLinearScanLifetimeAnalysisPhase createLifetimeAnalysisPhase() { if (Options.TraceRAsimpleLifetimeAnalysis.getValue()) { return new TraceSimpleLifetimeAnalysisPhase(this, traceBuilderResult); }
--- a/graal/com.oracle.graal.lir/src/com/oracle/graal/lir/alloc/trace/TraceLinearScanLifetimeAnalysisPhase.java Mon Aug 31 13:33:08 2015 +0200 +++ b/graal/com.oracle.graal.lir/src/com/oracle/graal/lir/alloc/trace/TraceLinearScanLifetimeAnalysisPhase.java Mon Aug 31 15:10:29 2015 +0200 @@ -25,6 +25,7 @@ import static com.oracle.graal.compiler.common.GraalOptions.*; import static com.oracle.graal.lir.LIRValueUtil.*; import static com.oracle.graal.lir.alloc.trace.TraceRegisterAllocationPhase.Options.*; +import static com.oracle.graal.lir.debug.LIRGenerationDebugContext.*; import static jdk.internal.jvmci.code.ValueUtil.*; import java.util.*; @@ -33,27 +34,53 @@ import jdk.internal.jvmci.common.*; import jdk.internal.jvmci.meta.*; +import com.oracle.graal.compiler.common.alloc.*; import com.oracle.graal.compiler.common.alloc.TraceBuilder.TraceBuilderResult; import com.oracle.graal.compiler.common.cfg.*; +import com.oracle.graal.compiler.common.util.*; import com.oracle.graal.debug.*; +import com.oracle.graal.debug.Debug.Scope; import com.oracle.graal.lir.*; +import com.oracle.graal.lir.LIRInstruction.OperandFlag; +import com.oracle.graal.lir.LIRInstruction.OperandMode; import com.oracle.graal.lir.StandardOp.BlockEndOp; import com.oracle.graal.lir.StandardOp.LabelOp; +import com.oracle.graal.lir.StandardOp.LoadConstantOp; import com.oracle.graal.lir.StandardOp.MoveOp; +import com.oracle.graal.lir.StandardOp.StackStoreOp; +import com.oracle.graal.lir.StandardOp.ValueMoveOp; import com.oracle.graal.lir.alloc.trace.Interval.RegisterPriority; import com.oracle.graal.lir.alloc.trace.Interval.SpillState; import com.oracle.graal.lir.alloc.trace.TraceLinearScan.BlockData; +import com.oracle.graal.lir.gen.*; +import com.oracle.graal.lir.gen.LIRGeneratorTool.SpillMoveFactory; +import com.oracle.graal.lir.phases.*; import com.oracle.graal.lir.ssi.*; -public class TraceLinearScanLifetimeAnalysisPhase extends LinearScanLifetimeAnalysisPhase { +public class TraceLinearScanLifetimeAnalysisPhase extends AllocationPhase { + protected final TraceLinearScan allocator; private final TraceBuilderResult<?> traceBuilderResult; - public TraceLinearScanLifetimeAnalysisPhase(TraceLinearScan linearScan, TraceBuilderResult<?> traceBuilderResult) { - super(linearScan); + /** + * @param linearScan + * @param traceBuilderResult + */ + protected TraceLinearScanLifetimeAnalysisPhase(TraceLinearScan linearScan, TraceBuilderResult<?> traceBuilderResult) { + allocator = linearScan; this.traceBuilderResult = traceBuilderResult; } + @Override + protected <B extends AbstractBlockBase<B>> void run(TargetDescription target, LIRGenerationResult lirGenRes, List<B> codeEmittingOrder, List<B> linearScanOrder, SpillMoveFactory spillMoveFactory, + RegisterAllocationConfig registerAllocationConfig) { + numberInstructions(); + allocator.printLir("Before register allocation", true); + computeLocalLiveSets(); + computeGlobalLiveSets(); + buildIntervals(); + } + private boolean sameTrace(AbstractBlockBase<?> a, AbstractBlockBase<?> b) { return traceBuilderResult.getTraceForBlock(b) == traceBuilderResult.getTraceForBlock(a); } @@ -76,7 +103,536 @@ } } - @Override + /** + * Bit set for each variable that is contained in each loop. + */ + private BitMap2D intervalInLoop; + + boolean isIntervalInLoop(int interval, int loop) { + return intervalInLoop.at(interval, loop); + } + + /** + * Numbers all instructions in all blocks. The numbering follows the + * {@linkplain ComputeBlockOrder linear scan order}. + */ + protected void numberInstructions() { + + allocator.initIntervals(); + + ValueConsumer setVariableConsumer = (value, mode, flags) -> { + if (isVariable(value)) { + allocator.getOrCreateInterval(asVariable(value)); + } + }; + + // Assign IDs to LIR nodes and build a mapping, lirOps, from ID to LIRInstruction node. + int numInstructions = 0; + for (AbstractBlockBase<?> block : allocator.sortedBlocks()) { + numInstructions += allocator.getLIR().getLIRforBlock(block).size(); + } + + // initialize with correct length + allocator.initOpIdMaps(numInstructions); + + int opId = 0; + int index = 0; + for (AbstractBlockBase<?> block : allocator.sortedBlocks()) { + allocator.initBlockData(block); + + List<LIRInstruction> instructions = allocator.getLIR().getLIRforBlock(block); + + int numInst = instructions.size(); + for (int j = 0; j < numInst; j++) { + LIRInstruction op = instructions.get(j); + op.setId(opId); + + allocator.putOpIdMaps(index, op, block); + assert allocator.instructionForId(opId) == op : "must match"; + + op.visitEachTemp(setVariableConsumer); + op.visitEachOutput(setVariableConsumer); + + index++; + opId += 2; // numbering of lirOps by two + } + } + assert index == numInstructions : "must match"; + assert (index << 1) == opId : "must match: " + (index << 1); + } + + /** + * Computes local live sets (i.e. {@link BlockData#liveGen} and {@link BlockData#liveKill}) + * separately for each block. + */ + void computeLocalLiveSets() { + int liveSize = allocator.liveSetSize(); + + intervalInLoop = new BitMap2D(allocator.operandSize(), allocator.numLoops()); + + // iterate all blocks + for (final AbstractBlockBase<?> block : allocator.sortedBlocks()) { + try (Indent indent = Debug.logAndIndent("compute local live sets for block %s", block)) { + + final BitSet liveGen = new BitSet(liveSize); + final BitSet liveKill = new BitSet(liveSize); + + List<LIRInstruction> instructions = allocator.getLIR().getLIRforBlock(block); + int numInst = instructions.size(); + + ValueConsumer useConsumer = (operand, mode, flags) -> { + if (isVariable(operand)) { + int operandNum = allocator.operandNumber(operand); + if (!liveKill.get(operandNum)) { + liveGen.set(operandNum); + if (Debug.isLogEnabled()) { + Debug.log("liveGen for operand %d(%s)", operandNum, operand); + } + } + if (block.getLoop() != null) { + intervalInLoop.setBit(operandNum, block.getLoop().getIndex()); + } + } + + if (DetailedAsserts.getValue()) { + verifyInput(block, liveKill, operand); + } + }; + ValueConsumer stateConsumer = (operand, mode, flags) -> { + if (TraceLinearScan.isVariableOrRegister(operand)) { + int operandNum = allocator.operandNumber(operand); + if (!liveKill.get(operandNum)) { + liveGen.set(operandNum); + if (Debug.isLogEnabled()) { + Debug.log("liveGen in state for operand %d(%s)", operandNum, operand); + } + } + } + }; + ValueConsumer defConsumer = (operand, mode, flags) -> { + if (isVariable(operand)) { + int varNum = allocator.operandNumber(operand); + liveKill.set(varNum); + if (Debug.isLogEnabled()) { + Debug.log("liveKill for operand %d(%s)", varNum, operand); + } + if (block.getLoop() != null) { + intervalInLoop.setBit(varNum, block.getLoop().getIndex()); + } + } + + if (DetailedAsserts.getValue()) { + /* + * Fixed intervals are never live at block boundaries, so they need not be + * processed in live sets. Process them only in debug mode so that this can + * be checked + */ + verifyTemp(liveKill, operand); + } + }; + + // iterate all instructions of the block + for (int j = 0; j < numInst; j++) { + final LIRInstruction op = instructions.get(j); + + try (Indent indent2 = Debug.logAndIndent("handle op %d: %s", op.id(), op)) { + op.visitEachInput(useConsumer); + op.visitEachAlive(useConsumer); + /* + * Add uses of live locals from interpreter's point of view for proper debug + * information generation. + */ + op.visitEachState(stateConsumer); + op.visitEachTemp(defConsumer); + op.visitEachOutput(defConsumer); + } + } // end of instruction iteration + + BlockData blockSets = allocator.getBlockData(block); + blockSets.liveGen = liveGen; + blockSets.liveKill = liveKill; + blockSets.liveIn = new BitSet(liveSize); + blockSets.liveOut = new BitSet(liveSize); + + if (Debug.isLogEnabled()) { + Debug.log("liveGen B%d %s", block.getId(), blockSets.liveGen); + Debug.log("liveKill B%d %s", block.getId(), blockSets.liveKill); + } + + } + } // end of block iteration + } + + private void verifyTemp(BitSet liveKill, Value operand) { + /* + * Fixed intervals are never live at block boundaries, so they need not be processed in live + * sets. Process them only in debug mode so that this can be checked + */ + if (isRegister(operand)) { + if (allocator.isProcessed(operand)) { + liveKill.set(allocator.operandNumber(operand)); + } + } + } + + private void verifyInput(AbstractBlockBase<?> block, BitSet liveKill, Value operand) { + /* + * Fixed intervals are never live at block boundaries, so they need not be processed in live + * sets. This is checked by these assertions to be sure about it. The entry block may have + * incoming values in registers, which is ok. + */ + if (isRegister(operand) && block != allocator.getLIR().getControlFlowGraph().getStartBlock()) { + if (allocator.isProcessed(operand)) { + assert liveKill.get(allocator.operandNumber(operand)) : "using fixed register that is not defined in this block"; + } + } + } + + /** + * Performs a backward dataflow analysis to compute global live sets (i.e. + * {@link BlockData#liveIn} and {@link BlockData#liveOut}) for each block. + */ + protected void computeGlobalLiveSets() { + try (Indent indent = Debug.logAndIndent("compute global live sets")) { + int numBlocks = allocator.blockCount(); + boolean changeOccurred; + boolean changeOccurredInBlock; + int iterationCount = 0; + BitSet liveOut = new BitSet(allocator.liveSetSize()); // scratch set for calculations + + /* + * Perform a backward dataflow analysis to compute liveOut and liveIn for each block. + * The loop is executed until a fixpoint is reached (no changes in an iteration). + */ + do { + changeOccurred = false; + + try (Indent indent2 = Debug.logAndIndent("new iteration %d", iterationCount)) { + + // iterate all blocks in reverse order + for (int i = numBlocks - 1; i >= 0; i--) { + AbstractBlockBase<?> block = allocator.blockAt(i); + BlockData blockSets = allocator.getBlockData(block); + + changeOccurredInBlock = false; + + /* liveOut(block) is the union of liveIn(sux), for successors sux of block. */ + int n = block.getSuccessorCount(); + if (n > 0) { + liveOut.clear(); + // block has successors + if (n > 0) { + for (AbstractBlockBase<?> successor : block.getSuccessors()) { + if (allocator.sortedBlocks().contains(successor)) { + liveOut.or(allocator.getBlockData(successor).liveIn); + } + } + } + + if (!blockSets.liveOut.equals(liveOut)) { + /* + * A change occurred. Swap the old and new live out sets to avoid + * copying. + */ + BitSet temp = blockSets.liveOut; + blockSets.liveOut = liveOut; + liveOut = temp; + + changeOccurred = true; + changeOccurredInBlock = true; + } + } + + if (iterationCount == 0 || changeOccurredInBlock) { + /* + * liveIn(block) is the union of liveGen(block) with (liveOut(block) & + * !liveKill(block)). + * + * Note: liveIn has to be computed only in first iteration or if liveOut + * has changed! + */ + BitSet liveIn = blockSets.liveIn; + liveIn.clear(); + liveIn.or(blockSets.liveOut); + liveIn.andNot(blockSets.liveKill); + liveIn.or(blockSets.liveGen); + + if (Debug.isLogEnabled()) { + Debug.log("block %d: livein = %s, liveout = %s", block.getId(), liveIn, blockSets.liveOut); + } + } + } + iterationCount++; + + if (changeOccurred && iterationCount > 50) { + throw new BailoutException("too many iterations in computeGlobalLiveSets"); + } + } + } while (changeOccurred); + + if (DetailedAsserts.getValue()) { + verifyLiveness(); + } + + // check that the liveIn set of the first block is empty + AbstractBlockBase<?> startBlock = allocator.blockAt(0); + if (allocator.getBlockData(startBlock).liveIn.cardinality() != 0) { + if (DetailedAsserts.getValue()) { + reportFailure(numBlocks); + } + // bailout if this occurs in product mode. + throw new JVMCIError("liveIn set of first block must be empty: " + allocator.getBlockData(startBlock).liveIn); + } + } + } + + protected void reportFailure(int numBlocks) { + try (Scope s = Debug.forceLog()) { + try (Indent indent = Debug.logAndIndent("report failure")) { + + BitSet startBlockLiveIn = allocator.getBlockData(allocator.getLIR().getControlFlowGraph().getStartBlock()).liveIn; + try (Indent indent2 = Debug.logAndIndent("Error: liveIn set of first block must be empty (when this fails, variables are used before they are defined):")) { + for (int operandNum = startBlockLiveIn.nextSetBit(0); operandNum >= 0; operandNum = startBlockLiveIn.nextSetBit(operandNum + 1)) { + Interval interval = allocator.intervalFor(operandNum); + if (interval != null) { + Value operand = interval.operand; + Debug.log("var %d; operand=%s; node=%s", operandNum, operand, getSourceForOperandFromDebugContext(operand)); + } else { + Debug.log("var %d; missing operand", operandNum); + } + } + } + + // print some additional information to simplify debugging + for (int operandNum = startBlockLiveIn.nextSetBit(0); operandNum >= 0; operandNum = startBlockLiveIn.nextSetBit(operandNum + 1)) { + Interval interval = allocator.intervalFor(operandNum); + Value operand = null; + Object valueForOperandFromDebugContext = null; + if (interval != null) { + operand = interval.operand; + valueForOperandFromDebugContext = getSourceForOperandFromDebugContext(operand); + } + try (Indent indent2 = Debug.logAndIndent("---- Detailed information for var %d; operand=%s; node=%s ----", operandNum, operand, valueForOperandFromDebugContext)) { + + Deque<AbstractBlockBase<?>> definedIn = new ArrayDeque<>(); + HashSet<AbstractBlockBase<?>> usedIn = new HashSet<>(); + for (AbstractBlockBase<?> block : allocator.sortedBlocks()) { + if (allocator.getBlockData(block).liveGen.get(operandNum)) { + usedIn.add(block); + try (Indent indent3 = Debug.logAndIndent("used in block B%d", block.getId())) { + for (LIRInstruction ins : allocator.getLIR().getLIRforBlock(block)) { + try (Indent indent4 = Debug.logAndIndent("%d: %s", ins.id(), ins)) { + ins.forEachState((liveStateOperand, mode, flags) -> { + Debug.log("operand=%s", liveStateOperand); + return liveStateOperand; + }); + } + } + } + } + if (allocator.getBlockData(block).liveKill.get(operandNum)) { + definedIn.add(block); + try (Indent indent3 = Debug.logAndIndent("defined in block B%d", block.getId())) { + for (LIRInstruction ins : allocator.getLIR().getLIRforBlock(block)) { + Debug.log("%d: %s", ins.id(), ins); + } + } + } + } + + int[] hitCount = new int[numBlocks]; + + while (!definedIn.isEmpty()) { + AbstractBlockBase<?> block = definedIn.removeFirst(); + usedIn.remove(block); + for (AbstractBlockBase<?> successor : block.getSuccessors()) { + if (successor.isLoopHeader()) { + if (!block.isLoopEnd()) { + definedIn.add(successor); + } + } else { + if (++hitCount[successor.getId()] == successor.getPredecessorCount()) { + definedIn.add(successor); + } + } + } + } + try (Indent indent3 = Debug.logAndIndent("**** offending usages are in: ")) { + for (AbstractBlockBase<?> block : usedIn) { + Debug.log("B%d", block.getId()); + } + } + } + } + } + } catch (Throwable e) { + throw Debug.handle(e); + } + } + + protected void verifyLiveness() { + /* + * Check that fixed intervals are not live at block boundaries (live set must be empty at + * fixed intervals). + */ + for (AbstractBlockBase<?> block : allocator.sortedBlocks()) { + for (int j = 0; j <= allocator.maxRegisterNumber(); j++) { + assert !allocator.getBlockData(block).liveIn.get(j) : "liveIn set of fixed register must be empty"; + assert !allocator.getBlockData(block).liveOut.get(j) : "liveOut set of fixed register must be empty"; + assert !allocator.getBlockData(block).liveGen.get(j) : "liveGen set of fixed register must be empty"; + } + } + } + + protected void addUse(AllocatableValue operand, int from, int to, RegisterPriority registerPriority, LIRKind kind) { + if (!allocator.isProcessed(operand)) { + return; + } + + Interval interval = allocator.getOrCreateInterval(operand); + if (!kind.equals(LIRKind.Illegal)) { + interval.setKind(kind); + } + + interval.addRange(from, to); + + // Register use position at even instruction id. + interval.addUsePos(to & ~1, registerPriority); + + if (Debug.isLogEnabled()) { + Debug.log("add use: %s, from %d to %d (%s)", interval, from, to, registerPriority.name()); + } + } + + protected void addTemp(AllocatableValue operand, int tempPos, RegisterPriority registerPriority, LIRKind kind) { + if (!allocator.isProcessed(operand)) { + return; + } + + Interval interval = allocator.getOrCreateInterval(operand); + if (!kind.equals(LIRKind.Illegal)) { + interval.setKind(kind); + } + + interval.addRange(tempPos, tempPos + 1); + interval.addUsePos(tempPos, registerPriority); + interval.addMaterializationValue(null); + + if (Debug.isLogEnabled()) { + Debug.log("add temp: %s tempPos %d (%s)", interval, tempPos, RegisterPriority.MustHaveRegister.name()); + } + } + + protected void addDef(AllocatableValue operand, LIRInstruction op, RegisterPriority registerPriority, LIRKind kind) { + if (!allocator.isProcessed(operand)) { + return; + } + int defPos = op.id(); + + Interval interval = allocator.getOrCreateInterval(operand); + if (!kind.equals(LIRKind.Illegal)) { + interval.setKind(kind); + } + + Range r = interval.first(); + if (r.from <= defPos) { + /* + * Update the starting point (when a range is first created for a use, its start is the + * beginning of the current block until a def is encountered). + */ + r.from = defPos; + interval.addUsePos(defPos, registerPriority); + + } else { + /* + * Dead value - make vacuous interval also add register priority for dead intervals + */ + interval.addRange(defPos, defPos + 1); + interval.addUsePos(defPos, registerPriority); + if (Debug.isLogEnabled()) { + Debug.log("Warning: def of operand %s at %d occurs without use", operand, defPos); + } + } + + changeSpillDefinitionPos(op, operand, interval, defPos); + if (registerPriority == RegisterPriority.None && interval.spillState().ordinal() <= SpillState.StartInMemory.ordinal() && isStackSlot(operand)) { + // detection of method-parameters and roundfp-results + interval.setSpillState(SpillState.StartInMemory); + } + interval.addMaterializationValue(getMaterializedValue(op, operand, interval)); + + if (Debug.isLogEnabled()) { + Debug.log("add def: %s defPos %d (%s)", interval, defPos, registerPriority.name()); + } + } + + /** + * Optimizes moves related to incoming stack based arguments. The interval for the destination + * of such moves is assigned the stack slot (which is in the caller's frame) as its spill slot. + */ + protected void handleMethodArguments(LIRInstruction op) { + if (op instanceof MoveOp) { + // do not optimize method arguments + return; + } + if (op instanceof ValueMoveOp) { + ValueMoveOp move = (ValueMoveOp) op; + if (optimizeMethodArgument(move.getInput())) { + StackSlot slot = asStackSlot(move.getInput()); + if (DetailedAsserts.getValue()) { + assert op.id() > 0 : "invalid id"; + assert allocator.blockForId(op.id()).getPredecessorCount() == 0 : "move from stack must be in first block"; + assert isVariable(move.getResult()) : "result of move must be a variable"; + + if (Debug.isLogEnabled()) { + Debug.log("found move from stack slot %s to %s", slot, move.getResult()); + } + } + + Interval interval = allocator.intervalFor(move.getResult()); + interval.setSpillSlot(slot); + interval.assignLocation(slot); + } + } else if (op instanceof StackStoreOp) { + StackStoreOp store = (StackStoreOp) op; + StackSlot slot = asStackSlot(store.getStackSlot()); + Interval interval = allocator.intervalFor(store.getResult()); + interval.setSpillSlot(slot); + interval.setSpillState(SpillState.StartInMemory); + } + } + + protected void addRegisterHint(final LIRInstruction op, final Value targetValue, OperandMode mode, EnumSet<OperandFlag> flags, final boolean hintAtDef) { + if (flags.contains(OperandFlag.HINT) && TraceLinearScan.isVariableOrRegister(targetValue)) { + + op.forEachRegisterHint(targetValue, mode, (registerHint, valueMode, valueFlags) -> { + if (TraceLinearScan.isVariableOrRegister(registerHint)) { + Interval from = allocator.getOrCreateInterval((AllocatableValue) registerHint); + Interval to = allocator.getOrCreateInterval((AllocatableValue) targetValue); + + /* hints always point from def to use */ + if (hintAtDef) { + to.setLocationHint(from); + } else { + from.setLocationHint(to); + } + if (Debug.isLogEnabled()) { + Debug.log("operation at opId %d: added hint from interval %d to %d", op.id(), from.operandNumber, to.operandNumber); + } + + return registerHint; + } + return null; + }); + } + } + + /** + * Eliminates moves from register to stack if the stack slot is known to be correct. + * + * @param op + * @param operand + */ protected void changeSpillDefinitionPos(LIRInstruction op, AllocatableValue operand, Interval interval, int defPos) { assert interval.isSplitParent() : "can only be called for split parents"; @@ -110,9 +666,184 @@ } } - @Override + private static boolean optimizeMethodArgument(Value value) { + /* + * Object method arguments that are passed on the stack are currently not optimized because + * this requires that the runtime visits method arguments during stack walking. + */ + return isStackSlot(value) && asStackSlot(value).isInCallerFrame() && value.getKind() != Kind.Object; + } + + /** + * Determines the register priority for an instruction's output/result operand. + */ + protected RegisterPriority registerPriorityOfOutputOperand(LIRInstruction op) { + if (op instanceof LabelOp) { + // skip method header + return RegisterPriority.None; + } + if (op instanceof ValueMoveOp) { + ValueMoveOp move = (ValueMoveOp) op; + if (optimizeMethodArgument(move.getInput())) { + return RegisterPriority.None; + } + } else if (op instanceof StackStoreOp) { + return RegisterPriority.ShouldHaveRegister; + } + + // all other operands require a register + return RegisterPriority.MustHaveRegister; + } + + /** + * Determines the priority which with an instruction's input operand will be allocated a + * register. + */ + protected static RegisterPriority registerPriorityOfInputOperand(EnumSet<OperandFlag> flags) { + if (flags.contains(OperandFlag.STACK)) { + return RegisterPriority.ShouldHaveRegister; + } + // all other operands require a register + return RegisterPriority.MustHaveRegister; + } + protected void buildIntervals() { - super.buildIntervals(); + + try (Indent indent = Debug.logAndIndent("build intervals")) { + InstructionValueConsumer outputConsumer = (op, operand, mode, flags) -> { + if (TraceLinearScan.isVariableOrRegister(operand)) { + addDef((AllocatableValue) operand, op, registerPriorityOfOutputOperand(op), operand.getLIRKind()); + addRegisterHint(op, operand, mode, flags, true); + } + }; + + InstructionValueConsumer tempConsumer = (op, operand, mode, flags) -> { + if (TraceLinearScan.isVariableOrRegister(operand)) { + addTemp((AllocatableValue) operand, op.id(), RegisterPriority.MustHaveRegister, operand.getLIRKind()); + addRegisterHint(op, operand, mode, flags, false); + } + }; + + InstructionValueConsumer aliveConsumer = (op, operand, mode, flags) -> { + if (TraceLinearScan.isVariableOrRegister(operand)) { + RegisterPriority p = registerPriorityOfInputOperand(flags); + int opId = op.id(); + int blockFrom = allocator.getFirstLirInstructionId((allocator.blockForId(opId))); + addUse((AllocatableValue) operand, blockFrom, opId + 1, p, operand.getLIRKind()); + addRegisterHint(op, operand, mode, flags, false); + } + }; + + InstructionValueConsumer inputConsumer = (op, operand, mode, flags) -> { + if (TraceLinearScan.isVariableOrRegister(operand)) { + int opId = op.id(); + int blockFrom = allocator.getFirstLirInstructionId((allocator.blockForId(opId))); + RegisterPriority p = registerPriorityOfInputOperand(flags); + addUse((AllocatableValue) operand, blockFrom, opId, p, operand.getLIRKind()); + addRegisterHint(op, operand, mode, flags, false); + } + }; + + InstructionValueConsumer stateProc = (op, operand, mode, flags) -> { + if (TraceLinearScan.isVariableOrRegister(operand)) { + int opId = op.id(); + int blockFrom = allocator.getFirstLirInstructionId((allocator.blockForId(opId))); + addUse((AllocatableValue) operand, blockFrom, opId + 1, RegisterPriority.None, operand.getLIRKind()); + } + }; + + // create a list with all caller-save registers (cpu, fpu, xmm) + Register[] callerSaveRegs = allocator.getRegisterAllocationConfig().getRegisterConfig().getCallerSaveRegisters(); + + // iterate all blocks in reverse order + for (int i = allocator.blockCount() - 1; i >= 0; i--) { + + AbstractBlockBase<?> block = allocator.blockAt(i); + try (Indent indent2 = Debug.logAndIndent("handle block %d", block.getId())) { + + List<LIRInstruction> instructions = allocator.getLIR().getLIRforBlock(block); + final int blockFrom = allocator.getFirstLirInstructionId(block); + int blockTo = allocator.getLastLirInstructionId(block); + + assert blockFrom == instructions.get(0).id(); + assert blockTo == instructions.get(instructions.size() - 1).id(); + + // Update intervals for operands live at the end of this block; + BitSet live = allocator.getBlockData(block).liveOut; + for (int operandNum = live.nextSetBit(0); operandNum >= 0; operandNum = live.nextSetBit(operandNum + 1)) { + assert live.get(operandNum) : "should not stop here otherwise"; + AllocatableValue operand = allocator.intervalFor(operandNum).operand; + if (Debug.isLogEnabled()) { + Debug.log("live in %d: %s", operandNum, operand); + } + + addUse(operand, blockFrom, blockTo + 2, RegisterPriority.None, LIRKind.Illegal); + + /* + * Add special use positions for loop-end blocks when the interval is used + * anywhere inside this loop. It's possible that the block was part of a + * non-natural loop, so it might have an invalid loop index. + */ + if (block.isLoopEnd() && block.getLoop() != null && isIntervalInLoop(operandNum, block.getLoop().getIndex())) { + allocator.intervalFor(operandNum).addUsePos(blockTo + 1, RegisterPriority.LiveAtLoopEnd); + } + } + + /* + * Iterate all instructions of the block in reverse order. definitions of + * intervals are processed before uses. + */ + for (int j = instructions.size() - 1; j >= 0; j--) { + final LIRInstruction op = instructions.get(j); + final int opId = op.id(); + + try (Indent indent3 = Debug.logAndIndent("handle inst %d: %s", opId, op)) { + + // add a temp range for each register if operation destroys + // caller-save registers + if (op.destroysCallerSavedRegisters()) { + for (Register r : callerSaveRegs) { + if (allocator.attributes(r).isAllocatable()) { + addTemp(r.asValue(), opId, RegisterPriority.None, LIRKind.Illegal); + } + } + if (Debug.isLogEnabled()) { + Debug.log("operation destroys all caller-save registers"); + } + } + + op.visitEachOutput(outputConsumer); + op.visitEachTemp(tempConsumer); + op.visitEachAlive(aliveConsumer); + op.visitEachInput(inputConsumer); + + /* + * Add uses of live locals from interpreter's point of view for proper + * debug information generation. Treat these operands as temp values (if + * the live range is extended to a call site, the value would be in a + * register at the call otherwise). + */ + op.visitEachState(stateProc); + + // special steps for some instructions (especially moves) + handleMethodArguments(op); + + } + + } // end of instruction iteration + } + } // end of block iteration + + /* + * Add the range [0, 1] to all fixed intervals. the register allocator need not handle + * unhandled fixed intervals. + */ + for (Interval interval : allocator.intervals()) { + if (interval != null && isRegister(interval.operand)) { + interval.addRange(0, 1); + } + } + } postBuildIntervals(); } @@ -177,120 +908,37 @@ } } - @Override - protected RegisterPriority registerPriorityOfOutputOperand(LIRInstruction op) { - if (op instanceof LabelOp) { - // skip method header - return RegisterPriority.None; - } - return super.registerPriorityOfOutputOperand(op); - } - - @Override - protected void handleMethodArguments(LIRInstruction op) { - if (op instanceof MoveOp) { - // do not optimize method arguments - return; - } - super.handleMethodArguments(op); - } - /** - * Performs a backward dataflow analysis to compute global live sets (i.e. - * {@link BlockData#liveIn} and {@link BlockData#liveOut}) for each block. + * Returns a value for a interval definition, which can be used for re-materialization. + * + * @param op An instruction which defines a value + * @param operand The destination operand of the instruction + * @param interval The interval for this defined value. + * @return Returns the value which is moved to the instruction and which can be reused at all + * reload-locations in case the interval of this instruction is spilled. Currently this + * can only be a {@link JavaConstant}. */ - @Override - protected void computeGlobalLiveSets() { - try (Indent indent = Debug.logAndIndent("compute global live sets")) { - int numBlocks = allocator.blockCount(); - boolean changeOccurred; - boolean changeOccurredInBlock; - int iterationCount = 0; - BitSet liveOut = new BitSet(allocator.liveSetSize()); // scratch set for calculations - - /* - * Perform a backward dataflow analysis to compute liveOut and liveIn for each block. - * The loop is executed until a fixpoint is reached (no changes in an iteration). - */ - do { - changeOccurred = false; - - try (Indent indent2 = Debug.logAndIndent("new iteration %d", iterationCount)) { - - // iterate all blocks in reverse order - for (int i = numBlocks - 1; i >= 0; i--) { - AbstractBlockBase<?> block = allocator.blockAt(i); - BlockData blockSets = allocator.getBlockData(block); - - changeOccurredInBlock = false; - - /* liveOut(block) is the union of liveIn(sux), for successors sux of block. */ - int n = block.getSuccessorCount(); - if (n > 0) { - liveOut.clear(); - // block has successors - if (n > 0) { - for (AbstractBlockBase<?> successor : block.getSuccessors()) { - if (allocator.sortedBlocks().contains(successor)) { - liveOut.or(allocator.getBlockData(successor).liveIn); - } - } - } - - if (!blockSets.liveOut.equals(liveOut)) { - /* - * A change occurred. Swap the old and new live out sets to avoid - * copying. - */ - BitSet temp = blockSets.liveOut; - blockSets.liveOut = liveOut; - liveOut = temp; - - changeOccurred = true; - changeOccurredInBlock = true; - } - } - - if (iterationCount == 0 || changeOccurredInBlock) { - /* - * liveIn(block) is the union of liveGen(block) with (liveOut(block) & - * !liveKill(block)). - * - * Note: liveIn has to be computed only in first iteration or if liveOut - * has changed! - */ - BitSet liveIn = blockSets.liveIn; - liveIn.clear(); - liveIn.or(blockSets.liveOut); - liveIn.andNot(blockSets.liveKill); - liveIn.or(blockSets.liveGen); - - if (Debug.isLogEnabled()) { - Debug.log("block %d: livein = %s, liveout = %s", block.getId(), liveIn, blockSets.liveOut); - } - } - } - iterationCount++; - - if (changeOccurred && iterationCount > 50) { - throw new BailoutException("too many iterations in computeGlobalLiveSets"); + protected static JavaConstant getMaterializedValue(LIRInstruction op, Value operand, Interval interval) { + if (op instanceof LoadConstantOp) { + LoadConstantOp move = (LoadConstantOp) op; + if (move.getConstant() instanceof JavaConstant) { + /* + * Check if the interval has any uses which would accept an stack location (priority + * == ShouldHaveRegister). Rematerialization of such intervals can result in a + * degradation, because rematerialization always inserts a constant load, even if + * the value is not needed in a register. + */ + Interval.UsePosList usePosList = interval.usePosList(); + int numUsePos = usePosList.size(); + for (int useIdx = 0; useIdx < numUsePos; useIdx++) { + Interval.RegisterPriority priority = usePosList.registerPriority(useIdx); + if (priority == Interval.RegisterPriority.ShouldHaveRegister) { + return null; } } - } while (changeOccurred); - - if (DetailedAsserts.getValue()) { - verifyLiveness(); - } - - // check that the liveIn set of the first block is empty - AbstractBlockBase<?> startBlock = allocator.blockAt(0); - if (allocator.getBlockData(startBlock).liveIn.cardinality() != 0) { - if (DetailedAsserts.getValue()) { - reportFailure(numBlocks); - } - // bailout if this occurs in product mode. - throw new JVMCIError("liveIn set of first block must be empty: " + allocator.getBlockData(startBlock).liveIn); + return (JavaConstant) move.getConstant(); } } + return null; } }