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view graal/com.oracle.graal.lir/src/com/oracle/graal/lir/alloc/lsra/LinearScan.java @ 21561:ce2113326bc8
Merge.
author | Doug Simon <doug.simon@oracle.com> |
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date | Thu, 28 May 2015 17:13:22 +0200 |
parents | 48c1ebd24120 47c5e0903d06 |
children | 6c5327245831 |
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/* * Copyright (c) 2009, 2014, 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.lsra; import static com.oracle.graal.compiler.common.GraalOptions.*; import static com.oracle.graal.lir.LIRValueUtil.*; import static com.oracle.jvmci.code.CodeUtil.*; import static com.oracle.jvmci.code.ValueUtil.*; import java.util.*; import com.oracle.graal.compiler.common.alloc.*; import com.oracle.graal.compiler.common.cfg.*; import com.oracle.graal.lir.*; import com.oracle.graal.lir.LIRInstruction.OperandFlag; import com.oracle.graal.lir.LIRInstruction.OperandMode; import com.oracle.graal.lir.alloc.lsra.Interval.RegisterBinding; import com.oracle.graal.lir.framemap.*; import com.oracle.graal.lir.gen.*; import com.oracle.graal.lir.gen.LIRGeneratorTool.SpillMoveFactory; import com.oracle.graal.lir.phases.AllocationPhase.AllocationContext; import com.oracle.jvmci.code.*; import com.oracle.jvmci.common.*; import com.oracle.jvmci.debug.*; import com.oracle.jvmci.debug.Debug.Scope; import com.oracle.jvmci.meta.*; import com.oracle.jvmci.options.*; /** * An implementation of the linear scan register allocator algorithm described in <a * href="http://doi.acm.org/10.1145/1064979.1064998" * >"Optimized Interval Splitting in a Linear Scan Register Allocator"</a> by Christian Wimmer and * Hanspeter Moessenboeck. */ class LinearScan { final LIRGenerationResult res; final LIR ir; final FrameMapBuilder frameMapBuilder; final RegisterAttributes[] registerAttributes; final Register[] registers; final RegisterAllocationConfig regAllocConfig; private final SpillMoveFactory moveFactory; final boolean callKillsRegisters; public static final int DOMINATOR_SPILL_MOVE_ID = -2; static final int SPLIT_INTERVALS_CAPACITY_RIGHT_SHIFT = 1; public static class Options { // @formatter:off @Option(help = "Enable spill position optimization", type = OptionType.Debug) public static final OptionValue<Boolean> LSRAOptimizeSpillPosition = new OptionValue<>(true); // @formatter:on } public static class BlockData { /** * Bit map specifying which operands are live upon entry to this block. These are values * used in this block or any of its successors where such value are not defined in this * block. The bit index of an operand is its {@linkplain LinearScan#operandNumber(Value) * operand number}. */ public BitSet liveIn; /** * Bit map specifying which operands are live upon exit from this block. These are values * used in a successor block that are either defined in this block or were live upon entry * to this block. The bit index of an operand is its * {@linkplain LinearScan#operandNumber(Value) operand number}. */ public BitSet liveOut; /** * Bit map specifying which operands are used (before being defined) in this block. That is, * these are the values that are live upon entry to the block. The bit index of an operand * is its {@linkplain LinearScan#operandNumber(Value) operand number}. */ public BitSet liveGen; /** * Bit map specifying which operands are defined/overwritten in this block. The bit index of * an operand is its {@linkplain LinearScan#operandNumber(Value) operand number}. */ public BitSet liveKill; } private final BlockMap<BlockData> blockData; /** * List of blocks in linear-scan order. This is only correct as long as the CFG does not change. */ final List<? extends AbstractBlockBase<?>> sortedBlocks; /** @see #intervals() */ private Interval[] intervals; /** * The number of valid entries in {@link #intervals}. */ private int intervalsSize; /** * The index of the first entry in {@link #intervals} for a * {@linkplain #createDerivedInterval(Interval) derived interval}. */ private int firstDerivedIntervalIndex = -1; /** * Intervals sorted by {@link Interval#from()}. */ private Interval[] sortedIntervals; /** * Map from an instruction {@linkplain LIRInstruction#id id} to the instruction. Entries should * be retrieved with {@link #instructionForId(int)} as the id is not simply an index into this * array. */ private LIRInstruction[] opIdToInstructionMap; /** * Map from an instruction {@linkplain LIRInstruction#id id} to the * {@linkplain AbstractBlockBase block} containing the instruction. Entries should be retrieved * with {@link #blockForId(int)} as the id is not simply an index into this array. */ private AbstractBlockBase<?>[] opIdToBlockMap; /** * The {@linkplain #operandNumber(Value) number} of the first variable operand allocated. */ private final int firstVariableNumber; LinearScan(TargetDescription target, LIRGenerationResult res, SpillMoveFactory spillMoveFactory, RegisterAllocationConfig regAllocConfig) { this.res = res; this.ir = res.getLIR(); this.moveFactory = spillMoveFactory; this.frameMapBuilder = res.getFrameMapBuilder(); this.sortedBlocks = ir.linearScanOrder(); this.registerAttributes = regAllocConfig.getRegisterConfig().getAttributesMap(); this.regAllocConfig = regAllocConfig; this.registers = target.arch.getRegisters(); this.firstVariableNumber = registers.length; this.blockData = new BlockMap<>(ir.getControlFlowGraph()); /* * If all allocatable registers are caller saved, then no registers are live across a call * site. The register allocator can save time not trying to find a register at a call site. */ this.callKillsRegisters = regAllocConfig.getRegisterConfig().areAllAllocatableRegistersCallerSaved(); } int getFirstLirInstructionId(AbstractBlockBase<?> block) { int result = ir.getLIRforBlock(block).get(0).id(); assert result >= 0; return result; } int getLastLirInstructionId(AbstractBlockBase<?> block) { List<LIRInstruction> instructions = ir.getLIRforBlock(block); int result = instructions.get(instructions.size() - 1).id(); assert result >= 0; return result; } SpillMoveFactory getSpillMoveFactory() { return moveFactory; } protected MoveResolver createMoveResolver() { MoveResolver moveResolver = new MoveResolver(this); assert moveResolver.checkEmpty(); return moveResolver; } public static boolean isVariableOrRegister(Value value) { return isVariable(value) || isRegister(value); } /** * Converts an operand (variable or register) to an index in a flat address space covering all * the {@linkplain Variable variables} and {@linkplain RegisterValue registers} being processed * by this allocator. */ int operandNumber(Value operand) { if (isRegister(operand)) { int number = asRegister(operand).number; assert number < firstVariableNumber; return number; } assert isVariable(operand) : operand; return firstVariableNumber + ((Variable) operand).index; } /** * Gets the number of operands. This value will increase by 1 for new variable. */ int operandSize() { return firstVariableNumber + ir.numVariables(); } /** * Gets the highest operand number for a register operand. This value will never change. */ int maxRegisterNumber() { return firstVariableNumber - 1; } BlockData getBlockData(AbstractBlockBase<?> block) { return blockData.get(block); } void initBlockData(AbstractBlockBase<?> block) { blockData.put(block, new BlockData()); } static final IntervalPredicate IS_PRECOLORED_INTERVAL = new IntervalPredicate() { @Override public boolean apply(Interval i) { return isRegister(i.operand); } }; static final IntervalPredicate IS_VARIABLE_INTERVAL = new IntervalPredicate() { @Override public boolean apply(Interval i) { return isVariable(i.operand); } }; static final IntervalPredicate IS_STACK_INTERVAL = new IntervalPredicate() { @Override public boolean apply(Interval i) { return !isRegister(i.operand); } }; /** * Gets an object describing the attributes of a given register according to this register * configuration. */ RegisterAttributes attributes(Register reg) { return registerAttributes[reg.number]; } void assignSpillSlot(Interval interval) { /* * Assign the canonical spill slot of the parent (if a part of the interval is already * spilled) or allocate a new spill slot. */ if (interval.canMaterialize()) { interval.assignLocation(Value.ILLEGAL); } else if (interval.spillSlot() != null) { interval.assignLocation(interval.spillSlot()); } else { VirtualStackSlot slot = frameMapBuilder.allocateSpillSlot(interval.kind()); interval.setSpillSlot(slot); interval.assignLocation(slot); } } /** * Map from {@linkplain #operandNumber(Value) operand numbers} to intervals. */ Interval[] intervals() { return intervals; } void initIntervals() { intervalsSize = operandSize(); intervals = new Interval[intervalsSize + (intervalsSize >> SPLIT_INTERVALS_CAPACITY_RIGHT_SHIFT)]; } /** * Creates a new interval. * * @param operand the operand for the interval * @return the created interval */ Interval createInterval(AllocatableValue operand) { assert isLegal(operand); int operandNumber = operandNumber(operand); Interval interval = new Interval(operand, operandNumber); assert operandNumber < intervalsSize; assert intervals[operandNumber] == null; intervals[operandNumber] = interval; return interval; } /** * Creates an interval as a result of splitting or spilling another interval. * * @param source an interval being split of spilled * @return a new interval derived from {@code source} */ Interval createDerivedInterval(Interval source) { if (firstDerivedIntervalIndex == -1) { firstDerivedIntervalIndex = intervalsSize; } if (intervalsSize == intervals.length) { intervals = Arrays.copyOf(intervals, intervals.length + (intervals.length >> SPLIT_INTERVALS_CAPACITY_RIGHT_SHIFT)); } intervalsSize++; Variable variable = new Variable(source.kind(), ir.nextVariable()); Interval interval = createInterval(variable); assert intervals[intervalsSize - 1] == interval; return interval; } // access to block list (sorted in linear scan order) int blockCount() { return sortedBlocks.size(); } AbstractBlockBase<?> blockAt(int index) { return sortedBlocks.get(index); } /** * Gets the size of the {@link BlockData#liveIn} and {@link BlockData#liveOut} sets for a basic * block. These sets do not include any operands allocated as a result of creating * {@linkplain #createDerivedInterval(Interval) derived intervals}. */ int liveSetSize() { return firstDerivedIntervalIndex == -1 ? operandSize() : firstDerivedIntervalIndex; } int numLoops() { return ir.getControlFlowGraph().getLoops().size(); } Interval intervalFor(int operandNumber) { return intervals[operandNumber]; } Interval intervalFor(Value operand) { int operandNumber = operandNumber(operand); assert operandNumber < intervalsSize; return intervals[operandNumber]; } Interval getOrCreateInterval(AllocatableValue operand) { Interval ret = intervalFor(operand); if (ret == null) { return createInterval(operand); } else { return ret; } } void initOpIdMaps(int numInstructions) { opIdToInstructionMap = new LIRInstruction[numInstructions]; opIdToBlockMap = new AbstractBlockBase<?>[numInstructions]; } void putOpIdMaps(int index, LIRInstruction op, AbstractBlockBase<?> block) { opIdToInstructionMap[index] = op; opIdToBlockMap[index] = block; } /** * Gets the highest instruction id allocated by this object. */ int maxOpId() { assert opIdToInstructionMap.length > 0 : "no operations"; return (opIdToInstructionMap.length - 1) << 1; } /** * Converts an {@linkplain LIRInstruction#id instruction id} to an instruction index. All LIR * instructions in a method have an index one greater than their linear-scan order predecessor * with the first instruction having an index of 0. */ private static int opIdToIndex(int opId) { return opId >> 1; } /** * Retrieves the {@link LIRInstruction} based on its {@linkplain LIRInstruction#id id}. * * @param opId an instruction {@linkplain LIRInstruction#id id} * @return the instruction whose {@linkplain LIRInstruction#id} {@code == id} */ LIRInstruction instructionForId(int opId) { assert isEven(opId) : "opId not even"; LIRInstruction instr = opIdToInstructionMap[opIdToIndex(opId)]; assert instr.id() == opId; return instr; } /** * Gets the block containing a given instruction. * * @param opId an instruction {@linkplain LIRInstruction#id id} * @return the block containing the instruction denoted by {@code opId} */ AbstractBlockBase<?> blockForId(int opId) { assert opIdToBlockMap.length > 0 && opId >= 0 && opId <= maxOpId() + 1 : "opId out of range"; return opIdToBlockMap[opIdToIndex(opId)]; } boolean isBlockBegin(int opId) { return opId == 0 || blockForId(opId) != blockForId(opId - 1); } boolean coversBlockBegin(int opId1, int opId2) { return blockForId(opId1) != blockForId(opId2); } /** * Determines if an {@link LIRInstruction} destroys all caller saved registers. * * @param opId an instruction {@linkplain LIRInstruction#id id} * @return {@code true} if the instruction denoted by {@code id} destroys all caller saved * registers. */ boolean hasCall(int opId) { assert isEven(opId) : "opId not even"; return instructionForId(opId).destroysCallerSavedRegisters(); } abstract static class IntervalPredicate { abstract boolean apply(Interval i); } boolean isProcessed(Value operand) { return !isRegister(operand) || attributes(asRegister(operand)).isAllocatable(); } // * Phase 5: actual register allocation private static boolean isSorted(Interval[] intervals) { int from = -1; for (Interval interval : intervals) { assert interval != null; assert from <= interval.from(); from = interval.from(); } return true; } static Interval addToList(Interval first, Interval prev, Interval interval) { Interval newFirst = first; if (prev != null) { prev.next = interval; } else { newFirst = interval; } return newFirst; } Interval.Pair createUnhandledLists(IntervalPredicate isList1, IntervalPredicate isList2) { assert isSorted(sortedIntervals) : "interval list is not sorted"; Interval list1 = Interval.EndMarker; Interval list2 = Interval.EndMarker; Interval list1Prev = null; Interval list2Prev = null; Interval v; int n = sortedIntervals.length; for (int i = 0; i < n; i++) { v = sortedIntervals[i]; if (v == null) { continue; } if (isList1.apply(v)) { list1 = addToList(list1, list1Prev, v); list1Prev = v; } else if (isList2 == null || isList2.apply(v)) { list2 = addToList(list2, list2Prev, v); list2Prev = v; } } if (list1Prev != null) { list1Prev.next = Interval.EndMarker; } if (list2Prev != null) { list2Prev.next = Interval.EndMarker; } assert list1Prev == null || list1Prev.next == Interval.EndMarker : "linear list ends not with sentinel"; assert list2Prev == null || list2Prev.next == Interval.EndMarker : "linear list ends not with sentinel"; return new Interval.Pair(list1, list2); } void sortIntervalsBeforeAllocation() { int sortedLen = 0; for (Interval interval : intervals) { if (interval != null) { sortedLen++; } } Interval[] sortedList = new Interval[sortedLen]; int sortedIdx = 0; int sortedFromMax = -1; // special sorting algorithm: the original interval-list is almost sorted, // only some intervals are swapped. So this is much faster than a complete QuickSort for (Interval interval : intervals) { if (interval != null) { int from = interval.from(); if (sortedFromMax <= from) { sortedList[sortedIdx++] = interval; sortedFromMax = interval.from(); } else { // the assumption that the intervals are already sorted failed, // so this interval must be sorted in manually int j; for (j = sortedIdx - 1; j >= 0 && from < sortedList[j].from(); j--) { sortedList[j + 1] = sortedList[j]; } sortedList[j + 1] = interval; sortedIdx++; } } } sortedIntervals = sortedList; } void sortIntervalsAfterAllocation() { if (firstDerivedIntervalIndex == -1) { // no intervals have been added during allocation, so sorted list is already up to date return; } Interval[] oldList = sortedIntervals; Interval[] newList = Arrays.copyOfRange(intervals, firstDerivedIntervalIndex, intervalsSize); int oldLen = oldList.length; int newLen = newList.length; // conventional sort-algorithm for new intervals Arrays.sort(newList, (Interval a, Interval b) -> a.from() - b.from()); // merge old and new list (both already sorted) into one combined list Interval[] combinedList = new Interval[oldLen + newLen]; int oldIdx = 0; int newIdx = 0; while (oldIdx + newIdx < combinedList.length) { if (newIdx >= newLen || (oldIdx < oldLen && oldList[oldIdx].from() <= newList[newIdx].from())) { combinedList[oldIdx + newIdx] = oldList[oldIdx]; oldIdx++; } else { combinedList[oldIdx + newIdx] = newList[newIdx]; newIdx++; } } sortedIntervals = combinedList; } // wrapper for Interval.splitChildAtOpId that performs a bailout in product mode // instead of returning null Interval splitChildAtOpId(Interval interval, int opId, LIRInstruction.OperandMode mode) { Interval result = interval.getSplitChildAtOpId(opId, mode, this); if (result != null) { if (Debug.isLogEnabled()) { Debug.log("Split child at pos %d of interval %s is %s", opId, interval, result); } return result; } throw new BailoutException("LinearScan: interval is null"); } static StackSlotValue canonicalSpillOpr(Interval interval) { assert interval.spillSlot() != null : "canonical spill slot not set"; return interval.spillSlot(); } boolean isMaterialized(AllocatableValue operand, int opId, OperandMode mode) { Interval interval = intervalFor(operand); assert interval != null : "interval must exist"; if (opId != -1) { /* * Operands are not changed when an interval is split during allocation, so search the * right interval here. */ interval = splitChildAtOpId(interval, opId, mode); } return isIllegal(interval.location()) && interval.canMaterialize(); } boolean isCallerSave(Value operand) { return attributes(asRegister(operand)).isCallerSave(); } <B extends AbstractBlockBase<B>> void allocate(TargetDescription target, LIRGenerationResult lirGenRes, List<B> codeEmittingOrder, List<B> linearScanOrder, SpillMoveFactory spillMoveFactory, RegisterAllocationConfig registerAllocationConfig) { /* * This is the point to enable debug logging for the whole register allocation. */ try (Indent indent = Debug.logAndIndent("LinearScan allocate")) { AllocationContext context = new AllocationContext(spillMoveFactory, registerAllocationConfig); createLifetimeAnalysisPhase().apply(target, lirGenRes, codeEmittingOrder, linearScanOrder, context, false); try (Scope s = Debug.scope("AfterLifetimeAnalysis", intervals)) { sortIntervalsBeforeAllocation(); createRegisterAllocationPhase().apply(target, lirGenRes, codeEmittingOrder, linearScanOrder, context, false); if (LinearScan.Options.LSRAOptimizeSpillPosition.getValue()) { createOptimizeSpillPositionPhase().apply(target, lirGenRes, codeEmittingOrder, linearScanOrder, context, false); } createResolveDataFlowPhase().apply(target, lirGenRes, codeEmittingOrder, linearScanOrder, context); sortIntervalsAfterAllocation(); if (DetailedAsserts.getValue()) { verify(); } beforeSpillMoveElimination(); createSpillMoveEliminationPhase().apply(target, lirGenRes, codeEmittingOrder, linearScanOrder, context); createAssignLocationsPhase().apply(target, lirGenRes, codeEmittingOrder, linearScanOrder, context); if (DetailedAsserts.getValue()) { verifyIntervals(); } } catch (Throwable e) { throw Debug.handle(e); } } } protected void beforeSpillMoveElimination() { } protected LinearScanLifetimeAnalysisPhase createLifetimeAnalysisPhase() { return new LinearScanLifetimeAnalysisPhase(this); } protected LinearScanRegisterAllocationPhase createRegisterAllocationPhase() { return new LinearScanRegisterAllocationPhase(this); } protected LinearScanOptimizeSpillPositionPhase createOptimizeSpillPositionPhase() { return new LinearScanOptimizeSpillPositionPhase(this); } protected LinearScanResolveDataFlowPhase createResolveDataFlowPhase() { return new LinearScanResolveDataFlowPhase(this); } protected LinearScanEliminateSpillMovePhase createSpillMoveEliminationPhase() { return new LinearScanEliminateSpillMovePhase(this); } protected LinearScanAssignLocationsPhase createAssignLocationsPhase() { return new LinearScanAssignLocationsPhase(this); } void printIntervals(String label) { if (Debug.isLogEnabled()) { try (Indent indent = Debug.logAndIndent("intervals %s", label)) { for (Interval interval : intervals) { if (interval != null) { Debug.log("%s", interval.logString(this)); } } try (Indent indent2 = Debug.logAndIndent("Basic Blocks")) { for (int i = 0; i < blockCount(); i++) { AbstractBlockBase<?> block = blockAt(i); Debug.log("B%d [%d, %d, %s] ", block.getId(), getFirstLirInstructionId(block), getLastLirInstructionId(block), block.getLoop()); } } } } Debug.dump(Arrays.copyOf(intervals, intervalsSize), label); } void printLir(String label, @SuppressWarnings("unused") boolean hirValid) { Debug.dump(ir, label); } boolean verify() { // (check that all intervals have a correct register and that no registers are overwritten) verifyIntervals(); verifyRegisters(); Debug.log("no errors found"); return true; } private void verifyRegisters() { // Enable this logging to get output for the verification process. try (Indent indent = Debug.logAndIndent("verifying register allocation")) { RegisterVerifier verifier = new RegisterVerifier(this); verifier.verify(blockAt(0)); } } void verifyIntervals() { try (Indent indent = Debug.logAndIndent("verifying intervals")) { int len = intervalsSize; for (int i = 0; i < len; i++) { Interval i1 = intervals[i]; if (i1 == null) { continue; } i1.checkSplitChildren(); if (i1.operandNumber != i) { Debug.log("Interval %d is on position %d in list", i1.operandNumber, i); Debug.log(i1.logString(this)); throw new JVMCIError(""); } if (isVariable(i1.operand) && i1.kind().equals(LIRKind.Illegal)) { Debug.log("Interval %d has no type assigned", i1.operandNumber); Debug.log(i1.logString(this)); throw new JVMCIError(""); } if (i1.location() == null) { Debug.log("Interval %d has no register assigned", i1.operandNumber); Debug.log(i1.logString(this)); throw new JVMCIError(""); } if (i1.first() == Range.EndMarker) { Debug.log("Interval %d has no Range", i1.operandNumber); Debug.log(i1.logString(this)); throw new JVMCIError(""); } for (Range r = i1.first(); r != Range.EndMarker; r = r.next) { if (r.from >= r.to) { Debug.log("Interval %d has zero length range", i1.operandNumber); Debug.log(i1.logString(this)); throw new JVMCIError(""); } } for (int j = i + 1; j < len; j++) { Interval i2 = intervals[j]; if (i2 == null) { continue; } // special intervals that are created in MoveResolver // . ignore them because the range information has no meaning there if (i1.from() == 1 && i1.to() == 2) { continue; } if (i2.from() == 1 && i2.to() == 2) { continue; } Value l1 = i1.location(); Value l2 = i2.location(); if (i1.intersects(i2) && !isIllegal(l1) && (l1.equals(l2))) { if (DetailedAsserts.getValue()) { Debug.log("Intervals %d and %d overlap and have the same register assigned", i1.operandNumber, i2.operandNumber); Debug.log(i1.logString(this)); Debug.log(i2.logString(this)); } throw new BailoutException(""); } } } } } class CheckConsumer implements ValueConsumer { boolean ok; Interval curInterval; @Override public void visitValue(Value operand, OperandMode mode, EnumSet<OperandFlag> flags) { if (isRegister(operand)) { if (intervalFor(operand) == curInterval) { ok = true; } } } } void verifyNoOopsInFixedIntervals() { try (Indent indent = Debug.logAndIndent("verifying that no oops are in fixed intervals *")) { CheckConsumer checkConsumer = new CheckConsumer(); Interval fixedIntervals; Interval otherIntervals; fixedIntervals = createUnhandledLists(IS_PRECOLORED_INTERVAL, null).first; // to ensure a walking until the last instruction id, add a dummy interval // with a high operation id otherIntervals = new Interval(Value.ILLEGAL, -1); otherIntervals.addRange(Integer.MAX_VALUE - 2, Integer.MAX_VALUE - 1); IntervalWalker iw = new IntervalWalker(this, fixedIntervals, otherIntervals); for (AbstractBlockBase<?> block : sortedBlocks) { List<LIRInstruction> instructions = ir.getLIRforBlock(block); for (int j = 0; j < instructions.size(); j++) { LIRInstruction op = instructions.get(j); if (op.hasState()) { iw.walkBefore(op.id()); boolean checkLive = true; /* * Make sure none of the fixed registers is live across an oopmap since we * can't handle that correctly. */ if (checkLive) { for (Interval interval = iw.activeLists.get(RegisterBinding.Fixed); interval != Interval.EndMarker; interval = interval.next) { if (interval.currentTo() > op.id() + 1) { /* * This interval is live out of this op so make sure that this * interval represents some value that's referenced by this op * either as an input or output. */ checkConsumer.curInterval = interval; checkConsumer.ok = false; op.visitEachInput(checkConsumer); op.visitEachAlive(checkConsumer); op.visitEachTemp(checkConsumer); op.visitEachOutput(checkConsumer); assert checkConsumer.ok : "fixed intervals should never be live across an oopmap point"; } } } } } } } } }