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 * 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.
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package org.graalvm.compiler.lir.alloc.trace;

import static org.graalvm.compiler.lir.LIRValueUtil.isStackSlotValue;
import static org.graalvm.compiler.lir.alloc.trace.TraceUtil.asShadowedRegisterValue;
import static org.graalvm.compiler.lir.alloc.trace.TraceUtil.isShadowedRegisterValue;
import static jdk.vm.ci.code.ValueUtil.asRegisterValue;
import static jdk.vm.ci.code.ValueUtil.isIllegal;
import static jdk.vm.ci.code.ValueUtil.isRegister;

import java.util.List;

import org.graalvm.compiler.core.common.alloc.Trace;
import org.graalvm.compiler.core.common.alloc.TraceBuilderResult;
import org.graalvm.compiler.core.common.cfg.AbstractBlockBase;
import org.graalvm.compiler.debug.Debug;
import org.graalvm.compiler.debug.Indent;
import org.graalvm.compiler.lir.LIR;
import org.graalvm.compiler.lir.LIRInstruction;
import org.graalvm.compiler.lir.alloc.trace.TraceAllocationPhase.TraceAllocationContext;
import org.graalvm.compiler.lir.gen.LIRGenerationResult;
import org.graalvm.compiler.lir.gen.LIRGeneratorTool.MoveFactory;
import org.graalvm.compiler.lir.phases.LIRPhase;
import org.graalvm.compiler.lir.ssa.SSAUtil.PhiValueVisitor;
import org.graalvm.compiler.lir.ssi.SSIUtil;

import jdk.vm.ci.code.Architecture;
import jdk.vm.ci.code.RegisterValue;
import jdk.vm.ci.code.TargetDescription;
import jdk.vm.ci.meta.AllocatableValue;
import jdk.vm.ci.meta.Value;

public final class TraceGlobalMoveResolutionPhase extends LIRPhase<TraceAllocationPhase.TraceAllocationContext> {

    
Abstract move resolver interface for testing.
/** * Abstract move resolver interface for testing. */
public abstract static class MoveResolver { public abstract void addMapping(Value src, AllocatableValue dst, Value fromStack); } @Override protected void run(TargetDescription target, LIRGenerationResult lirGenRes, TraceAllocationContext context) { MoveFactory spillMoveFactory = context.spillMoveFactory; resolveGlobalDataFlow(context.resultTraces, lirGenRes, spillMoveFactory, target.arch); } @SuppressWarnings("try") private static void resolveGlobalDataFlow(TraceBuilderResult resultTraces, LIRGenerationResult lirGenRes, MoveFactory spillMoveFactory, Architecture arch) { LIR lir = lirGenRes.getLIR(); /* Resolve trace global data-flow mismatch. */ TraceGlobalMoveResolver moveResolver = new TraceGlobalMoveResolver(lirGenRes, spillMoveFactory, arch); PhiValueVisitor visitor = (Value phiIn, Value phiOut) -> { if (!isIllegal(phiIn)) { addMapping(moveResolver, phiOut, phiIn); } }; try (Indent indent = Debug.logAndIndent("Trace global move resolution")) { for (Trace trace : resultTraces.getTraces()) { for (AbstractBlockBase<?> fromBlock : trace.getBlocks()) { for (AbstractBlockBase<?> toBlock : fromBlock.getSuccessors()) { if (resultTraces.getTraceForBlock(fromBlock) != resultTraces.getTraceForBlock(toBlock)) { try (Indent indent0 = Debug.logAndIndent("Handle trace edge from %s (Trace%d) to %s (Trace%d)", fromBlock, resultTraces.getTraceForBlock(fromBlock).getId(), toBlock, resultTraces.getTraceForBlock(toBlock).getId())) { final List<LIRInstruction> instructions; final int insertIdx; if (fromBlock.getSuccessorCount() == 1) { instructions = lir.getLIRforBlock(fromBlock); insertIdx = instructions.size() - 1; } else { assert toBlock.getPredecessorCount() == 1; instructions = lir.getLIRforBlock(toBlock); insertIdx = 1; } moveResolver.setInsertPosition(instructions, insertIdx); SSIUtil.forEachValuePair(lir, toBlock, fromBlock, visitor); moveResolver.resolveAndAppendMoves(); } } } } } } } public static void addMapping(MoveResolver moveResolver, Value from, Value to) { assert !isIllegal(to); if (isShadowedRegisterValue(to)) { ShadowedRegisterValue toSh = asShadowedRegisterValue(to); addMappingToRegister(moveResolver, from, toSh.getRegister()); addMappingToStackSlot(moveResolver, from, toSh.getStackSlot()); } else { if (isRegister(to)) { addMappingToRegister(moveResolver, from, asRegisterValue(to)); } else { assert isStackSlotValue(to) : "Expected stack slot: " + to; addMappingToStackSlot(moveResolver, from, (AllocatableValue) to); } } } private static void addMappingToRegister(MoveResolver moveResolver, Value from, RegisterValue register) { if (isShadowedRegisterValue(from)) { RegisterValue fromReg = asShadowedRegisterValue(from).getRegister(); AllocatableValue fromStack = asShadowedRegisterValue(from).getStackSlot(); checkAndAddMapping(moveResolver, fromReg, register, fromStack); } else { checkAndAddMapping(moveResolver, from, register, null); } } private static void addMappingToStackSlot(MoveResolver moveResolver, Value from, AllocatableValue stack) { if (isShadowedRegisterValue(from)) { ShadowedRegisterValue shadowedFrom = asShadowedRegisterValue(from); RegisterValue fromReg = shadowedFrom.getRegister(); AllocatableValue fromStack = shadowedFrom.getStackSlot(); if (!fromStack.equals(stack)) { checkAndAddMapping(moveResolver, fromReg, stack, fromStack); } } else { checkAndAddMapping(moveResolver, from, stack, null); } } private static void checkAndAddMapping(MoveResolver moveResolver, Value from, AllocatableValue to, AllocatableValue fromStack) { if (!from.equals(to) && (fromStack == null || !fromStack.equals(to))) { moveResolver.addMapping(from, to, fromStack); } } }