1 /*
   2  * Copyright (c) 2016, 2016, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  */
  23 package org.graalvm.compiler.lir.alloc;
  24 
  25 import java.util.ArrayList;
  26 
  27 import org.graalvm.compiler.core.common.LIRKind;
  28 import org.graalvm.compiler.core.common.cfg.AbstractBlockBase;
  29 import org.graalvm.compiler.lir.LIR;
  30 import org.graalvm.compiler.lir.LIRInsertionBuffer;
  31 import org.graalvm.compiler.lir.LIRInstruction;
  32 import org.graalvm.compiler.lir.StandardOp;
  33 import org.graalvm.compiler.lir.Variable;
  34 import org.graalvm.compiler.lir.gen.LIRGenerationResult;
  35 import org.graalvm.compiler.lir.gen.LIRGeneratorTool;
  36 import org.graalvm.compiler.lir.phases.PreAllocationOptimizationPhase;
  37 import org.graalvm.compiler.lir.util.RegisterMap;
  38 
  39 import jdk.vm.ci.code.Architecture;
  40 import jdk.vm.ci.code.Register;
  41 import jdk.vm.ci.code.RegisterArray;
  42 import jdk.vm.ci.code.RegisterValue;
  43 import jdk.vm.ci.code.TargetDescription;
  44 import jdk.vm.ci.meta.PlatformKind;
  45 
  46 public class SaveCalleeSaveRegisters extends PreAllocationOptimizationPhase {
  47 
  48     @Override
  49     protected void run(TargetDescription target, LIRGenerationResult lirGenRes, PreAllocationOptimizationContext context) {
  50         RegisterArray calleeSaveRegisters = lirGenRes.getRegisterConfig().getCalleeSaveRegisters();
  51         if (calleeSaveRegisters == null || calleeSaveRegisters.size() == 0) {
  52             return;
  53         }
  54         LIR lir = lirGenRes.getLIR();
  55         RegisterMap<Variable> savedRegisters = saveAtEntry(lir, context.lirGen, lirGenRes, calleeSaveRegisters, target.arch);
  56 
  57         for (AbstractBlockBase<?> block : lir.codeEmittingOrder()) {
  58             if (block == null) {
  59                 continue;
  60             }
  61             if (block.getSuccessorCount() == 0) {
  62                 restoreAtExit(lir, context.lirGen.getSpillMoveFactory(), lirGenRes, savedRegisters, block);
  63             }
  64         }
  65     }
  66 
  67     private static RegisterMap<Variable> saveAtEntry(LIR lir, LIRGeneratorTool lirGen, LIRGenerationResult lirGenRes, RegisterArray calleeSaveRegisters, Architecture arch) {
  68         AbstractBlockBase<?> startBlock = lir.getControlFlowGraph().getStartBlock();
  69         ArrayList<LIRInstruction> instructions = lir.getLIRforBlock(startBlock);
  70         int insertionIndex = 1;
  71         LIRInsertionBuffer buffer = new LIRInsertionBuffer();
  72         buffer.init(instructions);
  73         StandardOp.LabelOp entry = (StandardOp.LabelOp) instructions.get(insertionIndex - 1);
  74         RegisterValue[] savedRegisterValues = new RegisterValue[calleeSaveRegisters.size()];
  75         int savedRegisterValueIndex = 0;
  76         RegisterMap<Variable> saveMap = new RegisterMap<>(arch);
  77         for (Register register : calleeSaveRegisters) {
  78             PlatformKind registerPlatformKind = arch.getLargestStorableKind(register.getRegisterCategory());
  79             LIRKind lirKind = LIRKind.value(registerPlatformKind);
  80             RegisterValue registerValue = register.asValue(lirKind);
  81             Variable saveVariable = lirGen.newVariable(lirKind);
  82             LIRInstruction save = lirGen.getSpillMoveFactory().createMove(saveVariable, registerValue);
  83             buffer.append(insertionIndex, save);
  84             save.setComment(lirGenRes, "SaveCalleeSavedRegisters: saveAtEntry");
  85             saveMap.put(register, saveVariable);
  86             savedRegisterValues[savedRegisterValueIndex++] = registerValue;
  87         }
  88         entry.addIncomingValues(savedRegisterValues);
  89         buffer.finish();
  90         return saveMap;
  91     }
  92 
  93     private static void restoreAtExit(LIR lir, LIRGeneratorTool.MoveFactory moveFactory, LIRGenerationResult lirGenRes, RegisterMap<Variable> calleeSaveRegisters, AbstractBlockBase<?> block) {
  94         ArrayList<LIRInstruction> instructions = lir.getLIRforBlock(block);
  95         int insertionIndex = instructions.size() - 1;
  96         LIRInsertionBuffer buffer = new LIRInsertionBuffer();
  97         buffer.init(instructions);
  98         assert instructions.get(insertionIndex) instanceof StandardOp.BlockEndOp;
  99         calleeSaveRegisters.forEach((Register register, Variable saved) -> {
 100             LIRInstruction restore = moveFactory.createMove(register.asValue(saved.getValueKind()), saved);
 101             buffer.append(insertionIndex, restore);
 102             restore.setComment(lirGenRes, "SaveCalleeSavedRegisters: restoreAtExit");
 103         });
 104         buffer.finish();
 105     }
 106 }