Mercurial > hg > truffle
view graal/com.oracle.graal.lir.amd64/src/com/oracle/graal/lir/amd64/AMD64SaveRegistersOp.java @ 12613:595f01abb887
clearer API and documentation for the capability of a SaveRegistersOp to have its registers pruned
author | Doug Simon <doug.simon@oracle.com> |
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date | Sun, 27 Oct 2013 19:59:00 +0100 |
parents | 62fb4919edc9 |
children | 1a66453f73db |
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/* * Copyright (c) 2013, 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.amd64; import static com.oracle.graal.lir.LIRInstruction.OperandFlag.*; import java.util.*; import com.oracle.graal.api.code.*; import com.oracle.graal.asm.amd64.*; import com.oracle.graal.lir.*; import com.oracle.graal.lir.StandardOp.SaveRegistersOp; import com.oracle.graal.lir.asm.*; /** * Saves registers to stack slots. */ @Opcode("SAVE_REGISTER") public class AMD64SaveRegistersOp extends AMD64LIRInstruction implements SaveRegistersOp { /** * The registers (potentially) saved by this operation. */ protected final Register[] savedRegisters; /** * The slots to which the registers are saved. */ @Def(STACK) protected final StackSlot[] slots; /** * Specifies if {@link #remove(Set)} should have an effect. */ protected final boolean supportsRemove; /** * * @param savedRegisters the registers saved by this operation which may be subject to * {@linkplain #remove(Set) pruning} * @param slots the slots to which the registers are saved * @param supportsRemove determines if registers can be {@linkplain #remove(Set) pruned} */ public AMD64SaveRegistersOp(Register[] savedRegisters, StackSlot[] slots, boolean supportsRemove) { this.savedRegisters = savedRegisters; this.slots = slots; this.supportsRemove = supportsRemove; } protected void saveRegister(TargetMethodAssembler tasm, AMD64MacroAssembler masm, StackSlot result, Register register) { RegisterValue input = register.asValue(result.getKind()); AMD64Move.move(tasm, masm, result, input); } @Override public void emitCode(TargetMethodAssembler tasm, AMD64MacroAssembler masm) { for (int i = 0; i < savedRegisters.length; i++) { if (savedRegisters[i] != null) { saveRegister(tasm, masm, slots[i], savedRegisters[i]); } } } public StackSlot[] getSlots() { return slots; } public boolean supportsRemove() { return supportsRemove; } public int remove(Set<Register> doNotSave) { if (!supportsRemove) { throw new UnsupportedOperationException(); } return prune(doNotSave, savedRegisters); } static int prune(Set<Register> toRemove, Register[] registers) { int pruned = 0; for (int i = 0; i < registers.length; i++) { if (registers[i] != null) { if (toRemove.contains(registers[i])) { registers[i] = null; pruned++; } } } return pruned; } public RegisterSaveLayout getMap(FrameMap frameMap) { int total = 0; for (int i = 0; i < savedRegisters.length; i++) { if (savedRegisters[i] != null) { total++; } } Register[] keys = new Register[total]; int[] values = new int[total]; if (total != 0) { int mapIndex = 0; for (int i = 0; i < savedRegisters.length; i++) { if (savedRegisters[i] != null) { keys[mapIndex] = savedRegisters[i]; values[mapIndex] = frameMap.indexForStackSlot(slots[i]); mapIndex++; } } assert mapIndex == total; } return new RegisterSaveLayout(keys, values); } }