1 /* 2 * Copyright (c) 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.amd64; 24 25 import org.graalvm.compiler.asm.amd64.AMD64MacroAssembler; 26 import org.graalvm.compiler.lir.LIRInstructionClass; 27 import org.graalvm.compiler.lir.Opcode; 28 import org.graalvm.compiler.lir.asm.CompilationResultBuilder; 29 30 import jdk.vm.ci.code.StackSlot; 31 import jdk.vm.ci.meta.JavaConstant; 32 33 /** 34 * Writes well known garbage values to stack slots. 35 */ 36 @Opcode("ZAP_STACK") 37 public final class AMD64ZapStackOp extends AMD64LIRInstruction { 38 public static final LIRInstructionClass<AMD64ZapStackOp> TYPE = LIRInstructionClass.create(AMD64ZapStackOp.class); 39 40 /** 41 * The stack slots that are zapped. 42 */ 43 @Def(OperandFlag.STACK) protected final StackSlot[] zappedStack; 44 45 /** 46 * The garbage values that are written to the stack. 47 */ 48 protected final JavaConstant[] zapValues; 49 50 public AMD64ZapStackOp(StackSlot[] zappedStack, JavaConstant[] zapValues) { 51 super(TYPE); 52 this.zappedStack = zappedStack; 53 this.zapValues = zapValues; 54 } 55 56 @Override 57 public void emitCode(CompilationResultBuilder crb, AMD64MacroAssembler masm) { 58 for (int i = 0; i < zappedStack.length; i++) { 59 StackSlot slot = zappedStack[i]; 60 if (slot != null) { 61 AMD64Move.const2stack(crb, masm, slot, zapValues[i]); 62 } 63 } 64 } 65 }