Mercurial > hg > graal-compiler
view graal/GraalCompiler/src/com/sun/c1x/ir/NullCheck.java @ 2610:39aa89baa165
cleanup: FrameState copy methods, ImmutableFrameState
author | Lukas Stadler <lukas.stadler@jku.at> |
---|---|
date | Fri, 06 May 2011 13:03:33 +0200 |
parents | f1bc67c2d453 |
children | 91d3952f7eb7 |
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/* * Copyright (c) 2009, 2011, 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.sun.c1x.ir; import com.oracle.graal.graph.*; import com.sun.c1x.debug.*; import com.sun.c1x.util.*; import com.sun.c1x.value.*; import com.sun.cri.bytecode.*; import com.sun.cri.ri.*; /** * The {@code NullCheck} class represents an explicit null check instruction. */ public final class NullCheck extends StateSplit { private static final int INPUT_COUNT = 1; private static final int INPUT_OBJECT = 0; private static final int SUCCESSOR_COUNT = 0; @Override protected int inputCount() { return super.inputCount() + INPUT_COUNT; } @Override protected int successorCount() { return super.successorCount() + SUCCESSOR_COUNT; } /** * The instruction that produces the object tested against null. */ public Value object() { return (Value) inputs().get(super.inputCount() + INPUT_OBJECT); } public Value setObject(Value n) { return (Value) inputs().set(super.inputCount() + INPUT_OBJECT, n); } /** * Constructs a new NullCheck instruction. * @param object the instruction producing the object to check against null * @param stateBefore the state before executing the null check * @param graph */ public NullCheck(Value object, FrameState stateBefore, Graph graph) { super(object.kind, stateBefore, INPUT_COUNT, SUCCESSOR_COUNT, graph); setFlag(Flag.NonNull); setObject(object); } @Override public void accept(ValueVisitor v) { v.visitNullCheck(this); } @Override public int valueNumber() { return Util.hash1(Bytecodes.IFNONNULL, object()); } @Override public boolean valueEqual(Instruction i) { if (i instanceof NullCheck) { NullCheck o = (NullCheck) i; return object() == o.object(); } return false; } @Override public RiType declaredType() { // null check does not alter the type of the object return object().declaredType(); } @Override public RiType exactType() { // null check does not alter the type of the object return object().exactType(); } @Override public void print(LogStream out) { out.print("null_check(").print(object()).print(')'); if (!canTrap()) { out.print(" (eliminated)"); } } }