Mercurial > hg > truffle
view graal/com.oracle.graal.nodes/src/com/oracle/graal/nodes/calc/ObjectEqualsNode.java @ 6710:6db6881c1270
add Virtualizable and VirtualizerTool, refactor PEA to use it
author | Lukas Stadler <lukas.stadler@jku.at> |
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date | Mon, 12 Nov 2012 17:49:06 +0100 |
parents | ed08c40d67de |
children | 94f032472c28 |
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/* * Copyright (c) 2011, 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.oracle.graal.nodes.calc; import com.oracle.graal.api.meta.*; import com.oracle.graal.graph.*; import com.oracle.graal.nodes.*; import com.oracle.graal.nodes.spi.*; import com.oracle.graal.nodes.virtual.*; @NodeInfo(shortName = "==") public final class ObjectEqualsNode extends CompareNode implements Virtualizable { /** * Constructs a new object equality comparison node. * * @param x the instruction producing the first input to the instruction * @param y the instruction that produces the second input to this instruction */ public ObjectEqualsNode(ValueNode x, ValueNode y) { super(x, y); assert x.kind() == Kind.Object; assert y.kind() == Kind.Object; } @Override public Condition condition() { return Condition.EQ; } @Override public boolean unorderedIsTrue() { return false; } @Override public ValueNode canonical(CanonicalizerTool tool) { if (x() == y()) { return ConstantNode.forBoolean(true, graph()); } if (x().objectStamp().alwaysNull()) { return graph().unique(new IsNullNode(y())); } else if (y().objectStamp().alwaysNull()) { return graph().unique(new IsNullNode(x())); } if (x().stamp().alwaysDistinct(y().stamp())) { return ConstantNode.forBoolean(false, graph()); } return super.canonical(tool); } @Override public void virtualize(VirtualizerTool tool) { VirtualObjectNode virtualX = tool.getVirtualState(x()); VirtualObjectNode virtualY = tool.getVirtualState(y()); boolean xVirtual = virtualX != null; boolean yVirtual = virtualY != null; if (xVirtual ^ yVirtual) { // one of them is virtual: they can never be the same objects tool.replaceWithValue(ConstantNode.forBoolean(false, graph())); } else if (xVirtual && yVirtual) { // both are virtual: check if they refer to the same object tool.replaceWithValue(ConstantNode.forBoolean(virtualX == virtualY, graph())); } } }