Mercurial > hg > truffle
view graal/com.oracle.graal.nodes/src/com/oracle/graal/nodes/calc/PointerEqualsNode.java @ 21678:7355942cb270
Improve lowering of the type check node.
author | Thomas Wuerthinger <thomas.wuerthinger@oracle.com> |
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date | Wed, 03 Jun 2015 01:10:18 +0200 |
parents | 48c1ebd24120 |
children |
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/* * Copyright (c) 2011, 2015, 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.compiler.common.calc.*; import com.oracle.graal.compiler.common.type.*; import com.oracle.graal.graph.*; import com.oracle.graal.graph.spi.Canonicalizable.BinaryCommutative; import com.oracle.graal.graph.spi.*; import com.oracle.graal.nodeinfo.*; import com.oracle.graal.nodes.*; import com.oracle.graal.nodes.util.*; import com.oracle.jvmci.meta.*; @NodeInfo(shortName = "==") public class PointerEqualsNode extends CompareNode implements BinaryCommutative<ValueNode> { public static final NodeClass<PointerEqualsNode> TYPE = NodeClass.create(PointerEqualsNode.class); public PointerEqualsNode(ValueNode x, ValueNode y) { this(TYPE, x, y); } public static LogicNode create(ValueNode x, ValueNode y) { LogicNode result = findSynonym(x, y); if (result != null) { return result; } return new PointerEqualsNode(x, y); } protected PointerEqualsNode(NodeClass<? extends PointerEqualsNode> c, ValueNode x, ValueNode y) { super(c, Condition.EQ, false, x, y); assert x.stamp() instanceof AbstractPointerStamp; assert y.stamp() instanceof AbstractPointerStamp; } @Override public ValueNode canonical(CanonicalizerTool tool, ValueNode forX, ValueNode forY) { LogicNode result = findSynonym(forX, forY); if (result != null) { return result; } return super.canonical(tool, forX, forY); } public static LogicNode findSynonym(ValueNode forX, ValueNode forY) { if (GraphUtil.unproxify(forX) == GraphUtil.unproxify(forY)) { return LogicConstantNode.tautology(); } else if (forX.stamp().alwaysDistinct(forY.stamp())) { return LogicConstantNode.contradiction(); } else if (((AbstractPointerStamp) forX.stamp()).alwaysNull()) { return new IsNullNode(forY); } else if (((AbstractPointerStamp) forY.stamp()).alwaysNull()) { return new IsNullNode(forX); } else { return null; } } @Override protected CompareNode duplicateModified(ValueNode newX, ValueNode newY) { return new PointerEqualsNode(newX, newY); } @Override public Stamp getSucceedingStampForX(boolean negated) { if (!negated) { Stamp xStamp = getX().stamp(); Stamp newStamp = xStamp.join(getY().stamp()); if (!newStamp.equals(xStamp)) { return newStamp; } } return null; } @Override public Stamp getSucceedingStampForY(boolean negated) { if (!negated) { Stamp yStamp = getY().stamp(); Stamp newStamp = yStamp.join(getX().stamp()); if (!newStamp.equals(yStamp)) { return newStamp; } } return null; } @Override public TriState tryFold(Stamp xStampGeneric, Stamp yStampGeneric) { if (xStampGeneric instanceof ObjectStamp && yStampGeneric instanceof ObjectStamp) { ObjectStamp xStamp = (ObjectStamp) xStampGeneric; ObjectStamp yStamp = (ObjectStamp) yStampGeneric; if (xStamp.alwaysDistinct(yStamp)) { return TriState.FALSE; } else if (xStamp.neverDistinct(yStamp)) { return TriState.TRUE; } } return TriState.UNKNOWN; } }