Mercurial > hg > truffle
view graal/com.oracle.max.graal.nodes/src/com/oracle/max/graal/nodes/java/CheckCastNode.java @ 4309:4a609a685fa4
changes to Node structures:
* add more uses of higher-level graph manipulation methods
* CanonicalierPhase cleanup
* introduce FloatingReadNode, make ReadNode an ordinary fixed nodeToBlock
* let Canonicalizable.canonical return ValueNode (instead of Node)
author | Lukas Stadler <lukas.stadler@jku.at> |
---|---|
date | Tue, 17 Jan 2012 19:45:39 +0100 |
parents | aaac4894175c |
children | be4914c1c799 |
line wrap: on
line source
/* * 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.oracle.max.graal.nodes.java; import com.oracle.max.cri.ci.*; import com.oracle.max.cri.ri.*; import com.oracle.max.graal.nodes.*; import com.oracle.max.graal.nodes.extended.*; import com.oracle.max.graal.nodes.spi.*; import com.oracle.max.graal.nodes.type.*; /** * The {@code CheckCastNode} represents a {@link Bytecodes#CHECKCAST}. */ public final class CheckCastNode extends TypeCheckNode implements Canonicalizable, LIRLowerable { @Input protected final AnchorNode anchor; /** * Creates a new CheckCast instruction. * * @param targetClassInstruction the instruction which produces the class which is being cast to * @param targetClass the class being cast to * @param object the instruction producing the object */ public CheckCastNode(AnchorNode anchor, ValueNode targetClassInstruction, RiResolvedType targetClass, ValueNode object) { super(targetClassInstruction, targetClass, object, targetClass == null ? StampFactory.forKind(CiKind.Object) : StampFactory.declared(targetClass)); this.anchor = anchor; } @Override public void generate(LIRGeneratorTool gen) { gen.visitCheckCast(this); } @Override public ValueNode canonical(CanonicalizerTool tool) { RiResolvedType objectDeclaredType = object().declaredType(); RiResolvedType targetClass = targetClass(); if (objectDeclaredType != null && targetClass != null && objectDeclaredType.isSubtypeOf(targetClass)) { freeAnchor(); return object(); } CiConstant constant = object().asConstant(); if (constant != null) { assert constant.kind == CiKind.Object; if (constant.isNull()) { freeAnchor(); return object(); } } return this; } // TODO(tw): Find a better way to handle anchors. private void freeAnchor() { ValueAnchorNode anchorUsage = usages().filter(ValueAnchorNode.class).first(); if (anchorUsage != null) { anchorUsage.replaceFirstInput(this, null); } } @Override public BooleanNode negate() { throw new Error("A CheckCast does not produce a boolean value, so it should actually not be a subclass of BooleanNode"); } }