Mercurial > hg > truffle
view graal/com.oracle.max.graal.nodes/src/com/oracle/max/graal/nodes/IfNode.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 | e233f5660da4 |
children | 72d099e5be61 |
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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.oracle.max.graal.nodes; import com.oracle.max.graal.nodes.spi.*; import com.oracle.max.graal.nodes.type.*; /** * The {@code IfNode} represents a branch that can go one of two directions depending on the outcome of a * comparison. */ public final class IfNode extends ControlSplitNode implements Canonicalizable, LIRLowerable { private static final BeginNode[] EMPTY_IF_SUCCESSORS = new BeginNode[] {null, null}; @Input private BooleanNode compare; public BooleanNode compare() { return compare; } public IfNode(BooleanNode condition, FixedNode trueSuccessor, FixedNode falseSuccessor, double probability) { super(StampFactory.illegal(), new BeginNode[] {BeginNode.begin(trueSuccessor), BeginNode.begin(falseSuccessor)}, new double[] {probability, 1 - probability}); this.compare = condition; } public IfNode(BooleanNode condition, double probability) { super(StampFactory.illegal(), EMPTY_IF_SUCCESSORS, new double[] {probability, 1 - probability}); this.compare = condition; } /** * Gets the true successor. * * @return the true successor */ public BeginNode trueSuccessor() { return blockSuccessor(0); } /** * Gets the false successor. * * @return the false successor */ public BeginNode falseSuccessor() { return blockSuccessor(1); } public void setTrueSuccessor(BeginNode node) { setBlockSuccessor(0, node); } public void setFalseSuccessor(BeginNode node) { setBlockSuccessor(1, node); } /** * Gets the node corresponding to the specified outcome of the branch. * * @param istrue {@code true} if the true successor is requested, {@code false} otherwise * @return the corresponding successor */ public FixedNode successor(boolean istrue) { return blockSuccessor(istrue ? 0 : 1); } @Override public void generate(LIRGeneratorTool gen) { gen.emitIf(this); } @Override public boolean verify() { assertTrue(compare() != null, "missing compare"); assertTrue(trueSuccessor() != null, "missing trueSuccessor"); assertTrue(falseSuccessor() != null, "missing falseSuccessor"); return super.verify(); } @Override public ValueNode canonical(CanonicalizerTool tool) { if (compare() instanceof ConstantNode) { ConstantNode c = (ConstantNode) compare(); if (c.asConstant().asBoolean()) { tool.deleteBranch(falseSuccessor()); return trueSuccessor(); } else { tool.deleteBranch(trueSuccessor()); return falseSuccessor(); } } if (trueSuccessor().next() instanceof EndNode && falseSuccessor().next() instanceof EndNode) { EndNode trueEnd = (EndNode) trueSuccessor().next(); EndNode falseEnd = (EndNode) falseSuccessor().next(); MergeNode merge = trueEnd.merge(); if (merge == falseEnd.merge() && !merge.phis().iterator().hasNext() && merge.endCount() == 2) { FixedNode next = merge.next(); merge.safeDelete(); BeginNode falseSuccessor = this.falseSuccessor(); BeginNode trueSuccessor = this.trueSuccessor(); this.setTrueSuccessor(null); this.setFalseSuccessor(null); trueSuccessor.safeDelete(); falseSuccessor.safeDelete(); trueEnd.safeDelete(); falseEnd.safeDelete(); return next; } } return this; } }