Mercurial > hg > truffle
view graal/com.oracle.graal.replacements/src/com/oracle/graal/replacements/nodes/BranchProbabilityNode.java @ 8436:10293cbfc2b6
wrote implementations for node intrinsics so that they can be interpreted when a method substitution is deoptimized and added unit tests to ensure existing method substitutions can run interpreted
author | Doug Simon <doug.simon@oracle.com> |
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date | Fri, 22 Mar 2013 11:19:53 +0100 |
parents | 102b5249e97e |
children | 2ffd472c5d25 |
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/* * Copyright (c) 2012, 2013, 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.replacements.nodes; import com.oracle.graal.nodes.*; import com.oracle.graal.nodes.spi.*; import com.oracle.graal.nodes.type.*; import com.oracle.graal.nodes.util.*; /** * Instances of this node class will look for a preceding if node and put the given probability into * the if node's taken probability. Then the branch probability node will be removed. This node is * intended primarily for snippets, so that they can define their fast and slow paths. */ public class BranchProbabilityNode extends FixedWithNextNode implements Simplifiable { public static final double LIKELY_PROBABILITY = 0.6; public static final double NOT_LIKELY_PROBABILITY = 1 - LIKELY_PROBABILITY; public static final double FREQUENT_PROBABILITY = 0.9; public static final double NOT_FREQUENT_PROBABILITY = 1 - FREQUENT_PROBABILITY; public static final double FAST_PATH_PROBABILITY = 0.99; public static final double SLOW_PATH_PROBABILITY = 1 - FAST_PATH_PROBABILITY; public static final double NOT_DEOPT_PATH_PROBABILITY = 0.999; public static final double DEOPT_PATH_PROBABILITY = 1 - NOT_DEOPT_PATH_PROBABILITY; private final double probability; public BranchProbabilityNode(double probability) { super(StampFactory.forVoid()); assert probability >= 0 && probability <= 1; this.probability = probability; } @Override public void simplify(SimplifierTool tool) { FixedNode current = this; while (!(current instanceof BeginNode)) { current = (FixedNode) current.predecessor(); } BeginNode begin = (BeginNode) current; assert begin.predecessor() instanceof IfNode : "explicit branch probability cannot follow a merge, only if nodes"; IfNode ifNode = (IfNode) begin.predecessor(); if (ifNode.trueSuccessor() == begin) { ifNode.setTrueSuccessorProbability(probability); } else { ifNode.setTrueSuccessorProbability(1 - probability); } FixedNode next = next(); setNext(null); ((FixedWithNextNode) predecessor()).setNext(next); GraphUtil.killCFG(this); } @SuppressWarnings("unused") @NodeIntrinsic public static void probability(@ConstantNodeParameter double probability) { } }