Mercurial > hg > graal-compiler
view graal/com.oracle.truffle.api/src/com/oracle/truffle/api/CompilerDirectives.java @ 9290:17b598df8da9
Merge.
author | Doug Simon <doug.simon@oracle.com> |
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date | Thu, 25 Apr 2013 16:53:29 +0200 |
parents | 159ac409c27a |
children | 6369d37b37d1 |
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/* * Copyright (c) 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.truffle.api; import java.util.concurrent.*; /** * Directives that influence the optimizations of the Truffle compiler. All of the operations have * no effect when executed in the Truffle interpreter. */ public class CompilerDirectives { private static final double SLOWPATH_PROBABILITY = 0.0001; /** * Directive for the compiler to discontinue compilation at this code position and instead * insert a transfer to the interpreter. */ public static void transferToInterpreter() { } /** * Directive for the compiler that the given runnable should only be executed in the interpreter * and ignored in the compiled code. * * @param runnable the closure that should only be executed in the interpreter */ public static void interpreterOnly(Runnable runnable) { runnable.run(); } /** * Directive for the compiler that the given callable should only be executed in the * interpreter. * * @param callable the closure that should only be executed in the interpreter * @return the result of executing the closure in the interpreter and null in the compiled code * @throws Exception If the closure throws an exception when executed in the interpreter. */ public static <T> T interpreterOnly(Callable<T> callable) throws Exception { return callable.call(); } /** * Directive for the compiler that the current path has a very low probability to be executed. */ public static void slowpath() { injectBranchProbability(SLOWPATH_PROBABILITY); } /** * Injects a probability for the current path into the probability information of the * immediately preceeding branch instruction. * * @param probability the probability value between 0.0 and 1.0 that should be injected */ public static void injectBranchProbability(double probability) { assert probability >= 0.0 && probability <= 1.0; } /** * Bails out of a compilation (e.g., for guest language features that should never be compiled). * * @param reason the reason for the bailout */ public static void bailout(String reason) { } }