Mercurial > hg > graal-compiler
view graal/com.oracle.truffle.api/src/com/oracle/truffle/api/utilities/AssumedValue.java @ 15262:cd51b1253c4c
replaced the link between a HotSpotResolvedJavaMethod and a SpeculationLog with a ClassValue based mechanism (GRAAL-727)
author | Doug Simon <doug.simon@oracle.com> |
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date | Tue, 22 Apr 2014 15:46:06 +0200 |
parents | f28ea693056f |
children | 0e7894989f37 |
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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. Oracle designates this * particular file as subject to the "Classpath" exception as provided * by Oracle in the LICENSE file that accompanied this code. * * 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.utilities; import com.oracle.truffle.api.*; import com.oracle.truffle.api.CompilerDirectives.CompilationFinal; import com.oracle.truffle.api.nodes.*; /** * A {@link CompilationFinal} value combined with an {@link Assumption} to notify when it changes. * Note that you should be careful that modifications to this value do not cause deoptimization * loops. This could be by using a value that is monotonic. */ public class AssumedValue<T> { @CompilationFinal private T value; private final CyclicAssumption assumption; public AssumedValue(String name, T initialValue) { assumption = new CyclicAssumption(name); value = initialValue; } /** * Get the current value, updating it if it has been {@link #set}. The compiler may be able to * make this method return a constant value, but still accommodate mutation. */ public T get() { try { assumption.getAssumption().check(); } catch (InvalidAssumptionException e) { // No need to rewrite anything - just pick up the new value } return value; } /** * Set a new value, which will be picked up the next time {@link #get} is called. */ public void set(T newValue) { value = newValue; assumption.invalidate(); } }