001    /*
002     *  This file is part of the Jikes RVM project (http://jikesrvm.org).
003     *
004     *  This file is licensed to You under the Eclipse Public License (EPL);
005     *  You may not use this file except in compliance with the License. You
006     *  may obtain a copy of the License at
007     *
008     *      http://www.opensource.org/licenses/eclipse-1.0.php
009     *
010     *  See the COPYRIGHT.txt file distributed with this work for information
011     *  regarding copyright ownership.
012     */
013    package org.mmtk.plan.concurrent;
014    
015    import org.mmtk.plan.SimpleConstraints;
016    import org.vmmagic.pragma.*;
017    
018    /**
019     * This class and its subclasses communicate to the host VM/Runtime
020     * any features of the selected plan that it needs to know.  This is
021     * separate from the main Plan/PlanLocal class in order to bypass any
022     * issues with ordering of static initialization.
023     */
024    @Uninterruptible
025    public abstract class ConcurrentConstraints extends SimpleConstraints {
026      @Override
027      public boolean needsConcurrentWorkers() { return true; }
028    
029      @Override
030      public boolean needsObjectReferenceWriteBarrier() { return true; }
031    
032      @Override
033      public boolean needsJavaLangReferenceReadBarrier() { return true; }
034    
035      //@Override
036      // TODO public boolean needsStaticWriteBarrier() { return true; }
037    }