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.copyms;
014    
015    import org.mmtk.plan.StopTheWorldConstraints;
016    
017    import org.mmtk.policy.CopySpace;
018    import org.mmtk.policy.SegregatedFreeListSpace;
019    
020    import org.vmmagic.pragma.*;
021    
022    /**
023     * This class and its subclasses communicate to the host VM/Runtime
024     * any features of the selected plan that it needs to know.  This is
025     * separate from the main Plan/PlanLocal class in order to bypass any
026     * issues with ordering of static initialization.
027     */
028    @Uninterruptible
029    public class CopyMSConstraints extends StopTheWorldConstraints {
030    
031      @Override
032      public int gcHeaderBits() { return CopySpace.LOCAL_GC_BITS_REQUIRED; }
033      @Override
034      public int gcHeaderWords() { return CopySpace.GC_HEADER_WORDS_REQUIRED; }
035      @Override
036      public int numSpecializedScans() { return 1; }
037      @Override
038      public boolean movesObjects() { return true; }
039      @Override
040      public int maxNonLOSCopyBytes() { return SegregatedFreeListSpace.MAX_FREELIST_OBJECT_BYTES;}
041    }