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.semispace;
014    
015    import org.mmtk.plan.*;
016    import org.mmtk.policy.CopySpace;
017    import org.vmmagic.pragma.*;
018    
019    /**
020     * SemiSpace common constants.
021     */
022    @Uninterruptible
023    public class SSConstraints extends StopTheWorldConstraints {
024      @Override
025      public boolean movesObjects() { return true; }
026      @Override
027      public int gcHeaderBits() { return CopySpace.LOCAL_GC_BITS_REQUIRED; }
028      @Override
029      public int gcHeaderWords() { return CopySpace.GC_HEADER_WORDS_REQUIRED; }
030      @Override
031      public int numSpecializedScans() { return 1; }
032    }