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 */
013package org.mmtk.plan.semispace;
014
015import org.mmtk.plan.*;
016import org.mmtk.policy.CopySpace;
017import org.vmmagic.pragma.*;
018
019/**
020 * SemiSpace common constants.
021 */
022@Uninterruptible
023public class SSConstraints extends StopTheWorldConstraints {
024  @Override
025  public boolean movesObjects() {
026    return true;
027  }
028  @Override
029  public int gcHeaderBits() {
030    return CopySpace.LOCAL_GC_BITS_REQUIRED;
031  }
032  @Override
033  public int gcHeaderWords() {
034    return CopySpace.GC_HEADER_WORDS_REQUIRED;
035  }
036  @Override
037  public int numSpecializedScans() {
038    return 1;
039  }
040}