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.stickyms;
014
015import org.mmtk.plan.marksweep.MSConstraints;
016
017import org.mmtk.policy.SegregatedFreeListSpace;
018
019import org.vmmagic.pragma.*;
020
021/**
022 * This class and its subclasses communicate to the host VM/Runtime
023 * any features of the selected plan that it needs to know.  This is
024 * separate from the main Plan/PlanLocal class in order to bypass any
025 * issues with ordering of static initialization.
026 */
027@Uninterruptible
028public class StickyMSConstraints extends MSConstraints {
029  /** @return The number of specialized scans.  We need nursery & full heap. */
030  @Override
031  public int numSpecializedScans() {
032    return 2;
033  }
034
035  @Override
036  public boolean needsObjectReferenceWriteBarrier() {
037    return true;
038  }
039
040  @Override
041  public boolean needsLogBitInHeader() {
042    return true;
043  }
044
045  @Override
046  public int maxNonLOSDefaultAllocBytes() {
047    return SegregatedFreeListSpace.MAX_FREELIST_OBJECT_BYTES;
048  }
049
050  @Override
051  public boolean objectReferenceBulkCopySupported() {
052    return true;
053  }
054}