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.refcount;
014
015import org.mmtk.plan.TransitiveClosure;
016
017import org.vmmagic.pragma.*;
018import org.vmmagic.unboxed.*;
019
020/**
021 * This class is the fundamental mechanism for performing a
022 * transitive closure over an object graph.
023 *
024 * @see org.mmtk.plan.TraceLocal
025 */
026@Uninterruptible
027public final class RCZero extends TransitiveClosure {
028
029  @Override
030  @Inline
031  public void processEdge(ObjectReference source, Address slot) {
032    slot.store(ObjectReference.nullReference());
033  }
034}
035