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.utility.options;
014    
015    import org.mmtk.policy.MarkSweepSpace;
016    
017    /**
018     * Number of bits to use for the header cycle of mark sweep spaces.
019     */
020    public final class MarkSweepMarkBits extends org.vmutil.options.IntOption {
021      /**
022       * Create the option.
023       */
024      public MarkSweepMarkBits() {
025        super(Options.set, "Mark Sweep Mark Bits",
026              "Number of bits to use for the header cycle of mark sweep spaces",
027              MarkSweepSpace.DEFAULT_MARKCOUNT_BITS);
028      }
029    
030      /**
031       * Ensure the value is valid.
032       */
033      @Override
034      protected void validate() {
035        failIf(this.value <= 0, "Must provide at least one bit");
036        failIf(this.value > MarkSweepSpace.MAX_MARKCOUNT_BITS , "Only "+MarkSweepSpace.MAX_MARKCOUNT_BITS+" bits are reserved in MarkSweepSpace");
037      }
038    }