MarkSweepMarkBits.java

/*
 *  This file is part of the Jikes RVM project (http://jikesrvm.org).
 *
 *  This file is licensed to You under the Eclipse Public License (EPL);
 *  You may not use this file except in compliance with the License. You
 *  may obtain a copy of the License at
 *
 *      http://www.opensource.org/licenses/eclipse-1.0.php
 *
 *  See the COPYRIGHT.txt file distributed with this work for information
 *  regarding copyright ownership.
 */
package org.mmtk.utility.options;

import org.mmtk.policy.MarkSweepSpace;

/**
 * Number of bits to use for the header cycle of mark sweep spaces.
 */
public final class MarkSweepMarkBits extends org.vmutil.options.IntOption {
  /**
   * Create the option.
   */
  public MarkSweepMarkBits() {
    super(Options.set, "Mark Sweep Mark Bits",
          "Number of bits to use for the header cycle of mark sweep spaces",
          MarkSweepSpace.DEFAULT_MARKCOUNT_BITS);
  }

  /**
   * Ensure the value is valid.
   */
  protected void validate() {
    failIf(this.value <= 0, "Must provide at least one bit");
    failIf(this.value > MarkSweepSpace.MAX_MARKCOUNT_BITS , "Only "+MarkSweepSpace.MAX_MARKCOUNT_BITS+" bits are reserved in MarkSweepSpace");
  }
}