/*

 * Copyright (c) 2007, 2015, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

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 *

 */

package sun.jvm.hotspot.gc.cms;

import java.io.*;

import java.util.*;

import sun.jvm.hotspot.debugger.*;

import sun.jvm.hotspot.runtime.*;

import sun.jvm.hotspot.types.*;

public class CMSCollector extends VMObject {

  private static long markBitMapFieldOffset;

  public CMSCollector(Address addr) {

    super(addr);

  }

  static {

    VM.registerVMInitializedObserver(new Observer() {

        public void update(Observable o, Object data) {

          initialize(VM.getVM().getTypeDataBase());

        }

      });

  }

  private static synchronized void initialize(TypeDataBase db) {

    Type type = db.lookupType("CMSCollector");

    markBitMapFieldOffset = type.getField("_markBitMap").getOffset();

  }

  //Accessing mark bitmap

  public CMSBitMap markBitMap() {

   return (CMSBitMap) VMObjectFactory.newObject(

                                CMSBitMap.class,

                                addr.addOffsetTo(markBitMapFieldOffset));

  }

  public long blockSizeUsingPrintezisBits(Address addr) {

    CMSBitMap markBitMap = markBitMap();

    long addressSize = VM.getVM().getAddressSize();

    if ( markBitMap.isMarked(addr) &&  markBitMap.isMarked(addr.addOffsetTo(1*addressSize)) ) {

      Address nextOneAddr = markBitMap.getNextMarkedWordAddress(addr.addOffsetTo(2*addressSize));

      //return size in bytes

      long size =  (nextOneAddr.addOffsetTo(1*addressSize)).minus(addr);

      return size;

    } else {

      //missing Printezis marks

      return -1;

    }

  }

}