/*

 * 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,

 * CA 95054 USA or visit www.sun.com if you need additional information or

 * have any questions.

 *

 */

package sun.jvm.hotspot.code;

import java.io.*;

import java.util.*;

import sun.jvm.hotspot.debugger.*;

import sun.jvm.hotspot.runtime.*;

import sun.jvm.hotspot.types.*;

/** PcDescs map a physical PC (given as offset from start of nmethod)

    to the corresponding source scope and byte code index. */

public class PCDesc extends VMObject {

  private static CIntegerField pcOffsetField;

  private static CIntegerField scopeDecodeOffsetField;

  static {

    VM.registerVMInitializedObserver(new Observer() {

        public void update(Observable o, Object data) {

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

        }

      });

  }

  private static void initialize(TypeDataBase db) {

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

    pcOffsetField          = type.getCIntegerField("_pc_offset");

    scopeDecodeOffsetField = type.getCIntegerField("_scope_decode_offset");

  }

  public PCDesc(Address addr) {

    super(addr);

  }

  // FIXME: add additional constructor probably needed for ScopeDesc::sender()

  public int getPCOffset() {

    return (int) pcOffsetField.getValue(addr);

  }

  public int getScopeDecodeOffset() {

    return ((int) scopeDecodeOffsetField.getValue(addr));

  }

  public Address getRealPC(NMethod code) {

    return code.instructionsBegin().addOffsetTo(getPCOffset());

  }

  public void print(NMethod code) {

    printOn(System.out, code);

  }

  public void printOn(PrintStream tty, NMethod code) {

    tty.println("PCDesc(" + getRealPC(code) + "):");

    for (ScopeDesc sd = code.getScopeDescAt(getRealPC(code));

         sd != null;

         sd = sd.sender()) {

      tty.print(" ");

      sd.getMethod().printValueOn(tty);

      tty.print("  @" + sd.getBCI());

      tty.print("  reexecute=" + sd.getReexecute());

      tty.println();

    }

  }

}