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Java > Open Source Codes > gov > nasa > jpf > jvm > bytecode > MONITOREXIT


1 //
2 // Copyright (C) 2005 United States Government as represented by the
3 // Administrator of the National Aeronautics and Space Administration
4 // (NASA). All Rights Reserved.
5 //
6 // This software is distributed under the NASA Open Source Agreement
7 // (NOSA), version 1.3. The NOSA has been approved by the Open Source
8 // Initiative. See the file NOSA-1.3-JPF at the top of the distribution
9 // directory tree for the complete NOSA document.
10 //
11 // THE SUBJECT SOFTWARE IS PROVIDED "AS IS" WITHOUT ANY WARRANTY OF ANY
12 // KIND, EITHER EXPRESSED, IMPLIED, OR STATUTORY, INCLUDING, BUT NOT
13 // LIMITED TO, ANY WARRANTY THAT THE SUBJECT SOFTWARE WILL CONFORM TO
14 // SPECIFICATIONS, ANY IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR
15 // A PARTICULAR PURPOSE, OR FREEDOM FROM INFRINGEMENT, ANY WARRANTY THAT
16 // THE SUBJECT SOFTWARE WILL BE ERROR FREE, OR ANY WARRANTY THAT
17 // DOCUMENTATION, IF PROVIDED, WILL CONFORM TO THE SUBJECT SOFTWARE.
18 //
19 package gov.nasa.jpf.jvm.bytecode;
20
21 import gov.nasa.jpf.jvm.KernelState;
22 import gov.nasa.jpf.jvm.SystemState;
23 import gov.nasa.jpf.jvm.ThreadInfo;
24
25 import org.apache.bcel.classfile.ConstantPool;
26 import gov.nasa.jpf.jvm.ElementInfo;
27
28
29 /**
30  * Exit monitor for object
31  * ..., objectref => ...
32  */
33 public class MONITOREXIT extends Instruction {
34   public void setPeer (org.apache.bcel.generic.Instruction i, ConstantPool cp) {
35   }
36
37   public Instruction execute (SystemState ss, KernelState ks, ThreadInfo th) {
38     int objref = th.pop();
39
40     ks.da.get(objref).unlock(th);
41
42     return getNext(th);
43   }
44
45   public boolean isSchedulingRelevant (SystemState ss, KernelState ks, ThreadInfo ti) {
46     int objref = ti.peek();
47     ElementInfo ei = ks.da.get(objref);
48     
49     if (mi.isBodySchedulingRelevant(ti,ei) && (ei.getLockCount() == 1)) {
50       // only relevant if there are other runnables
51 return ti.hasOtherRunnables();
52     } else {
53       // recursive lock, not relevant
54 return false;
55     }
56   }
57
58   public int getByteCode () {
59     return 0xC3;
60   }
61 }
62
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