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


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.JPFException;
22 import gov.nasa.jpf.jvm.ElementInfo;
23 import gov.nasa.jpf.jvm.KernelState;
24 import gov.nasa.jpf.jvm.SystemState;
25 import gov.nasa.jpf.jvm.ThreadInfo;
26 import gov.nasa.jpf.jvm.DynamicArea;
27
28 import gov.nasa.jpf.jvm.FieldInfo;
29
30
31 /**
32  * Set field in object
33  * ..., objectref, value => ...
34  */
35 public class PUTFIELD extends InstanceFieldInstruction implements StoreInstruction
36 {
37   public Instruction execute (SystemState ss, KernelState ks, ThreadInfo ti) {
38     FieldInfo fi = getFieldInfo();
39     long lvalue = 0;
40     int ivalue = 0;
41
42     // Hrmm, we can't encapsulate the size discrimination in ElementInfo, since
43 // we have to pop different data types before we ever get to it
44 switch (fi.getStorageSize()) {
45       case 1:
46         ivalue = ti.pop();
47         break;
48       case 2:
49         lvalue = ti.longPop();
50         break;
51       default:
52         throw new JPFException("invalid field type");
53     }
54     
55     int objRef = lastThis = ti.pop();
56     if (objRef == -1) {
57       return ti.createAndThrowException("java.lang.NullPointerException",
58                                  "referencing field '" + fname + "' on null object");
59     }
60
61     ElementInfo e = DynamicArea.getHeap().get(objRef);
62     if (fi.isReference()) {
63       e.setReferenceField(fi, ivalue);
64     } else {
65       if (size == 1) {
66         e.setIntField(fi, ivalue);
67       } else {
68         e.setLongField(fi, lvalue);
69       }
70     }
71     
72     return getNext(ti);
73   }
74
75   public int getByteCode () {
76     return 0xB5;
77   }
78   
79   public boolean isSchedulingRelevant (SystemState ss, KernelState ks, ThreadInfo ti) {
80     if (ti.usePorFieldBoundaries()) {
81       FieldInfo fi = getFieldInfo();
82       int objRef = ti.peek( (fi.getStorageSize() == 1) ? 1 : 2);
83
84       return isSchedulingRelevant(ks, ti, objRef);
85     }
86
87     return false;
88   }
89 }
90
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