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


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 import gov.nasa.jpf.util.CoverageManager;
25
26 import org.apache.bcel.classfile.ConstantPool;
27
28
29 /**
30  * DOCUMENT ME!
31  */
32 public class IFNULL extends IfInstruction {
33   private int target;
34
35   public void setPeer (org.apache.bcel.generic.Instruction i, ConstantPool cp) {
36     target = ((org.apache.bcel.generic.IFNULL) i).getTarget().getPosition();
37   }
38
39   public Instruction execute (SystemState ss, KernelState ks, ThreadInfo th) {
40     int v = th.pop();
41
42     if (v == -1) {
43       CoverageManager.incIFBranch(th.index, indexTrue);
44
45       return th.getMethod().getInstructionAt(target);
46     }
47
48     CoverageManager.incIFBranch(th.index, indexFalse);
49
50     return getNext(th);
51   }
52
53   public int getByteCode () {
54     return 0xC6;
55   }
56 }
57
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