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16 package net.sf.cglib.core;
17
18 import org.objectweb.asm.*;
19 import java.util.*;
20
21 public class RemappingCodeVisitor extends CodeAdapter {
22 private State state;
23 private IntRef check = new IntRef();
24
25 private static class State {
26 Map locals = new HashMap();
27 int firstLocal;
28 int nextLocal;
29
30 State(int access, Type[] args) {
31 nextLocal = ((Constants.ACC_STATIC & access) != 0) ? 0 : 1;
32 for (int i = 0; i < args.length; i++) {
33 nextLocal += args[i].getSize();
34 }
35 firstLocal = nextLocal;
36 }
37 }
38
39 private static class IntRef {
40 int key;
41 public boolean equals(Object  o) {
42 return key == ((IntRef)o).key;
43 }
44 public int hashCode() {
45 return key;
46 }
47 }
48
49 public RemappingCodeVisitor(CodeVisitor v, int access, Type[] args) {
50 super(v);
51 state = new State(access, args);
52 }
53
54 public RemappingCodeVisitor(RemappingCodeVisitor wrap) {
55 super(wrap.cv);
56 this.state = wrap.state;
57 }
58
59 protected int nextLocal(int size) {
60 int var = state.nextLocal;
61 state.nextLocal += size;
62 return var;
63 }
64
65 private int remap(int var, int size) {
66 if (var < state.firstLocal) {
67 return var;
68 }
69 Integer value = remapHelper(var, (size == 0) ? 1 : size);
70 if (value == null) {
71 if (size == 0) {
72 value = remapHelper(var, 2);
73 if (value == null) {
74 throw new IllegalStateException ("Unknown local variable " + var);
75 }
76 } else {
77 IntRef ref = new IntRef();
78 ref.key = getKey(var, size);
79 state.locals.put(ref, value = new Integer (nextLocal(size)));
80 }
81 }
82 return value.intValue();
84 }
85
86 private Integer remapHelper(int var, int size) {
87 check.key = getKey(var, size);
88 return (Integer )state.locals.get(check);
89 }
90
91 private int getKey(int var, int size) {
92 return (size == 2) ? ~var : var;
93 }
94
95 public void visitIincInsn(int var, int increment) {
96 cv.visitIincInsn(remap(var, 1), increment);
97 }
98
99 public void visitLocalVariable(String name, String desc, Label start, Label end, int index) {
100 cv.visitLocalVariable(name, desc, start, end, remap(index, 0));
101 }
102
103 public void visitVarInsn(int opcode, int var) {
104 int size;
105 switch (opcode) {
106 case Constants.LLOAD:
107 case Constants.LSTORE:
108 case Constants.DLOAD:
109 case Constants.DSTORE:
110 size = 2;
111 break;
112 default:
113 size = 1;
114 }
115 cv.visitVarInsn(opcode, remap(var, size));
116 }
117
118 public void visitMaxs(int maxStack, int maxLocals) {
119 cv.visitMaxs(0, 0);
120 }
121 }
122
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