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1
30 package org.objectweb.asm.commons;
31
32 import java.util.HashMap  ;
33 import java.util.Map ;
34
35 import org.objectweb.asm.Label;
36 import org.objectweb.asm.MethodAdapter;
37 import org.objectweb.asm.MethodVisitor;
38 import org.objectweb.asm.Opcodes;
39 import org.objectweb.asm.Type;
40
41
50 public class LocalVariablesSorter extends MethodAdapter {
51
52 private Map locals = new HashMap ();
53
54 protected final int firstLocal;
55
56 private int nextLocal;
57
58 public LocalVariablesSorter(
59 final int access,
60 final String desc,
61 final MethodVisitor mv)
62 {
63 super(mv);
64 Type[] args = Type.getArgumentTypes(desc);
65 nextLocal = ((Opcodes.ACC_STATIC & access) != 0) ? 0 : 1;
66 for (int i = 0; i < args.length; i++) {
67 nextLocal += args[i].getSize();
68 }
69 firstLocal = nextLocal;
70 }
71
72 public void visitVarInsn(final int opcode, final int var) {
73 int size;
74 switch (opcode) {
75 case Opcodes.LLOAD:
76 case Opcodes.LSTORE:
77 case Opcodes.DLOAD:
78 case Opcodes.DSTORE:
79 size = 2;
80 break;
81 default:
82 size = 1;
83 }
84 mv.visitVarInsn(opcode, remap(var, size));
85 }
86
87 public void visitIincInsn(final int var, final int increment) {
88 mv.visitIincInsn(remap(var, 1), increment);
89 }
90
91 public void visitMaxs(final int maxStack, final int maxLocals) {
92 mv.visitMaxs(0, 0);
93 }
94
95 public void visitLocalVariable(
96 final String name,
97 final String desc,
98 final String signature,
99 final Label start,
100 final Label end,
101 final int index)
102 {
103 mv.visitLocalVariable(name, desc, signature, start, end, remap(index));
104 }
105
106
108 protected int newLocal(final int size) {
109 int var = nextLocal;
110 nextLocal += size;
111 return var;
112 }
113
114 private int remap(final int var, final int size) {
115 if (var < firstLocal) {
116 return var;
117 }
118 Integer key = new Integer (size == 2 ? ~var : var);
119 Integer value = (Integer ) locals.get(key);
120 if (value == null) {
121 value = new Integer (newLocal(size));
122 locals.put(key, value);
123 }
124 return value.intValue();
125 }
126
127 private int remap(final int var) {
128 if (var < firstLocal) {
129 return var;
130 }
131 Integer key = new Integer (var);
132 Integer value = (Integer ) locals.get(key);
133 if (value == null) {
134 key = new Integer (~var);
135 value = (Integer ) locals.get(key);
136 if (value == null) {
137 throw new IllegalStateException ("Unknown local variable " + var);
138 }
139 }
140 return value.intValue();
141 }
142 }
143 |
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