/***
* ASM: a very small and fast Java bytecode manipulation framework
* Copyright (c) 2000-2005 INRIA, France Telecom
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the copyright holders nor the names of its
* contributors may be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
* THE POSSIBILITY OF SUCH DAMAGE.
*/
package ext.test4j.cglib.core;
import ext.test4j.asm.Label;
import ext.test4j.asm.MethodAdapter;
import ext.test4j.asm.MethodVisitor;
import ext.test4j.asm.Opcodes;
import ext.test4j.asm.Type;
/**
* A {@link MethodAdapter} that renumbers local variables in their order of
* appearance. This adapter allows one to easily add new local variables to a
* method.
*
* @author Chris Nokleberg
* @author Eric Bruneton
*/
public class LocalVariablesSorter extends MethodAdapter {
/**
* Mapping from old to new local variable indexes. A local variable at index
* i of size 1 is remapped to 'mapping[2*i]', while a local variable at
* index i of size 2 is remapped to 'mapping[2*i+1]'.
*/
private static class State {
int[] mapping = new int[40];
int nextLocal;
}
protected final int firstLocal;
private final State state;
public LocalVariablesSorter(final int access, final String desc, final MethodVisitor mv) {
super(mv);
state = new State();
Type[] args = Type.getArgumentTypes(desc);
state.nextLocal = ((Opcodes.ACC_STATIC & access) != 0) ? 0 : 1;
for (int i = 0; i < args.length; i++) {
state.nextLocal += args[i].getSize();
}
firstLocal = state.nextLocal;
}
public LocalVariablesSorter(LocalVariablesSorter lvs) {
super(lvs.mv);
state = lvs.state;
firstLocal = lvs.firstLocal;
}
public void visitVarInsn(final int opcode, final int var) {
int size;
switch (opcode) {
case Opcodes.LLOAD:
case Opcodes.LSTORE:
case Opcodes.DLOAD:
case Opcodes.DSTORE:
size = 2;
break;
default:
size = 1;
}
mv.visitVarInsn(opcode, remap(var, size));
}
public void visitIincInsn(final int var, final int increment) {
mv.visitIincInsn(remap(var, 1), increment);
}
public void visitMaxs(final int maxStack, final int maxLocals) {
mv.visitMaxs(maxStack, state.nextLocal);
}
public void visitLocalVariable(final String name, final String desc, final String signature, final Label start,
final Label end, final int index) {
mv.visitLocalVariable(name, desc, signature, start, end, remap(index));
}
// -------------
protected int newLocal(final int size) {
int var = state.nextLocal;
state.nextLocal += size;
return var;
}
private int remap(final int var, final int size) {
if (var < firstLocal) {
return var;
}
int key = 2 * var + size - 1;
int length = state.mapping.length;
if (key >= length) {
int[] newMapping = new int[Math.max(2 * length, key + 1)];
System.arraycopy(state.mapping, 0, newMapping, 0, length);
state.mapping = newMapping;
}
int value = state.mapping[key];
if (value == 0) {
value = state.nextLocal + 1;
state.mapping[key] = value;
state.nextLocal += size;
}
return value - 1;
}
private int remap(final int var) {
if (var < firstLocal) {
return var;
}
int key = 2 * var;
int value = key < state.mapping.length ? state.mapping[key] : 0;
if (value == 0) {
value = key + 1 < state.mapping.length ? state.mapping[key + 1] : 0;
}
if (value == 0) {
throw new IllegalStateException("Unknown local variable " + var);
}
return value - 1;
}
}