/***
* 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 clojure.asm.commons;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
import clojure.asm.ClassVisitor;
import clojure.asm.Label;
import clojure.asm.MethodVisitor;
import clojure.asm.Opcodes;
import clojure.asm.Type;
/**
* A {@link clojure.asm.MethodAdapter} with convenient methods to generate
* code. For example, using this adapter, the class below
* <p/>
* <pre>
* public class Example {
* public static void main(String[] args) {
* System.out.println("Hello world!");
* }
* }
* </pre>
* <p/>
* can be generated as follows:
* <p/>
* <pre>
* ClassWriter cw = new ClassWriter(true);
* cw.visit(V1_1, ACC_PUBLIC, "Example", null, "java/lang/Object", null);
* <p/>
* Method m = Method.getMethod("void <init> ()");
* GeneratorAdapter mg = new GeneratorAdapter(ACC_PUBLIC, m, null, null, cw);
* mg.loadThis();
* mg.invokeConstructor(Type.getType(Object.class), m);
* mg.returnValue();
* mg.endMethod();
* <p/>
* m = Method.getMethod("void main (String[])");
* mg = new GeneratorAdapter(ACC_PUBLIC + ACC_STATIC, m, null, null, cw);
* mg.getStatic(Type.getType(System.class), "out", Type.getType(PrintStream.class));
* mg.push("Hello world!");
* mg.invokeVirtual(Type.getType(PrintStream.class), Method.getMethod("void println (String)"));
* mg.returnValue();
* mg.endMethod();
* <p/>
* cw.visitEnd();
* </pre>
*
* @author Juozas Baliuka
* @author Chris Nokleberg
* @author Eric Bruneton
*/
public class GeneratorAdapter extends LocalVariablesSorter{
private final static Type BYTE_TYPE = Type.getObjectType("java/lang/Byte");
private final static Type BOOLEAN_TYPE = Type.getObjectType("java/lang/Boolean");
private final static Type SHORT_TYPE = Type.getObjectType("java/lang/Short");
private final static Type CHARACTER_TYPE = Type.getObjectType("java/lang/Character");
private final static Type INTEGER_TYPE = Type.getObjectType("java/lang/Integer");
private final static Type FLOAT_TYPE = Type.getObjectType("java/lang/Float");
private final static Type LONG_TYPE = Type.getObjectType("java/lang/Long");
private final static Type DOUBLE_TYPE = Type.getObjectType("java/lang/Double");
private final static Type NUMBER_TYPE = Type.getObjectType("java/lang/Number");
private final static Type OBJECT_TYPE = Type.getObjectType("java/lang/Object");
private final static Method BOOLEAN_VALUE = Method.getMethod("boolean booleanValue()");
private final static Method CHAR_VALUE = Method.getMethod("char charValue()");
private final static Method INT_VALUE = Method.getMethod("int intValue()");
private final static Method FLOAT_VALUE = Method.getMethod("float floatValue()");
private final static Method LONG_VALUE = Method.getMethod("long longValue()");
private final static Method DOUBLE_VALUE = Method.getMethod("double doubleValue()");
/**
* Constant for the {@link #math math} method.
*/
public final static int ADD = Opcodes.IADD;
/**
* Constant for the {@link #math math} method.
*/
public final static int SUB = Opcodes.ISUB;
/**
* Constant for the {@link #math math} method.
*/
public final static int MUL = Opcodes.IMUL;
/**
* Constant for the {@link #math math} method.
*/
public final static int DIV = Opcodes.IDIV;
/**
* Constant for the {@link #math math} method.
*/
public final static int REM = Opcodes.IREM;
/**
* Constant for the {@link #math math} method.
*/
public final static int NEG = Opcodes.INEG;
/**
* Constant for the {@link #math math} method.
*/
public final static int SHL = Opcodes.ISHL;
/**
* Constant for the {@link #math math} method.
*/
public final static int SHR = Opcodes.ISHR;
/**
* Constant for the {@link #math math} method.
*/
public final static int USHR = Opcodes.IUSHR;
/**
* Constant for the {@link #math math} method.
*/
public final static int AND = Opcodes.IAND;
/**
* Constant for the {@link #math math} method.
*/
public final static int OR = Opcodes.IOR;
/**
* Constant for the {@link #math math} method.
*/
public final static int XOR = Opcodes.IXOR;
/**
* Constant for the {@link #ifCmp ifCmp} method.
*/
public final static int EQ = Opcodes.IFEQ;
/**
* Constant for the {@link #ifCmp ifCmp} method.
*/
public final static int NE = Opcodes.IFNE;
/**
* Constant for the {@link #ifCmp ifCmp} method.
*/
public final static int LT = Opcodes.IFLT;
/**
* Constant for the {@link #ifCmp ifCmp} method.
*/
public final static int GE = Opcodes.IFGE;
/**
* Constant for the {@link #ifCmp ifCmp} method.
*/
public final static int GT = Opcodes.IFGT;
/**
* Constant for the {@link #ifCmp ifCmp} method.
*/
public final static int LE = Opcodes.IFLE;
/**
* Access flags of the method visited by this adapter.
*/
private final int access;
/**
* Return type of the method visited by this adapter.
*/
private final Type returnType;
/**
* Argument types of the method visited by this adapter.
*/
private final Type[] argumentTypes;
/**
* Types of the local variables of the method visited by this adapter.
*/
private final List localTypes = new ArrayList();
/**
* Creates a new {@link GeneratorAdapter}.
*
* @param mv the method visitor to which this adapter delegates calls.
* @param access the method's access flags (see {@link Opcodes}).
* @param name the method's name.
* @param desc the method's descriptor (see {@link Type Type}).
*/
public GeneratorAdapter(
final MethodVisitor mv,
final int access,
final String name,
final String desc){
super(access, desc, mv);
this.access = access;
this.returnType = Type.getReturnType(desc);
this.argumentTypes = Type.getArgumentTypes(desc);
}
/**
* Creates a new {@link GeneratorAdapter}.
*
* @param access access flags of the adapted method.
* @param method the adapted method.
* @param mv the method visitor to which this adapter delegates calls.
*/
public GeneratorAdapter(
final int access,
final Method method,
final MethodVisitor mv){
super(access, method.getDescriptor(), mv);
this.access = access;
this.returnType = method.getReturnType();
this.argumentTypes = method.getArgumentTypes();
}
/**
* Creates a new {@link GeneratorAdapter}.
*
* @param access access flags of the adapted method.
* @param method the adapted method.
* @param signature the signature of the adapted method (may be
* <tt>null</tt>).
* @param exceptions the exceptions thrown by the adapted method (may be
* <tt>null</tt>).
* @param cv the class visitor to which this adapter delegates calls.
*/
public GeneratorAdapter(
final int access,
final Method method,
final String signature,
final Type[] exceptions,
final ClassVisitor cv){
this(access, method, cv.visitMethod(access,
method.getName(),
method.getDescriptor(),
signature,
getInternalNames(exceptions)));
}
/**
* Returns the internal names of the given types.
*
* @param types a set of types.
* @return the internal names of the given types.
*/
private static String[] getInternalNames(final Type[] types){
if(types == null)
{
return null;
}
String[] names = new String[types.length];
for(int i = 0; i < names.length; ++i)
{
names[i] = types[i].getInternalName();
}
return names;
}
// ------------------------------------------------------------------------
// Instructions to push constants on the stack
// ------------------------------------------------------------------------
/**
* Generates the instruction to push the given value on the stack.
*
* @param value the value to be pushed on the stack.
*/
public void push(final boolean value){
push(value ? 1 : 0);
}
/**
* Generates the instruction to push the given value on the stack.
*
* @param value the value to be pushed on the stack.
*/
public void push(final int value){
if(value >= -1 && value <= 5)
{
mv.visitInsn(Opcodes.ICONST_0 + value);
}
else if(value >= Byte.MIN_VALUE && value <= Byte.MAX_VALUE)
{
mv.visitIntInsn(Opcodes.BIPUSH, value);
}
else if(value >= Short.MIN_VALUE && value <= Short.MAX_VALUE)
{
mv.visitIntInsn(Opcodes.SIPUSH, value);
}
else
{
mv.visitLdcInsn(new Integer(value));
}
}
/**
* Generates the instruction to push the given value on the stack.
*
* @param value the value to be pushed on the stack.
*/
public void push(final long value){
if(value == 0L || value == 1L)
{
mv.visitInsn(Opcodes.LCONST_0 + (int) value);
}
else
{
mv.visitLdcInsn(new Long(value));
}
}
/**
* Generates the instruction to push the given value on the stack.
*
* @param value the value to be pushed on the stack.
*/
public void push(final float value){
int bits = Float.floatToIntBits(value);
if(bits == 0L || bits == 0x3f800000 || bits == 0x40000000)
{ // 0..2
mv.visitInsn(Opcodes.FCONST_0 + (int) value);
}
else
{
mv.visitLdcInsn(new Float(value));
}
}
/**
* Generates the instruction to push the given value on the stack.
*
* @param value the value to be pushed on the stack.
*/
public void push(final double value){
long bits = Double.doubleToLongBits(value);
if(bits == 0L || bits == 0x3ff0000000000000L)
{ // +0.0d and 1.0d
mv.visitInsn(Opcodes.DCONST_0 + (int) value);
}
else
{
mv.visitLdcInsn(new Double(value));
}
}
/**
* Generates the instruction to push the given value on the stack.
*
* @param value the value to be pushed on the stack. May be <tt>null</tt>.
*/
public void push(final String value){
if(value == null)
{
mv.visitInsn(Opcodes.ACONST_NULL);
}
else
{
mv.visitLdcInsn(value);
}
}
/**
* Generates the instruction to push the given value on the stack.
*
* @param value the value to be pushed on the stack.
*/
public void push(final Type value){
if(value == null)
{
mv.visitInsn(Opcodes.ACONST_NULL);
}
else
{
mv.visitLdcInsn(value);
}
}
// ------------------------------------------------------------------------
// Instructions to load and store method arguments
// ------------------------------------------------------------------------
/**
* Returns the index of the given method argument in the frame's local
* variables array.
*
* @param arg the index of a method argument.
* @return the index of the given method argument in the frame's local
* variables array.
*/
private int getArgIndex(final int arg){
int index = (access & Opcodes.ACC_STATIC) == 0 ? 1 : 0;
for(int i = 0; i < arg; i++)
{
index += argumentTypes[i].getSize();
}
return index;
}
/**
* Generates the instruction to push a local variable on the stack.
*
* @param type the type of the local variable to be loaded.
* @param index an index in the frame's local variables array.
*/
private void loadInsn(final Type type, final int index){
mv.visitVarInsn(type.getOpcode(Opcodes.ILOAD), index);
}
/**
* Generates the instruction to store the top stack value in a local
* variable.
*
* @param type the type of the local variable to be stored.
* @param index an index in the frame's local variables array.
*/
private void storeInsn(final Type type, final int index){
mv.visitVarInsn(type.getOpcode(Opcodes.ISTORE), index);
}
/**
* Generates the instruction to load 'this' on the stack.
*/
public void loadThis(){
if((access & Opcodes.ACC_STATIC) != 0)
{
throw new IllegalStateException("no 'this' pointer within static method");
}
mv.visitVarInsn(Opcodes.ALOAD, 0);
}
/**
* Generates the instruction to load the given method argument on the stack.
*
* @param arg the index of a method argument.
*/
public void loadArg(final int arg){
loadInsn(argumentTypes[arg], getArgIndex(arg));
}
/**
* Generates the instructions to load the given method arguments on the
* stack.
*
* @param arg the index of the first method argument to be loaded.
* @param count the number of method arguments to be loaded.
*/
public void loadArgs(final int arg, final int count){
int index = getArgIndex(arg);
for(int i = 0; i < count; ++i)
{
Type t = argumentTypes[arg + i];
loadInsn(t, index);
index += t.getSize();
}
}
/**
* Generates the instructions to load all the method arguments on the stack.
*/
public void loadArgs(){
loadArgs(0, argumentTypes.length);
}
/**
* Generates the instructions to load all the method arguments on the stack,
* as a single object array.
*/
public void loadArgArray(){
push(argumentTypes.length);
newArray(OBJECT_TYPE);
for(int i = 0; i < argumentTypes.length; i++)
{
dup();
push(i);
loadArg(i);
box(argumentTypes[i]);
arrayStore(OBJECT_TYPE);
}
}
/**
* Generates the instruction to store the top stack value in the given
* method argument.
*
* @param arg the index of a method argument.
*/
public void storeArg(final int arg){
storeInsn(argumentTypes[arg], getArgIndex(arg));
}
// ------------------------------------------------------------------------
// Instructions to load and store local variables
// ------------------------------------------------------------------------
/**
* Returns the type of the given local variable.
*
* @param local a local variable identifier, as returned by
* {@link LocalVariablesSorter#newLocal(Type) newLocal()}.
* @return the type of the given local variable.
*/
public Type getLocalType(final int local){
return (Type) localTypes.get(local - firstLocal);
}
protected void setLocalType(final int local, final Type type){
int index = local - firstLocal;
while(localTypes.size() < index + 1)
{
localTypes.add(null);
}
localTypes.set(index, type);
}
/**
* Generates the instruction to load the given local variable on the stack.
*
* @param local a local variable identifier, as returned by
* {@link LocalVariablesSorter#newLocal(Type) newLocal()}.
*/
public void loadLocal(final int local){
loadInsn(getLocalType(local), local);
}
/**
* Generates the instruction to load the given local variable on the stack.
*
* @param local a local variable identifier, as returned by
* {@link LocalVariablesSorter#newLocal(Type) newLocal()}.
* @param type the type of this local variable.
*/
public void loadLocal(final int local, final Type type){
setLocalType(local, type);
loadInsn(type, local);
}
/**
* Generates the instruction to store the top stack value in the given local
* variable.
*
* @param local a local variable identifier, as returned by
* {@link LocalVariablesSorter#newLocal(Type) newLocal()}.
*/
public void storeLocal(final int local){
storeInsn(getLocalType(local), local);
}
/**
* Generates the instruction to store the top stack value in the given local
* variable.
*
* @param local a local variable identifier, as returned by
* {@link LocalVariablesSorter#newLocal(Type) newLocal()}.
* @param type the type of this local variable.
*/
public void storeLocal(final int local, final Type type){
setLocalType(local, type);
storeInsn(type, local);
}
/**
* Generates the instruction to load an element from an array.
*
* @param type the type of the array element to be loaded.
*/
public void arrayLoad(final Type type){
mv.visitInsn(type.getOpcode(Opcodes.IALOAD));
}
/**
* Generates the instruction to store an element in an array.
*
* @param type the type of the array element to be stored.
*/
public void arrayStore(final Type type){
mv.visitInsn(type.getOpcode(Opcodes.IASTORE));
}
// ------------------------------------------------------------------------
// Instructions to manage the stack
// ------------------------------------------------------------------------
/**
* Generates a POP instruction.
*/
public void pop(){
mv.visitInsn(Opcodes.POP);
}
/**
* Generates a POP2 instruction.
*/
public void pop2(){
mv.visitInsn(Opcodes.POP2);
}
/**
* Generates a DUP instruction.
*/
public void dup(){
mv.visitInsn(Opcodes.DUP);
}
/**
* Generates a DUP2 instruction.
*/
public void dup2(){
mv.visitInsn(Opcodes.DUP2);
}
/**
* Generates a DUP_X1 instruction.
*/
public void dupX1(){
mv.visitInsn(Opcodes.DUP_X1);
}
/**
* Generates a DUP_X2 instruction.
*/
public void dupX2(){
mv.visitInsn(Opcodes.DUP_X2);
}
/**
* Generates a DUP2_X1 instruction.
*/
public void dup2X1(){
mv.visitInsn(Opcodes.DUP2_X1);
}
/**
* Generates a DUP2_X2 instruction.
*/
public void dup2X2(){
mv.visitInsn(Opcodes.DUP2_X2);
}
/**
* Generates a SWAP instruction.
*/
public void swap(){
mv.visitInsn(Opcodes.SWAP);
}
/**
* Generates the instructions to swap the top two stack values.
*
* @param prev type of the top - 1 stack value.
* @param type type of the top stack value.
*/
public void swap(final Type prev, final Type type){
if(type.getSize() == 1)
{
if(prev.getSize() == 1)
{
swap(); // same as dupX1(), pop();
}
else
{
dupX2();
pop();
}
}
else
{
if(prev.getSize() == 1)
{
dup2X1();
pop2();
}
else
{
dup2X2();
pop2();
}
}
}
// ------------------------------------------------------------------------
// Instructions to do mathematical and logical operations
// ------------------------------------------------------------------------
/**
* Generates the instruction to do the specified mathematical or logical
* operation.
*
* @param op a mathematical or logical operation. Must be one of ADD, SUB,
* MUL, DIV, REM, NEG, SHL, SHR, USHR, AND, OR, XOR.
* @param type the type of the operand(s) for this operation.
*/
public void math(final int op, final Type type){
mv.visitInsn(type.getOpcode(op));
}
/**
* Generates the instructions to compute the bitwise negation of the top
* stack value.
*/
public void not(){
mv.visitInsn(Opcodes.ICONST_1);
mv.visitInsn(Opcodes.IXOR);
}
/**
* Generates the instruction to increment the given local variable.
*
* @param local the local variable to be incremented.
* @param amount the amount by which the local variable must be incremented.
*/
public void iinc(final int local, final int amount){
mv.visitIincInsn(local, amount);
}
/**
* Generates the instructions to cast a numerical value from one type to
* another.
*
* @param from the type of the top stack value
* @param to the type into which this value must be cast.
*/
public void cast(final Type from, final Type to){
if(from != to)
{
if(from == Type.DOUBLE_TYPE)
{
if(to == Type.FLOAT_TYPE)
{
mv.visitInsn(Opcodes.D2F);
}
else if(to == Type.LONG_TYPE)
{
mv.visitInsn(Opcodes.D2L);
}
else
{
mv.visitInsn(Opcodes.D2I);
cast(Type.INT_TYPE, to);
}
}
else if(from == Type.FLOAT_TYPE)
{
if(to == Type.DOUBLE_TYPE)
{
mv.visitInsn(Opcodes.F2D);
}
else if(to == Type.LONG_TYPE)
{
mv.visitInsn(Opcodes.F2L);
}
else
{
mv.visitInsn(Opcodes.F2I);
cast(Type.INT_TYPE, to);
}
}
else if(from == Type.LONG_TYPE)
{
if(to == Type.DOUBLE_TYPE)
{
mv.visitInsn(Opcodes.L2D);
}
else if(to == Type.FLOAT_TYPE)
{
mv.visitInsn(Opcodes.L2F);
}
else
{
mv.visitInsn(Opcodes.L2I);
cast(Type.INT_TYPE, to);
}
}
else
{
if(to == Type.BYTE_TYPE)
{
mv.visitInsn(Opcodes.I2B);
}
else if(to == Type.CHAR_TYPE)
{
mv.visitInsn(Opcodes.I2C);
}
else if(to == Type.DOUBLE_TYPE)
{
mv.visitInsn(Opcodes.I2D);
}
else if(to == Type.FLOAT_TYPE)
{
mv.visitInsn(Opcodes.I2F);
}
else if(to == Type.LONG_TYPE)
{
mv.visitInsn(Opcodes.I2L);
}
else if(to == Type.SHORT_TYPE)
{
mv.visitInsn(Opcodes.I2S);
}
}
}
}
// ------------------------------------------------------------------------
// Instructions to do boxing and unboxing operations
// ------------------------------------------------------------------------
/**
* Generates the instructions to box the top stack value. This value is
* replaced by its boxed equivalent on top of the stack.
*
* @param type the type of the top stack value.
*/
public void box(final Type type){
if(type.getSort() == Type.OBJECT || type.getSort() == Type.ARRAY)
{
return;
}
if(type == Type.VOID_TYPE)
{
push((String) null);
}
else
{
Type boxed = type;
switch(type.getSort())
{
case Type.BYTE:
boxed = BYTE_TYPE;
break;
case Type.BOOLEAN:
boxed = BOOLEAN_TYPE;
break;
case Type.SHORT:
boxed = SHORT_TYPE;
break;
case Type.CHAR:
boxed = CHARACTER_TYPE;
break;
case Type.INT:
boxed = INTEGER_TYPE;
break;
case Type.FLOAT:
boxed = FLOAT_TYPE;
break;
case Type.LONG:
boxed = LONG_TYPE;
break;
case Type.DOUBLE:
boxed = DOUBLE_TYPE;
break;
}
newInstance(boxed);
if(type.getSize() == 2)
{
// Pp -> Ppo -> oPpo -> ooPpo -> ooPp -> o
dupX2();
dupX2();
pop();
}
else
{
// p -> po -> opo -> oop -> o
dupX1();
swap();
}
invokeConstructor(boxed, new Method("<init>",
Type.VOID_TYPE,
new Type[]{type}));
}
}
/**
* Generates the instructions to unbox the top stack value. This value is
* replaced by its unboxed equivalent on top of the stack.
*
* @param type the type of the top stack value.
*/
public void unbox(final Type type){
Type t = NUMBER_TYPE;
Method sig = null;
switch(type.getSort())
{
case Type.VOID:
return;
case Type.CHAR:
t = CHARACTER_TYPE;
sig = CHAR_VALUE;
break;
case Type.BOOLEAN:
t = BOOLEAN_TYPE;
sig = BOOLEAN_VALUE;
break;
case Type.DOUBLE:
sig = DOUBLE_VALUE;
break;
case Type.FLOAT:
sig = FLOAT_VALUE;
break;
case Type.LONG:
sig = LONG_VALUE;
break;
case Type.INT:
case Type.SHORT:
case Type.BYTE:
sig = INT_VALUE;
}
if(sig == null)
{
checkCast(type);
}
else
{
checkCast(t);
invokeVirtual(t, sig);
}
}
// ------------------------------------------------------------------------
// Instructions to jump to other instructions
// ------------------------------------------------------------------------
/**
* Creates a new {@link Label}.
*
* @return a new {@link Label}.
*/
public Label newLabel(){
return new Label();
}
/**
* Marks the current code position with the given label.
*
* @param label a label.
*/
public void mark(final Label label){
mv.visitLabel(label);
}
/**
* Marks the current code position with a new label.
*
* @return the label that was created to mark the current code position.
*/
public Label mark(){
Label label = new Label();
mv.visitLabel(label);
return label;
}
/**
* Generates the instructions to jump to a label based on the comparison of
* the top two stack values.
*
* @param type the type of the top two stack values.
* @param mode how these values must be compared. One of EQ, NE, LT, GE, GT,
* LE.
* @param label where to jump if the comparison result is <tt>true</tt>.
*/
public void ifCmp(final Type type, final int mode, final Label label){
int intOp = -1;
switch(type.getSort())
{
case Type.LONG:
mv.visitInsn(Opcodes.LCMP);
break;
case Type.DOUBLE:
mv.visitInsn(Opcodes.DCMPG);
break;
case Type.FLOAT:
mv.visitInsn(Opcodes.FCMPG);
break;
case Type.ARRAY:
case Type.OBJECT:
switch(mode)
{
case EQ:
mv.visitJumpInsn(Opcodes.IF_ACMPEQ, label);
return;
case NE:
mv.visitJumpInsn(Opcodes.IF_ACMPNE, label);
return;
}
throw new IllegalArgumentException("Bad comparison for type "
+ type);
default:
switch(mode)
{
case EQ:
intOp = Opcodes.IF_ICMPEQ;
break;
case NE:
intOp = Opcodes.IF_ICMPNE;
break;
case GE:
intOp = Opcodes.IF_ICMPGE;
break;
case LT:
intOp = Opcodes.IF_ICMPLT;
break;
case LE:
intOp = Opcodes.IF_ICMPLE;
break;
case GT:
intOp = Opcodes.IF_ICMPGT;
break;
}
mv.visitJumpInsn(intOp, label);
return;
}
int jumpMode = mode;
switch(mode)
{
case GE:
jumpMode = LT;
break;
case LE:
jumpMode = GT;
break;
}
mv.visitJumpInsn(jumpMode, label);
}
/**
* Generates the instructions to jump to a label based on the comparison of
* the top two integer stack values.
*
* @param mode how these values must be compared. One of EQ, NE, LT, GE, GT,
* LE.
* @param label where to jump if the comparison result is <tt>true</tt>.
*/
public void ifICmp(final int mode, final Label label){
ifCmp(Type.INT_TYPE, mode, label);
}
/**
* Generates the instructions to jump to a label based on the comparison of
* the top integer stack value with zero.
*
* @param mode how these values must be compared. One of EQ, NE, LT, GE, GT,
* LE.
* @param label where to jump if the comparison result is <tt>true</tt>.
*/
public void ifZCmp(final int mode, final Label label){
mv.visitJumpInsn(mode, label);
}
/**
* Generates the instruction to jump to the given label if the top stack
* value is null.
*
* @param label where to jump if the condition is <tt>true</tt>.
*/
public void ifNull(final Label label){
mv.visitJumpInsn(Opcodes.IFNULL, label);
}
/**
* Generates the instruction to jump to the given label if the top stack
* value is not null.
*
* @param label where to jump if the condition is <tt>true</tt>.
*/
public void ifNonNull(final Label label){
mv.visitJumpInsn(Opcodes.IFNONNULL, label);
}
/**
* Generates the instruction to jump to the given label.
*
* @param label where to jump if the condition is <tt>true</tt>.
*/
public void goTo(final Label label){
mv.visitJumpInsn(Opcodes.GOTO, label);
}
/**
* Generates a RET instruction.
*
* @param local a local variable identifier, as returned by
* {@link LocalVariablesSorter#newLocal(Type) newLocal()}.
*/
public void ret(final int local){
mv.visitVarInsn(Opcodes.RET, local);
}
/**
* Generates the instructions for a switch statement.
*
* @param keys the switch case keys.
* @param generator a generator to generate the code for the switch cases.
*/
public void tableSwitch(
final int[] keys,
final TableSwitchGenerator generator){
float density;
if(keys.length == 0)
{
density = 0;
}
else
{
density = (float) keys.length
/ (keys[keys.length - 1] - keys[0] + 1);
}
tableSwitch(keys, generator, density >= 0.5f);
}
/**
* Generates the instructions for a switch statement.
*
* @param keys the switch case keys.
* @param generator a generator to generate the code for the switch cases.
* @param useTable <tt>true</tt> to use a TABLESWITCH instruction, or
* <tt>false</tt> to use a LOOKUPSWITCH instruction.
*/
public void tableSwitch(
final int[] keys,
final TableSwitchGenerator generator,
final boolean useTable){
for(int i = 1; i < keys.length; ++i)
{
if(keys[i] < keys[i - 1])
{
throw new IllegalArgumentException("keys must be sorted ascending");
}
}
Label def = newLabel();
Label end = newLabel();
if(keys.length > 0)
{
int len = keys.length;
int min = keys[0];
int max = keys[len - 1];
int range = max - min + 1;
if(useTable)
{
Label[] labels = new Label[range];
Arrays.fill(labels, def);
for(int i = 0; i < len; ++i)
{
labels[keys[i] - min] = newLabel();
}
mv.visitTableSwitchInsn(min, max, def, labels);
for(int i = 0; i < range; ++i)
{
Label label = labels[i];
if(label != def)
{
mark(label);
generator.generateCase(i + min, end);
}
}
}
else
{
Label[] labels = new Label[len];
for(int i = 0; i < len; ++i)
{
labels[i] = newLabel();
}
mv.visitLookupSwitchInsn(def, keys, labels);
for(int i = 0; i < len; ++i)
{
mark(labels[i]);
generator.generateCase(keys[i], end);
}
}
}
mark(def);
generator.generateDefault();
mark(end);
}
/**
* Generates the instruction to return the top stack value to the caller.
*/
public void returnValue(){
mv.visitInsn(returnType.getOpcode(Opcodes.IRETURN));
}
// ------------------------------------------------------------------------
// Instructions to load and store fields
// ------------------------------------------------------------------------
/**
* Generates a get field or set field instruction.
*
* @param opcode the instruction's opcode.
* @param ownerType the class in which the field is defined.
* @param name the name of the field.
* @param fieldType the type of the field.
*/
private void fieldInsn(
final int opcode,
final Type ownerType,
final String name,
final Type fieldType){
mv.visitFieldInsn(opcode,
ownerType.getInternalName(),
name,
fieldType.getDescriptor());
}
/**
* Generates the instruction to push the value of a static field on the
* stack.
*
* @param owner the class in which the field is defined.
* @param name the name of the field.
* @param type the type of the field.
*/
public void getStatic(final Type owner, final String name, final Type type){
fieldInsn(Opcodes.GETSTATIC, owner, name, type);
}
/**
* Generates the instruction to store the top stack value in a static field.
*
* @param owner the class in which the field is defined.
* @param name the name of the field.
* @param type the type of the field.
*/
public void putStatic(final Type owner, final String name, final Type type){
fieldInsn(Opcodes.PUTSTATIC, owner, name, type);
}
/**
* Generates the instruction to push the value of a non static field on the
* stack.
*
* @param owner the class in which the field is defined.
* @param name the name of the field.
* @param type the type of the field.
*/
public void getField(final Type owner, final String name, final Type type){
fieldInsn(Opcodes.GETFIELD, owner, name, type);
}
/**
* Generates the instruction to store the top stack value in a non static
* field.
*
* @param owner the class in which the field is defined.
* @param name the name of the field.
* @param type the type of the field.
*/
public void putField(final Type owner, final String name, final Type type){
fieldInsn(Opcodes.PUTFIELD, owner, name, type);
}
// ------------------------------------------------------------------------
// Instructions to invoke methods
// ------------------------------------------------------------------------
/**
* Generates an invoke method instruction.
*
* @param opcode the instruction's opcode.
* @param type the class in which the method is defined.
* @param method the method to be invoked.
*/
private void invokeInsn(
final int opcode,
final Type type,
final Method method){
String owner = type.getSort() == Type.ARRAY
? type.getDescriptor()
: type.getInternalName();
mv.visitMethodInsn(opcode,
owner,
method.getName(),
method.getDescriptor());
}
/**
* Generates the instruction to invoke a normal method.
*
* @param owner the class in which the method is defined.
* @param method the method to be invoked.
*/
public void invokeVirtual(final Type owner, final Method method){
invokeInsn(Opcodes.INVOKEVIRTUAL, owner, method);
}
/**
* Generates the instruction to invoke a constructor.
*
* @param type the class in which the constructor is defined.
* @param method the constructor to be invoked.
*/
public void invokeConstructor(final Type type, final Method method){
invokeInsn(Opcodes.INVOKESPECIAL, type, method);
}
/**
* Generates the instruction to invoke a static method.
*
* @param owner the class in which the method is defined.
* @param method the method to be invoked.
*/
public void invokeStatic(final Type owner, final Method method){
invokeInsn(Opcodes.INVOKESTATIC, owner, method);
}
/**
* Generates the instruction to invoke an interface method.
*
* @param owner the class in which the method is defined.
* @param method the method to be invoked.
*/
public void invokeInterface(final Type owner, final Method method){
invokeInsn(Opcodes.INVOKEINTERFACE, owner, method);
}
// ------------------------------------------------------------------------
// Instructions to create objects and arrays
// ------------------------------------------------------------------------
/**
* Generates a type dependent instruction.
*
* @param opcode the instruction's opcode.
* @param type the instruction's operand.
*/
private void typeInsn(final int opcode, final Type type){
String desc;
if(type.getSort() == Type.ARRAY)
{
desc = type.getDescriptor();
}
else
{
desc = type.getInternalName();
}
mv.visitTypeInsn(opcode, desc);
}
/**
* Generates the instruction to create a new object.
*
* @param type the class of the object to be created.
*/
public void newInstance(final Type type){
typeInsn(Opcodes.NEW, type);
}
/**
* Generates the instruction to create a new array.
*
* @param type the type of the array elements.
*/
public void newArray(final Type type){
int typ;
switch(type.getSort())
{
case Type.BOOLEAN:
typ = Opcodes.T_BOOLEAN;
break;
case Type.CHAR:
typ = Opcodes.T_CHAR;
break;
case Type.BYTE:
typ = Opcodes.T_BYTE;
break;
case Type.SHORT:
typ = Opcodes.T_SHORT;
break;
case Type.INT:
typ = Opcodes.T_INT;
break;
case Type.FLOAT:
typ = Opcodes.T_FLOAT;
break;
case Type.LONG:
typ = Opcodes.T_LONG;
break;
case Type.DOUBLE:
typ = Opcodes.T_DOUBLE;
break;
default:
typeInsn(Opcodes.ANEWARRAY, type);
return;
}
mv.visitIntInsn(Opcodes.NEWARRAY, typ);
}
// ------------------------------------------------------------------------
// Miscelaneous instructions
// ------------------------------------------------------------------------
/**
* Generates the instruction to compute the length of an array.
*/
public void arrayLength(){
mv.visitInsn(Opcodes.ARRAYLENGTH);
}
/**
* Generates the instruction to throw an exception.
*/
public void throwException(){
mv.visitInsn(Opcodes.ATHROW);
}
/**
* Generates the instructions to create and throw an exception. The
* exception class must have a constructor with a single String argument.
*
* @param type the class of the exception to be thrown.
* @param msg the detailed message of the exception.
*/
public void throwException(final Type type, final String msg){
newInstance(type);
dup();
push(msg);
invokeConstructor(type, Method.getMethod("void <init> (String)"));
throwException();
}
/**
* Generates the instruction to check that the top stack value is of the
* given type.
*
* @param type a class or interface type.
*/
public void checkCast(final Type type){
if(!type.equals(OBJECT_TYPE))
{
typeInsn(Opcodes.CHECKCAST, type);
}
}
/**
* Generates the instruction to test if the top stack value is of the given
* type.
*
* @param type a class or interface type.
*/
public void instanceOf(final Type type){
typeInsn(Opcodes.INSTANCEOF, type);
}
/**
* Generates the instruction to get the monitor of the top stack value.
*/
public void monitorEnter(){
mv.visitInsn(Opcodes.MONITORENTER);
}
/**
* Generates the instruction to release the monitor of the top stack value.
*/
public void monitorExit(){
mv.visitInsn(Opcodes.MONITOREXIT);
}
// ------------------------------------------------------------------------
// Non instructions
// ------------------------------------------------------------------------
/**
* Marks the end of the visited method.
*/
public void endMethod(){
if((access & Opcodes.ACC_ABSTRACT) == 0)
{
mv.visitMaxs(0, 0);
}
mv.visitEnd();
}
/**
* Marks the start of an exception handler.
*
* @param start beginning of the exception handler's scope (inclusive).
* @param end end of the exception handler's scope (exclusive).
* @param exception internal name of the type of exceptions handled by the
* handler.
*/
public void catchException(
final Label start,
final Label end,
final Type exception){
mv.visitTryCatchBlock(start, end, mark(), exception.getInternalName());
}
}