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	/*
	* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
	*
	* This code is free software; you can redistribute it and/or modify it
	* under the terms of the GNU General Public License version 2 only, as
	* published by the Free Software Foundation. Oracle designates this
	* particular file as subject to the "Classpath" exception as provided
	* by Oracle in the LICENSE file that accompanied this code.
	*
	* This code is distributed in the hope that it will be useful, but WITHOUT
	* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
	* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
	* version 2 for more details (a copy is included in the LICENSE file that
	* accompanied this code).
	*
	* You should have received a copy of the GNU General Public License version
	* 2 along with this work; if not, write to the Free Software Foundation,
	* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
	*
	* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
	* or visit www.oracle.com if you need additional information or have any
	* questions.
	*/

	/*
	* This file is available under and governed by the GNU General Public
	* License version 2 only, as published by the Free Software Foundation.
	* However, the following notice accompanied the original version of this
	* file:
	*
	* ASM: a very small and fast Java bytecode manipulation framework
	* Copyright (c) 2000-2011 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 jdk.internal.org.objectweb.asm.commons;

	import java.util.ArrayList;
	import java.util.Arrays;
	import java.util.List;

	import jdk.internal.org.objectweb.asm.ClassVisitor;
	import jdk.internal.org.objectweb.asm.Handle;
	import jdk.internal.org.objectweb.asm.Label;
	import jdk.internal.org.objectweb.asm.MethodVisitor;
	import jdk.internal.org.objectweb.asm.Opcodes;
	import jdk.internal.org.objectweb.asm.Type;

	/**
	* A {@link jdk.internal.org.objectweb.asm.MethodVisitor} with convenient methods to generate
	* code. For example, using this adapter, the class below
	*
	* <pre>
	* public class Example {
	* public static void main(String[] args) {
	* System.out.println("Hello world!");
	* }
	* }
	* </pre>
	*
	* can be generated as follows:
	*
	* <pre>
	* ClassWriter cw = new ClassWriter(true);
	* cw.visit(V1_1, ACC_PUBLIC, "Example", null, "java/lang/Object", null);
	*
	* 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();
	*
	* 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();
	*
	* cw.visitEnd();
	* </pre>
	*
	* @author Juozas Baliuka
	* @author Chris Nokleberg
	* @author Eric Bruneton
	* @author Prashant Deva
	*/
	public class GeneratorAdapter extends LocalVariablesSorter {

	private static final String CLDESC = "Ljava/lang/Class;";

	private static final Type BYTE_TYPE = Type.getObjectType("java/lang/Byte");

	private static final Type BOOLEAN_TYPE = Type
	.getObjectType("java/lang/Boolean");

	private static final Type SHORT_TYPE = Type
	.getObjectType("java/lang/Short");

	private static final Type CHARACTER_TYPE = Type
	.getObjectType("java/lang/Character");

	private static final Type INTEGER_TYPE = Type
	.getObjectType("java/lang/Integer");

	private static final Type FLOAT_TYPE = Type
	.getObjectType("java/lang/Float");

	private static final Type LONG_TYPE = Type.getObjectType("java/lang/Long");

	private static final Type DOUBLE_TYPE = Type
	.getObjectType("java/lang/Double");

	private static final Type NUMBER_TYPE = Type
	.getObjectType("java/lang/Number");

	private static final Type OBJECT_TYPE = Type
	.getObjectType("java/lang/Object");

	private static final Method BOOLEAN_VALUE = Method
	.getMethod("boolean booleanValue()");

	private static final Method CHAR_VALUE = Method
	.getMethod("char charValue()");

	private static final Method INT_VALUE = Method.getMethod("int intValue()");

	private static final Method FLOAT_VALUE = Method
	.getMethod("float floatValue()");

	private static final Method LONG_VALUE = Method
	.getMethod("long longValue()");

	private static final Method DOUBLE_VALUE = Method
	.getMethod("double doubleValue()");

	/**
	* Constant for the {@link #math math} method.
	*/
	public static final int ADD = Opcodes.IADD;

	/**
	* Constant for the {@link #math math} method.
	*/
	public static final int SUB = Opcodes.ISUB;

	/**
	* Constant for the {@link #math math} method.
	*/
	public static final int MUL = Opcodes.IMUL;

	/**
	* Constant for the {@link #math math} method.
	*/
	public static final int DIV = Opcodes.IDIV;

	/**
	* Constant for the {@link #math math} method.
	*/
	public static final int REM = Opcodes.IREM;

	/**
	* Constant for the {@link #math math} method.
	*/
	public static final int NEG = Opcodes.INEG;

	/**
	* Constant for the {@link #math math} method.
	*/
	public static final int SHL = Opcodes.ISHL;

	/**
	* Constant for the {@link #math math} method.
	*/
	public static final int SHR = Opcodes.ISHR;

	/**
	* Constant for the {@link #math math} method.
	*/
	public static final int USHR = Opcodes.IUSHR;

	/**
	* Constant for the {@link #math math} method.
	*/
	public static final int AND = Opcodes.IAND;

	/**
	* Constant for the {@link #math math} method.
	*/
	public static final int OR = Opcodes.IOR;

	/**
	* Constant for the {@link #math math} method.
	*/
	public static final int XOR = Opcodes.IXOR;

	/**
	* Constant for the {@link #ifCmp ifCmp} method.
	*/
	public static final int EQ = Opcodes.IFEQ;

	/**
	* Constant for the {@link #ifCmp ifCmp} method.
	*/
	public static final int NE = Opcodes.IFNE;

	/**
	* Constant for the {@link #ifCmp ifCmp} method.
	*/
	public static final int LT = Opcodes.IFLT;

	/**
	* Constant for the {@link #ifCmp ifCmp} method.
	*/
	public static final int GE = Opcodes.IFGE;

	/**
	* Constant for the {@link #ifCmp ifCmp} method.
	*/
	public static final int GT = Opcodes.IFGT;

	/**
	* Constant for the {@link #ifCmp ifCmp} method.
	*/
	public static final 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<Type> localTypes = new ArrayList<Type>();

	/**
	* Creates a new {@link GeneratorAdapter}. <i>Subclasses must not use this
	* constructor</i>. Instead, they must use the
	* {@link #GeneratorAdapter(int, MethodVisitor, int, String, String)}
	* version.
	*
	* @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}).
	* @throws IllegalStateException
	* If a subclass calls this constructor.
	*/
	public GeneratorAdapter(final MethodVisitor mv, final int access,
	final String name, final String desc) {
	this(Opcodes.ASM6, mv, access, name, desc);
	if (getClass() != GeneratorAdapter.class) {
	throw new IllegalStateException();
	}
	}

	/**
	* Creates a new {@link GeneratorAdapter}.
	*
	* @param api
	* the ASM API version implemented by this visitor. Must be one
	* of {@link Opcodes#ASM4}, {@link Opcodes#ASM5} or {@link Opcodes#ASM6}.
	* @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}).
	*/
	protected GeneratorAdapter(final int api, final MethodVisitor mv,
	final int access, final String name, final String desc) {
	super(api, access, desc, mv);
	this.access = access;
	this.returnType = Type.getReturnType(desc);
	this.argumentTypes = Type.getArgumentTypes(desc);
	}

	/**
	* Creates a new {@link GeneratorAdapter}. <i>Subclasses must not use this
	* constructor</i>. Instead, they must use the
	* {@link #GeneratorAdapter(int, MethodVisitor, int, String, String)}
	* version.
	*
	* @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) {
	this(mv, access, null, method.getDescriptor());
	}

	/**
	* Creates a new {@link GeneratorAdapter}. <i>Subclasses must not use this
	* constructor</i>. Instead, they must use the
	* {@link #GeneratorAdapter(int, MethodVisitor, int, String, String)}
	* version.
	*
	* @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(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(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(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(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 {
	switch (value.getSort()) {
	case Type.BOOLEAN:
	mv.visitFieldInsn(Opcodes.GETSTATIC, "java/lang/Boolean",
	"TYPE", CLDESC);
	break;
	case Type.CHAR:
	mv.visitFieldInsn(Opcodes.GETSTATIC, "java/lang/Character",
	"TYPE", CLDESC);
	break;
	case Type.BYTE:
	mv.visitFieldInsn(Opcodes.GETSTATIC, "java/lang/Byte", "TYPE",
	CLDESC);
	break;
	case Type.SHORT:
	mv.visitFieldInsn(Opcodes.GETSTATIC, "java/lang/Short", "TYPE",
	CLDESC);
	break;
	case Type.INT:
	mv.visitFieldInsn(Opcodes.GETSTATIC, "java/lang/Integer",
	"TYPE", CLDESC);
	break;
	case Type.FLOAT:
	mv.visitFieldInsn(Opcodes.GETSTATIC, "java/lang/Float", "TYPE",
	CLDESC);
	break;
	case Type.LONG:
	mv.visitFieldInsn(Opcodes.GETSTATIC, "java/lang/Long", "TYPE",
	CLDESC);
	break;
	case Type.DOUBLE:
	mv.visitFieldInsn(Opcodes.GETSTATIC, "java/lang/Double",
	"TYPE", CLDESC);
	break;
	default:
	mv.visitLdcInsn(value);
	}
	}
	}

	/**
	* Generates the instruction to push a handle on the stack.
	*
	* @param handle
	* the handle to be pushed on the stack.
	*/
	public void push(final Handle handle) {
	mv.visitLdcInsn(handle);
	}

	// ------------------------------------------------------------------------
	// 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 localTypes.get(local - firstLocal);
	}

	@Override
	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
	// ------------------------------------------------------------------------

	private static Type getBoxedType(final Type type) {
	switch (type.getSort()) {
	case Type.BYTE:
	return BYTE_TYPE;
	case Type.BOOLEAN:
	return BOOLEAN_TYPE;
	case Type.SHORT:
	return SHORT_TYPE;
	case Type.CHAR:
	return CHARACTER_TYPE;
	case Type.INT:
	return INTEGER_TYPE;
	case Type.FLOAT:
	return FLOAT_TYPE;
	case Type.LONG:
	return LONG_TYPE;
	case Type.DOUBLE:
	return DOUBLE_TYPE;
	}
	return type;
	}

	/**
	* 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 = getBoxedType(type);
	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 box the top stack value using Java 5's
	* valueOf() method. This value is replaced by its boxed equivalent on top
	* of the stack.
	*
	* @param type
	* the type of the top stack value.
	*/
	public void valueOf(final Type type) {
	if (type.getSort() == Type.OBJECT \|\| type.getSort() == Type.ARRAY) {
	return;
	}
	if (type == Type.VOID_TYPE) {
	push((String) null);
	} else {
	Type boxed = getBoxedType(type);
	invokeStatic(boxed, new Method("valueOf", boxed,
	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) {
	switch (type.getSort()) {
	case Type.LONG:
	mv.visitInsn(Opcodes.LCMP);
	break;
	case Type.DOUBLE:
	mv.visitInsn(mode == GE \|\| mode == GT ? Opcodes.DCMPL
	: Opcodes.DCMPG);
	break;
	case Type.FLOAT:
	mv.visitInsn(mode == GE \|\| mode == GT ? Opcodes.FCMPL
	: 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:
	int intOp = -1;
	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;
	}
	mv.visitJumpInsn(mode, 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, final boolean itf) {
	String owner = type.getSort() == Type.ARRAY ? type.getDescriptor()
	: type.getInternalName();
	mv.visitMethodInsn(opcode, owner, method.getName(),
	method.getDescriptor(), itf);
	}

	/**
	* 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, false);
	}

	/**
	* 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, false);
	}

	/**
	* 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, false);
	}

	/**
	* 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, true);
	}

	/**
	* Generates an invokedynamic instruction.
	*
	* @param name
	* the method's name.
	* @param desc
	* the method's descriptor (see {@link Type Type}).
	* @param bsm
	* the bootstrap method.
	* @param bsmArgs
	* the bootstrap method constant arguments. Each argument must be
	* an {@link Integer}, {@link Float}, {@link Long},
	* {@link Double}, {@link String}, {@link Type} or {@link Handle}
	* value. This method is allowed to modify the content of the
	* array so a caller should expect that this array may change.
	*/
	public void invokeDynamic(String name, String desc, Handle bsm,
	Object... bsmArgs) {
	mv.visitInvokeDynamicInsn(name, desc, bsm, bsmArgs);
	}

	// ------------------------------------------------------------------------
	// 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) {
	mv.visitTypeInsn(opcode, type.getInternalName());
	}

	/**
	* 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) {
	Label doCatch = new Label();
	if (exception == null) {
	mv.visitTryCatchBlock(start, end, doCatch, null);
	} else {
	mv.visitTryCatchBlock(start, end, doCatch,
	exception.getInternalName());
	}
	mark(doCatch);
	}
	}

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