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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 jdk.internal.org.objectweb.asm.AnnotationVisitor;
	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;
	import jdk.internal.org.objectweb.asm.TypePath;

	/**
	* A {@link MethodVisitor} that renumbers local variables in their order of
	* appearance. This adapter allows one to easily add new local variables to a
	* method. It may be used by inheriting from this class, but the preferred way
	* of using it is via delegation: the next visitor in the chain can indeed add
	* new locals when needed by calling {@link #newLocal} on this adapter (this
	* requires a reference back to this {@link LocalVariablesSorter}).
	*
	* @author Chris Nokleberg
	* @author Eugene Kuleshov
	* @author Eric Bruneton
	*/
	public class LocalVariablesSorter extends MethodVisitor {

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

	/**
	* 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 int[] mapping = new int[40];

	/**
	* Array used to store stack map local variable types after remapping.
	*/
	private Object[] newLocals = new Object[20];

	/**
	* Index of the first local variable, after formal parameters.
	*/
	protected final int firstLocal;

	/**
	* Index of the next local variable to be created by {@link #newLocal}.
	*/
	protected int nextLocal;

	/**
	* Indicates if at least one local variable has moved due to remapping.
	*/
	private boolean changed;

	/**
	* Creates a new {@link LocalVariablesSorter}. <i>Subclasses must not use
	* this constructor</i>. Instead, they must use the
	* {@link #LocalVariablesSorter(int, int, String, MethodVisitor)} version.
	*
	* @param access
	* access flags of the adapted method.
	* @param desc
	* the method's descriptor (see {@link Type Type}).
	* @param mv
	* the method visitor to which this adapter delegates calls.
	* @throws IllegalStateException
	* If a subclass calls this constructor.
	*/
	public LocalVariablesSorter(final int access, final String desc,
	final MethodVisitor mv) {
	this(Opcodes.ASM5, access, desc, mv);
	if (getClass() != LocalVariablesSorter.class) {
	throw new IllegalStateException();
	}
	}

	/**
	* Creates a new {@link LocalVariablesSorter}.
	*
	* @param api
	* the ASM API version implemented by this visitor. Must be one
	* of {@link Opcodes#ASM4} or {@link Opcodes#ASM5}.
	* @param access
	* access flags of the adapted method.
	* @param desc
	* the method's descriptor (see {@link Type Type}).
	* @param mv
	* the method visitor to which this adapter delegates calls.
	*/
	protected LocalVariablesSorter(final int api, final int access,
	final String desc, final MethodVisitor mv) {
	super(api, mv);
	Type[] args = Type.getArgumentTypes(desc);
	nextLocal = (Opcodes.ACC_STATIC & access) == 0 ? 1 : 0;
	for (int i = 0; i < args.length; i++) {
	nextLocal += args[i].getSize();
	}
	firstLocal = nextLocal;
	}

	@Override
	public void visitVarInsn(final int opcode, final int var) {
	Type type;
	switch (opcode) {
	case Opcodes.LLOAD:
	case Opcodes.LSTORE:
	type = Type.LONG_TYPE;
	break;

	case Opcodes.DLOAD:
	case Opcodes.DSTORE:
	type = Type.DOUBLE_TYPE;
	break;

	case Opcodes.FLOAD:
	case Opcodes.FSTORE:
	type = Type.FLOAT_TYPE;
	break;

	case Opcodes.ILOAD:
	case Opcodes.ISTORE:
	type = Type.INT_TYPE;
	break;

	default:
	// case Opcodes.ALOAD:
	// case Opcodes.ASTORE:
	// case RET:
	type = OBJECT_TYPE;
	break;
	}
	mv.visitVarInsn(opcode, remap(var, type));
	}

	@Override
	public void visitIincInsn(final int var, final int increment) {
	mv.visitIincInsn(remap(var, Type.INT_TYPE), increment);
	}

	@Override
	public void visitMaxs(final int maxStack, final int maxLocals) {
	mv.visitMaxs(maxStack, nextLocal);
	}

	@Override
	public void visitLocalVariable(final String name, final String desc,
	final String signature, final Label start, final Label end,
	final int index) {
	int newIndex = remap(index, Type.getType(desc));
	mv.visitLocalVariable(name, desc, signature, start, end, newIndex);
	}

	@Override
	public AnnotationVisitor visitLocalVariableAnnotation(int typeRef,
	TypePath typePath, Label[] start, Label[] end, int[] index,
	String desc, boolean visible) {
	Type t = Type.getType(desc);
	int[] newIndex = new int[index.length];
	for (int i = 0; i < newIndex.length; ++i) {
	newIndex[i] = remap(index[i], t);
	}
	return mv.visitLocalVariableAnnotation(typeRef, typePath, start, end,
	newIndex, desc, visible);
	}

	@Override
	public void visitFrame(final int type, final int nLocal,
	final Object[] local, final int nStack, final Object[] stack) {
	if (type != Opcodes.F_NEW) { // uncompressed frame
	throw new IllegalStateException(
	"ClassReader.accept() should be called with EXPAND_FRAMES flag");
	}

	if (!changed) { // optimization for the case where mapping = identity
	mv.visitFrame(type, nLocal, local, nStack, stack);
	return;
	}

	// creates a copy of newLocals
	Object[] oldLocals = new Object[newLocals.length];
	System.arraycopy(newLocals, 0, oldLocals, 0, oldLocals.length);

	updateNewLocals(newLocals);

	// copies types from 'local' to 'newLocals'
	// 'newLocals' already contains the variables added with 'newLocal'

	int index = 0; // old local variable index
	int number = 0; // old local variable number
	for (; number < nLocal; ++number) {
	Object t = local[number];
	int size = t == Opcodes.LONG \|\| t == Opcodes.DOUBLE ? 2 : 1;
	if (t != Opcodes.TOP) {
	Type typ = OBJECT_TYPE;
	if (t == Opcodes.INTEGER) {
	typ = Type.INT_TYPE;
	} else if (t == Opcodes.FLOAT) {
	typ = Type.FLOAT_TYPE;
	} else if (t == Opcodes.LONG) {
	typ = Type.LONG_TYPE;
	} else if (t == Opcodes.DOUBLE) {
	typ = Type.DOUBLE_TYPE;
	} else if (t instanceof String) {
	typ = Type.getObjectType((String) t);
	}
	setFrameLocal(remap(index, typ), t);
	}
	index += size;
	}

	// removes TOP after long and double types as well as trailing TOPs

	index = 0;
	number = 0;
	for (int i = 0; index < newLocals.length; ++i) {
	Object t = newLocals[index++];
	if (t != null && t != Opcodes.TOP) {
	newLocals[i] = t;
	number = i + 1;
	if (t == Opcodes.LONG \|\| t == Opcodes.DOUBLE) {
	index += 1;
	}
	} else {
	newLocals[i] = Opcodes.TOP;
	}
	}

	// visits remapped frame
	mv.visitFrame(type, number, newLocals, nStack, stack);

	// restores original value of 'newLocals'
	newLocals = oldLocals;
	}

	// -------------

	/**
	* Creates a new local variable of the given type.
	*
	* @param type
	* the type of the local variable to be created.
	* @return the identifier of the newly created local variable.
	*/
	public int newLocal(final Type type) {
	Object t;
	switch (type.getSort()) {
	case Type.BOOLEAN:
	case Type.CHAR:
	case Type.BYTE:
	case Type.SHORT:
	case Type.INT:
	t = Opcodes.INTEGER;
	break;
	case Type.FLOAT:
	t = Opcodes.FLOAT;
	break;
	case Type.LONG:
	t = Opcodes.LONG;
	break;
	case Type.DOUBLE:
	t = Opcodes.DOUBLE;
	break;
	case Type.ARRAY:
	t = type.getDescriptor();
	break;
	// case Type.OBJECT:
	default:
	t = type.getInternalName();
	break;
	}
	int local = newLocalMapping(type);
	setLocalType(local, type);
	setFrameLocal(local, t);
	changed = true;
	return local;
	}

	/**
	* Notifies subclasses that a new stack map frame is being visited. The
	* array argument contains the stack map frame types corresponding to the
	* local variables added with {@link #newLocal}. This method can update
	* these types in place for the stack map frame being visited. The default
	* implementation of this method does nothing, i.e. a local variable added
	* with {@link #newLocal} will have the same type in all stack map frames.
	* But this behavior is not always the desired one, for instance if a local
	* variable is added in the middle of a try/catch block: the frame for the
	* exception handler should have a TOP type for this new local.
	*
	* @param newLocals
	* the stack map frame types corresponding to the local variables
	* added with {@link #newLocal} (and null for the others). The
	* format of this array is the same as in
	* {@link MethodVisitor#visitFrame}, except that long and double
	* types use two slots. The types for the current stack map frame
	* must be updated in place in this array.
	*/
	protected void updateNewLocals(Object[] newLocals) {
	}

	/**
	* Notifies subclasses that a local variable has been added or remapped. The
	* default implementation of this method does nothing.
	*
	* @param local
	* a local variable identifier, as returned by {@link #newLocal
	* newLocal()}.
	* @param type
	* the type of the value being stored in the local variable.
	*/
	protected void setLocalType(final int local, final Type type) {
	}

	private void setFrameLocal(final int local, final Object type) {
	int l = newLocals.length;
	if (local >= l) {
	Object[] a = new Object[Math.max(2 * l, local + 1)];
	System.arraycopy(newLocals, 0, a, 0, l);
	newLocals = a;
	}
	newLocals[local] = type;
	}

	private int remap(final int var, final Type type) {
	if (var + type.getSize() <= firstLocal) {
	return var;
	}
	int key = 2 * var + type.getSize() - 1;
	int size = mapping.length;
	if (key >= size) {
	int[] newMapping = new int[Math.max(2 * size, key + 1)];
	System.arraycopy(mapping, 0, newMapping, 0, size);
	mapping = newMapping;
	}
	int value = mapping[key];
	if (value == 0) {
	value = newLocalMapping(type);
	setLocalType(value, type);
	mapping[key] = value + 1;
	} else {
	value--;
	}
	if (value != var) {
	changed = true;
	}
	return value;
	}

	protected int newLocalMapping(final Type type) {
	int local = nextLocal;
	nextLocal += type.getSize();
	return local;
	}
	}

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