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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.tree.analysis;

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

	import jdk.internal.org.objectweb.asm.Opcodes;
	import jdk.internal.org.objectweb.asm.Type;
	import jdk.internal.org.objectweb.asm.tree.AbstractInsnNode;
	import jdk.internal.org.objectweb.asm.tree.IincInsnNode;
	import jdk.internal.org.objectweb.asm.tree.InvokeDynamicInsnNode;
	import jdk.internal.org.objectweb.asm.tree.MethodInsnNode;
	import jdk.internal.org.objectweb.asm.tree.MultiANewArrayInsnNode;
	import jdk.internal.org.objectweb.asm.tree.VarInsnNode;

	/**
	* A symbolic execution stack frame. A stack frame contains a set of local
	* variable slots, and an operand stack. Warning: long and double values are
	* represented by <i>two</i> slots in local variables, and by <i>one</i> slot in
	* the operand stack.
	*
	* @param <V>
	* type of the Value used for the analysis.
	*
	* @author Eric Bruneton
	*/
	public class Frame<V extends Value> {

	/**
	* The expected return type of the analyzed method, or <tt>null</tt> if the
	* method returns void.
	*/
	private V returnValue;

	/**
	* The local variables and operand stack of this frame.
	*/
	private V[] values;

	/**
	* The number of local variables of this frame.
	*/
	private int locals;

	/**
	* The number of elements in the operand stack.
	*/
	private int top;

	/**
	* Constructs a new frame with the given size.
	*
	* @param nLocals
	* the maximum number of local variables of the frame.
	* @param nStack
	* the maximum stack size of the frame.
	*/
	@SuppressWarnings("unchecked")
	public Frame(final int nLocals, final int nStack) {
	this.values = (V[]) new Value[nLocals + nStack];
	this.locals = nLocals;
	}

	/**
	* Constructs a new frame that is identical to the given frame.
	*
	* @param src
	* a frame.
	*/
	public Frame(final Frame<? extends V> src) {
	this(src.locals, src.values.length - src.locals);
	init(src);
	}

	/**
	* Copies the state of the given frame into this frame.
	*
	* @param src
	* a frame.
	* @return this frame.
	*/
	public Frame<V> init(final Frame<? extends V> src) {
	returnValue = src.returnValue;
	System.arraycopy(src.values, 0, values, 0, values.length);
	top = src.top;
	return this;
	}

	/**
	* Sets the expected return type of the analyzed method.
	*
	* @param v
	* the expected return type of the analyzed method, or
	* <tt>null</tt> if the method returns void.
	*/
	public void setReturn(final V v) {
	returnValue = v;
	}

	/**
	* Returns the maximum number of local variables of this frame.
	*
	* @return the maximum number of local variables of this frame.
	*/
	public int getLocals() {
	return locals;
	}

	/**
	* Returns the maximum stack size of this frame.
	*
	* @return the maximum stack size of this frame.
	*/
	public int getMaxStackSize() {
	return values.length - locals;
	}

	/**
	* Returns the value of the given local variable.
	*
	* @param i
	* a local variable index.
	* @return the value of the given local variable.
	* @throws IndexOutOfBoundsException
	* if the variable does not exist.
	*/
	public V getLocal(final int i) throws IndexOutOfBoundsException {
	if (i >= locals) {
	throw new IndexOutOfBoundsException(
	"Trying to access an inexistant local variable");
	}
	return values[i];
	}

	/**
	* Sets the value of the given local variable.
	*
	* @param i
	* a local variable index.
	* @param value
	* the new value of this local variable.
	* @throws IndexOutOfBoundsException
	* if the variable does not exist.
	*/
	public void setLocal(final int i, final V value)
	throws IndexOutOfBoundsException {
	if (i >= locals) {
	throw new IndexOutOfBoundsException(
	"Trying to access an inexistant local variable " + i);
	}
	values[i] = value;
	}

	/**
	* Returns the number of values in the operand stack of this frame. Long and
	* double values are treated as single values.
	*
	* @return the number of values in the operand stack of this frame.
	*/
	public int getStackSize() {
	return top;
	}

	/**
	* Returns the value of the given operand stack slot.
	*
	* @param i
	* the index of an operand stack slot.
	* @return the value of the given operand stack slot.
	* @throws IndexOutOfBoundsException
	* if the operand stack slot does not exist.
	*/
	public V getStack(final int i) throws IndexOutOfBoundsException {
	return values[i + locals];
	}

	/**
	* Clears the operand stack of this frame.
	*/
	public void clearStack() {
	top = 0;
	}

	/**
	* Pops a value from the operand stack of this frame.
	*
	* @return the value that has been popped from the stack.
	* @throws IndexOutOfBoundsException
	* if the operand stack is empty.
	*/
	public V pop() throws IndexOutOfBoundsException {
	if (top == 0) {
	throw new IndexOutOfBoundsException(
	"Cannot pop operand off an empty stack.");
	}
	return values[--top + locals];
	}

	/**
	* Pushes a value into the operand stack of this frame.
	*
	* @param value
	* the value that must be pushed into the stack.
	* @throws IndexOutOfBoundsException
	* if the operand stack is full.
	*/
	public void push(final V value) throws IndexOutOfBoundsException {
	if (top + locals >= values.length) {
	throw new IndexOutOfBoundsException(
	"Insufficient maximum stack size.");
	}
	values[top++ + locals] = value;
	}

	public void execute(final AbstractInsnNode insn,
	final Interpreter<V> interpreter) throws AnalyzerException {
	V value1, value2, value3, value4;
	List<V> values;
	int var;

	switch (insn.getOpcode()) {
	case Opcodes.NOP:
	break;
	case Opcodes.ACONST_NULL:
	case Opcodes.ICONST_M1:
	case Opcodes.ICONST_0:
	case Opcodes.ICONST_1:
	case Opcodes.ICONST_2:
	case Opcodes.ICONST_3:
	case Opcodes.ICONST_4:
	case Opcodes.ICONST_5:
	case Opcodes.LCONST_0:
	case Opcodes.LCONST_1:
	case Opcodes.FCONST_0:
	case Opcodes.FCONST_1:
	case Opcodes.FCONST_2:
	case Opcodes.DCONST_0:
	case Opcodes.DCONST_1:
	case Opcodes.BIPUSH:
	case Opcodes.SIPUSH:
	case Opcodes.LDC:
	push(interpreter.newOperation(insn));
	break;
	case Opcodes.ILOAD:
	case Opcodes.LLOAD:
	case Opcodes.FLOAD:
	case Opcodes.DLOAD:
	case Opcodes.ALOAD:
	push(interpreter.copyOperation(insn,
	getLocal(((VarInsnNode) insn).var)));
	break;
	case Opcodes.IALOAD:
	case Opcodes.LALOAD:
	case Opcodes.FALOAD:
	case Opcodes.DALOAD:
	case Opcodes.AALOAD:
	case Opcodes.BALOAD:
	case Opcodes.CALOAD:
	case Opcodes.SALOAD:
	value2 = pop();
	value1 = pop();
	push(interpreter.binaryOperation(insn, value1, value2));
	break;
	case Opcodes.ISTORE:
	case Opcodes.LSTORE:
	case Opcodes.FSTORE:
	case Opcodes.DSTORE:
	case Opcodes.ASTORE:
	value1 = interpreter.copyOperation(insn, pop());
	var = ((VarInsnNode) insn).var;
	setLocal(var, value1);
	if (value1.getSize() == 2) {
	setLocal(var + 1, interpreter.newValue(null));
	}
	if (var > 0) {
	Value local = getLocal(var - 1);
	if (local != null && local.getSize() == 2) {
	setLocal(var - 1, interpreter.newValue(null));
	}
	}
	break;
	case Opcodes.IASTORE:
	case Opcodes.LASTORE:
	case Opcodes.FASTORE:
	case Opcodes.DASTORE:
	case Opcodes.AASTORE:
	case Opcodes.BASTORE:
	case Opcodes.CASTORE:
	case Opcodes.SASTORE:
	value3 = pop();
	value2 = pop();
	value1 = pop();
	interpreter.ternaryOperation(insn, value1, value2, value3);
	break;
	case Opcodes.POP:
	if (pop().getSize() == 2) {
	throw new AnalyzerException(insn, "Illegal use of POP");
	}
	break;
	case Opcodes.POP2:
	if (pop().getSize() == 1) {
	if (pop().getSize() != 1) {
	throw new AnalyzerException(insn, "Illegal use of POP2");
	}
	}
	break;
	case Opcodes.DUP:
	value1 = pop();
	if (value1.getSize() != 1) {
	throw new AnalyzerException(insn, "Illegal use of DUP");
	}
	push(value1);
	push(interpreter.copyOperation(insn, value1));
	break;
	case Opcodes.DUP_X1:
	value1 = pop();
	value2 = pop();
	if (value1.getSize() != 1 \|\| value2.getSize() != 1) {
	throw new AnalyzerException(insn, "Illegal use of DUP_X1");
	}
	push(interpreter.copyOperation(insn, value1));
	push(value2);
	push(value1);
	break;
	case Opcodes.DUP_X2:
	value1 = pop();
	if (value1.getSize() == 1) {
	value2 = pop();
	if (value2.getSize() == 1) {
	value3 = pop();
	if (value3.getSize() == 1) {
	push(interpreter.copyOperation(insn, value1));
	push(value3);
	push(value2);
	push(value1);
	break;
	}
	} else {
	push(interpreter.copyOperation(insn, value1));
	push(value2);
	push(value1);
	break;
	}
	}
	throw new AnalyzerException(insn, "Illegal use of DUP_X2");
	case Opcodes.DUP2:
	value1 = pop();
	if (value1.getSize() == 1) {
	value2 = pop();
	if (value2.getSize() == 1) {
	push(value2);
	push(value1);
	push(interpreter.copyOperation(insn, value2));
	push(interpreter.copyOperation(insn, value1));
	break;
	}
	} else {
	push(value1);
	push(interpreter.copyOperation(insn, value1));
	break;
	}
	throw new AnalyzerException(insn, "Illegal use of DUP2");
	case Opcodes.DUP2_X1:
	value1 = pop();
	if (value1.getSize() == 1) {
	value2 = pop();
	if (value2.getSize() == 1) {
	value3 = pop();
	if (value3.getSize() == 1) {
	push(interpreter.copyOperation(insn, value2));
	push(interpreter.copyOperation(insn, value1));
	push(value3);
	push(value2);
	push(value1);
	break;
	}
	}
	} else {
	value2 = pop();
	if (value2.getSize() == 1) {
	push(interpreter.copyOperation(insn, value1));
	push(value2);
	push(value1);
	break;
	}
	}
	throw new AnalyzerException(insn, "Illegal use of DUP2_X1");
	case Opcodes.DUP2_X2:
	value1 = pop();
	if (value1.getSize() == 1) {
	value2 = pop();
	if (value2.getSize() == 1) {
	value3 = pop();
	if (value3.getSize() == 1) {
	value4 = pop();
	if (value4.getSize() == 1) {
	push(interpreter.copyOperation(insn, value2));
	push(interpreter.copyOperation(insn, value1));
	push(value4);
	push(value3);
	push(value2);
	push(value1);
	break;
	}
	} else {
	push(interpreter.copyOperation(insn, value2));
	push(interpreter.copyOperation(insn, value1));
	push(value3);
	push(value2);
	push(value1);
	break;
	}
	}
	} else {
	value2 = pop();
	if (value2.getSize() == 1) {
	value3 = pop();
	if (value3.getSize() == 1) {
	push(interpreter.copyOperation(insn, value1));
	push(value3);
	push(value2);
	push(value1);
	break;
	}
	} else {
	push(interpreter.copyOperation(insn, value1));
	push(value2);
	push(value1);
	break;
	}
	}
	throw new AnalyzerException(insn, "Illegal use of DUP2_X2");
	case Opcodes.SWAP:
	value2 = pop();
	value1 = pop();
	if (value1.getSize() != 1 \|\| value2.getSize() != 1) {
	throw new AnalyzerException(insn, "Illegal use of SWAP");
	}
	push(interpreter.copyOperation(insn, value2));
	push(interpreter.copyOperation(insn, value1));
	break;
	case Opcodes.IADD:
	case Opcodes.LADD:
	case Opcodes.FADD:
	case Opcodes.DADD:
	case Opcodes.ISUB:
	case Opcodes.LSUB:
	case Opcodes.FSUB:
	case Opcodes.DSUB:
	case Opcodes.IMUL:
	case Opcodes.LMUL:
	case Opcodes.FMUL:
	case Opcodes.DMUL:
	case Opcodes.IDIV:
	case Opcodes.LDIV:
	case Opcodes.FDIV:
	case Opcodes.DDIV:
	case Opcodes.IREM:
	case Opcodes.LREM:
	case Opcodes.FREM:
	case Opcodes.DREM:
	value2 = pop();
	value1 = pop();
	push(interpreter.binaryOperation(insn, value1, value2));
	break;
	case Opcodes.INEG:
	case Opcodes.LNEG:
	case Opcodes.FNEG:
	case Opcodes.DNEG:
	push(interpreter.unaryOperation(insn, pop()));
	break;
	case Opcodes.ISHL:
	case Opcodes.LSHL:
	case Opcodes.ISHR:
	case Opcodes.LSHR:
	case Opcodes.IUSHR:
	case Opcodes.LUSHR:
	case Opcodes.IAND:
	case Opcodes.LAND:
	case Opcodes.IOR:
	case Opcodes.LOR:
	case Opcodes.IXOR:
	case Opcodes.LXOR:
	value2 = pop();
	value1 = pop();
	push(interpreter.binaryOperation(insn, value1, value2));
	break;
	case Opcodes.IINC:
	var = ((IincInsnNode) insn).var;
	setLocal(var, interpreter.unaryOperation(insn, getLocal(var)));
	break;
	case Opcodes.I2L:
	case Opcodes.I2F:
	case Opcodes.I2D:
	case Opcodes.L2I:
	case Opcodes.L2F:
	case Opcodes.L2D:
	case Opcodes.F2I:
	case Opcodes.F2L:
	case Opcodes.F2D:
	case Opcodes.D2I:
	case Opcodes.D2L:
	case Opcodes.D2F:
	case Opcodes.I2B:
	case Opcodes.I2C:
	case Opcodes.I2S:
	push(interpreter.unaryOperation(insn, pop()));
	break;
	case Opcodes.LCMP:
	case Opcodes.FCMPL:
	case Opcodes.FCMPG:
	case Opcodes.DCMPL:
	case Opcodes.DCMPG:
	value2 = pop();
	value1 = pop();
	push(interpreter.binaryOperation(insn, value1, value2));
	break;
	case Opcodes.IFEQ:
	case Opcodes.IFNE:
	case Opcodes.IFLT:
	case Opcodes.IFGE:
	case Opcodes.IFGT:
	case Opcodes.IFLE:
	interpreter.unaryOperation(insn, pop());
	break;
	case Opcodes.IF_ICMPEQ:
	case Opcodes.IF_ICMPNE:
	case Opcodes.IF_ICMPLT:
	case Opcodes.IF_ICMPGE:
	case Opcodes.IF_ICMPGT:
	case Opcodes.IF_ICMPLE:
	case Opcodes.IF_ACMPEQ:
	case Opcodes.IF_ACMPNE:
	value2 = pop();
	value1 = pop();
	interpreter.binaryOperation(insn, value1, value2);
	break;
	case Opcodes.GOTO:
	break;
	case Opcodes.JSR:
	push(interpreter.newOperation(insn));
	break;
	case Opcodes.RET:
	break;
	case Opcodes.TABLESWITCH:
	case Opcodes.LOOKUPSWITCH:
	interpreter.unaryOperation(insn, pop());
	break;
	case Opcodes.IRETURN:
	case Opcodes.LRETURN:
	case Opcodes.FRETURN:
	case Opcodes.DRETURN:
	case Opcodes.ARETURN:
	value1 = pop();
	interpreter.unaryOperation(insn, value1);
	interpreter.returnOperation(insn, value1, returnValue);
	break;
	case Opcodes.RETURN:
	if (returnValue != null) {
	throw new AnalyzerException(insn, "Incompatible return type");
	}
	break;
	case Opcodes.GETSTATIC:
	push(interpreter.newOperation(insn));
	break;
	case Opcodes.PUTSTATIC:
	interpreter.unaryOperation(insn, pop());
	break;
	case Opcodes.GETFIELD:
	push(interpreter.unaryOperation(insn, pop()));
	break;
	case Opcodes.PUTFIELD:
	value2 = pop();
	value1 = pop();
	interpreter.binaryOperation(insn, value1, value2);
	break;
	case Opcodes.INVOKEVIRTUAL:
	case Opcodes.INVOKESPECIAL:
	case Opcodes.INVOKESTATIC:
	case Opcodes.INVOKEINTERFACE: {
	values = new ArrayList<V>();
	String desc = ((MethodInsnNode) insn).desc;
	for (int i = Type.getArgumentTypes(desc).length; i > 0; --i) {
	values.add(0, pop());
	}
	if (insn.getOpcode() != Opcodes.INVOKESTATIC) {
	values.add(0, pop());
	}
	if (Type.getReturnType(desc) == Type.VOID_TYPE) {
	interpreter.naryOperation(insn, values);
	} else {
	push(interpreter.naryOperation(insn, values));
	}
	break;
	}
	case Opcodes.INVOKEDYNAMIC: {
	values = new ArrayList<V>();
	String desc = ((InvokeDynamicInsnNode) insn).desc;
	for (int i = Type.getArgumentTypes(desc).length; i > 0; --i) {
	values.add(0, pop());
	}
	if (Type.getReturnType(desc) == Type.VOID_TYPE) {
	interpreter.naryOperation(insn, values);
	} else {
	push(interpreter.naryOperation(insn, values));
	}
	break;
	}
	case Opcodes.NEW:
	push(interpreter.newOperation(insn));
	break;
	case Opcodes.NEWARRAY:
	case Opcodes.ANEWARRAY:
	case Opcodes.ARRAYLENGTH:
	push(interpreter.unaryOperation(insn, pop()));
	break;
	case Opcodes.ATHROW:
	interpreter.unaryOperation(insn, pop());
	break;
	case Opcodes.CHECKCAST:
	case Opcodes.INSTANCEOF:
	push(interpreter.unaryOperation(insn, pop()));
	break;
	case Opcodes.MONITORENTER:
	case Opcodes.MONITOREXIT:
	interpreter.unaryOperation(insn, pop());
	break;
	case Opcodes.MULTIANEWARRAY:
	values = new ArrayList<V>();
	for (int i = ((MultiANewArrayInsnNode) insn).dims; i > 0; --i) {
	values.add(0, pop());
	}
	push(interpreter.naryOperation(insn, values));
	break;
	case Opcodes.IFNULL:
	case Opcodes.IFNONNULL:
	interpreter.unaryOperation(insn, pop());
	break;
	default:
	throw new RuntimeException("Illegal opcode " + insn.getOpcode());
	}
	}

	/**
	* Merges this frame with the given frame.
	*
	* @param frame
	* a frame.
	* @param interpreter
	* the interpreter used to merge values.
	* @return <tt>true</tt> if this frame has been changed as a result of the
	* merge operation, or <tt>false</tt> otherwise.
	* @throws AnalyzerException
	* if the frames have incompatible sizes.
	*/
	public boolean merge(final Frame<? extends V> frame,
	final Interpreter<V> interpreter) throws AnalyzerException {
	if (top != frame.top) {
	throw new AnalyzerException(null, "Incompatible stack heights");
	}
	boolean changes = false;
	for (int i = 0; i < locals + top; ++i) {
	V v = interpreter.merge(values[i], frame.values[i]);
	if (!v.equals(values[i])) {
	values[i] = v;
	changes = true;
	}
	}
	return changes;
	}

	/**
	* Merges this frame with the given frame (case of a RET instruction).
	*
	* @param frame
	* a frame
	* @param access
	* the local variables that have been accessed by the subroutine
	* to which the RET instruction corresponds.
	* @return <tt>true</tt> if this frame has been changed as a result of the
	* merge operation, or <tt>false</tt> otherwise.
	*/
	public boolean merge(final Frame<? extends V> frame, final boolean[] access) {
	boolean changes = false;
	for (int i = 0; i < locals; ++i) {
	if (!access[i] && !values[i].equals(frame.values[i])) {
	values[i] = frame.values[i];
	changes = true;
	}
	}
	return changes;
	}

	/**
	* Returns a string representation of this frame.
	*
	* @return a string representation of this frame.
	*/
	@Override
	public String toString() {
	StringBuilder sb = new StringBuilder();
	for (int i = 0; i < getLocals(); ++i) {
	sb.append(getLocal(i));
	}
	sb.append(' ');
	for (int i = 0; i < getStackSize(); ++i) {
	sb.append(getStack(i).toString());
	}
	return sb.toString();
	}
	}

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