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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.HashSet;
	import java.util.List;
	import java.util.Set;
	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.FieldInsnNode;
	import jdk.internal.org.objectweb.asm.tree.InvokeDynamicInsnNode;
	import jdk.internal.org.objectweb.asm.tree.LdcInsnNode;
	import jdk.internal.org.objectweb.asm.tree.MethodInsnNode;

	/**
	* An {@link Interpreter} for {@link SourceValue} values.
	*
	* @author Eric Bruneton
	*/
	public class SourceInterpreter extends Interpreter<SourceValue> implements Opcodes {

	/**
	* Constructs a new {@link SourceInterpreter} for the latest ASM API version. <i>Subclasses must
	* not use this constructor</i>. Instead, they must use the {@link #SourceInterpreter(int)}
	* version.
	*/
	public SourceInterpreter() {
	super(/* latest api = */ ASM8);
	if (getClass() != SourceInterpreter.class) {
	throw new IllegalStateException();
	}
	}

	/**
	* Constructs a new {@link SourceInterpreter}.
	*
	* @param api the ASM API version supported by this interpreter. Must be one of {@link
	* jdk.internal.org.objectweb.asm.Opcodes#ASM4}, {@link jdk.internal.org.objectweb.asm.Opcodes#ASM5}, {@link
	* jdk.internal.org.objectweb.asm.Opcodes#ASM6}, {@link jdk.internal.org.objectweb.asm.Opcodes#ASM7} or {@link
	* jdk.internal.org.objectweb.asm.Opcodes#ASM8}.
	*/
	protected SourceInterpreter(final int api) {
	super(api);
	}

	@Override
	public SourceValue newValue(final Type type) {
	if (type == Type.VOID_TYPE) {
	return null;
	}
	return new SourceValue(type == null ? 1 : type.getSize());
	}

	@Override
	public SourceValue newOperation(final AbstractInsnNode insn) {
	int size;
	switch (insn.getOpcode()) {
	case LCONST_0:
	case LCONST_1:
	case DCONST_0:
	case DCONST_1:
	size = 2;
	break;
	case LDC:
	Object value = ((LdcInsnNode) insn).cst;
	size = value instanceof Long \|\| value instanceof Double ? 2 : 1;
	break;
	case GETSTATIC:
	size = Type.getType(((FieldInsnNode) insn).desc).getSize();
	break;
	default:
	size = 1;
	break;
	}
	return new SourceValue(size, insn);
	}

	@Override
	public SourceValue copyOperation(final AbstractInsnNode insn, final SourceValue value) {
	return new SourceValue(value.getSize(), insn);
	}

	@Override
	public SourceValue unaryOperation(final AbstractInsnNode insn, final SourceValue value) {
	int size;
	switch (insn.getOpcode()) {
	case LNEG:
	case DNEG:
	case I2L:
	case I2D:
	case L2D:
	case F2L:
	case F2D:
	case D2L:
	size = 2;
	break;
	case GETFIELD:
	size = Type.getType(((FieldInsnNode) insn).desc).getSize();
	break;
	default:
	size = 1;
	break;
	}
	return new SourceValue(size, insn);
	}

	@Override
	public SourceValue binaryOperation(
	final AbstractInsnNode insn, final SourceValue value1, final SourceValue value2) {
	int size;
	switch (insn.getOpcode()) {
	case LALOAD:
	case DALOAD:
	case LADD:
	case DADD:
	case LSUB:
	case DSUB:
	case LMUL:
	case DMUL:
	case LDIV:
	case DDIV:
	case LREM:
	case DREM:
	case LSHL:
	case LSHR:
	case LUSHR:
	case LAND:
	case LOR:
	case LXOR:
	size = 2;
	break;
	default:
	size = 1;
	break;
	}
	return new SourceValue(size, insn);
	}

	@Override
	public SourceValue ternaryOperation(
	final AbstractInsnNode insn,
	final SourceValue value1,
	final SourceValue value2,
	final SourceValue value3) {
	return new SourceValue(1, insn);
	}

	@Override
	public SourceValue naryOperation(
	final AbstractInsnNode insn, final List<? extends SourceValue> values) {
	int size;
	int opcode = insn.getOpcode();
	if (opcode == MULTIANEWARRAY) {
	size = 1;
	} else if (opcode == INVOKEDYNAMIC) {
	size = Type.getReturnType(((InvokeDynamicInsnNode) insn).desc).getSize();
	} else {
	size = Type.getReturnType(((MethodInsnNode) insn).desc).getSize();
	}
	return new SourceValue(size, insn);
	}

	@Override
	public void returnOperation(
	final AbstractInsnNode insn, final SourceValue value, final SourceValue expected) {
	// Nothing to do.
	}

	@Override
	public SourceValue merge(final SourceValue value1, final SourceValue value2) {
	if (value1.insns instanceof SmallSet && value2.insns instanceof SmallSet) {
	Set<AbstractInsnNode> setUnion =
	((SmallSet<AbstractInsnNode>) value1.insns)
	.union((SmallSet<AbstractInsnNode>) value2.insns);
	if (setUnion == value1.insns && value1.size == value2.size) {
	return value1;
	} else {
	return new SourceValue(Math.min(value1.size, value2.size), setUnion);
	}
	}
	if (value1.size != value2.size \|\| !containsAll(value1.insns, value2.insns)) {
	HashSet<AbstractInsnNode> setUnion = new HashSet<>();
	setUnion.addAll(value1.insns);
	setUnion.addAll(value2.insns);
	return new SourceValue(Math.min(value1.size, value2.size), setUnion);
	}
	return value1;
	}

	private static <E> boolean containsAll(final Set<E> self, final Set<E> other) {
	if (self.size() < other.size()) {
	return false;
	}
	return self.containsAll(other);
	}
	}

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