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 * reserved comment block

 * DO NOT REMOVE OR ALTER!

 */

/*

 * Licensed to the Apache Software Foundation (ASF) under one or more

 * contributor license agreements.  See the NOTICE file distributed with

 * this work for additional information regarding copyright ownership.

 * The ASF licenses this file to You under the Apache License, Version 2.0

 * (the "License"); you may not use this file except in compliance with

 * the License.  You may obtain a copy of the License at

 *

 *      http://www.apache.org/licenses/LICENSE-2.0

 *

 * Unless required by applicable law or agreed to in writing, software

 * distributed under the License is distributed on an "AS IS" BASIS,

 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

 * See the License for the specific language governing permissions and

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package com.sun.org.apache.bcel.internal.generic;

/**

 * Equality of instructions isn't clearly to be defined. You might

 * wish, for example, to compare whether instructions have the same

 * meaning. E.g., whether two INVOKEVIRTUALs describe the same

 * call.

 * <p>

 * The DEFAULT comparator however, considers two instructions

 * to be equal if they have same opcode and point to the same indexes

 * (if any) in the constant pool or the same local variable index. Branch

 * instructions must have the same target.

 * </p>

 *

 * @see Instruction

 */

public interface InstructionComparator {

    InstructionComparator DEFAULT = (i1, i2) -> {

        if (i1.getOpcode() == i2.getOpcode()) {

            if (i1 instanceof BranchInstruction) {

             // BIs are never equal to make targeters work correctly (BCEL-195)

                return false;

//                } else if (i1 == i2) { TODO consider adding this shortcut

//                    return true; // this must be AFTER the BI test

            } else if (i1 instanceof ConstantPushInstruction) {

                return ((ConstantPushInstruction) i1).getValue().equals(

                        ((ConstantPushInstruction) i2).getValue());

            } else if (i1 instanceof IndexedInstruction) {

                return ((IndexedInstruction) i1).getIndex() == ((IndexedInstruction) i2)

                        .getIndex();

            } else if (i1 instanceof NEWARRAY) {

                return ((NEWARRAY) i1).getTypecode() == ((NEWARRAY) i2).getTypecode();

            } else {

                return true;

            }

        }

        return false;

    };

    boolean equals( Instruction i1, Instruction i2 );

}