001    /*
002     *  This file is part of the Jikes RVM project (http://jikesrvm.org).
003     *
004     *  This file is licensed to You under the Common Public License (CPL);
005     *  You may not use this file except in compliance with the License. You
006     *  may obtain a copy of the License at
007     *
008     *      http://www.opensource.org/licenses/cpl1.0.php
009     *
010     *  See the COPYRIGHT.txt file distributed with this work for information
011     *  regarding copyright ownership.
012     */
013    package org.jikesrvm.compilers.opt.ir.operand;
014    
015    import org.jikesrvm.compilers.opt.ir.BasicBlock;
016    
017    /**
018     * Represents a basic block (used in LABEL and BBEND instructions)
019     *
020     * @see Operand
021     */
022    public final class BasicBlockOperand extends Operand {
023    
024      /**
025       * The basic block
026       */
027      public BasicBlock block;
028    
029      /**
030       * Construct a new basic block operand with the given block.
031       *
032       * @param b the basic block
033       */
034      public BasicBlockOperand(BasicBlock b) {
035        block = b;
036      }
037    
038      /**
039       * Return a new operand that is semantically equivalent to <code>this</code>.
040       *
041       * @return a copy of <code>this</code>
042       */
043      public Operand copy() {
044        return new BasicBlockOperand(block);
045      }
046    
047      /**
048       * Are two operands semantically equivalent?
049       *
050       * @param op other operand
051       * @return   <code>true</code> if <code>this</code> and <code>op</code>
052       *           are semantically equivalent or <code>false</code>
053       *           if they are not.
054       */
055      public boolean similar(Operand op) {
056        return (op instanceof BasicBlockOperand) && (block == ((BasicBlockOperand) op).block);
057      }
058    
059      /**
060       * Returns the string representation of this operand.
061       *
062       * @return a string representation of this operand.
063       */
064      public String toString() {
065        return block.toString();
066      }
067    }