48 lines
1.5 KiB
Java
48 lines
1.5 KiB
Java
/*******************************************************************************
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* Copyright (c) 2002 - 2006 IBM Corporation.
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* All rights reserved. This program and the accompanying materials
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* are made available under the terms of the Eclipse Public License v1.0
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* which accompanies this distribution, and is available at
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* http://www.eclipse.org/legal/epl-v10.html
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*
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* Contributors:
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* IBM Corporation - initial API and implementation
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*******************************************************************************/
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package com.ibm.wala.fixpoint;
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import com.ibm.wala.util.debug.Assertions;
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import com.ibm.wala.util.debug.UnimplementedError;
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/**
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* An operator of the form lhs = op (rhs)
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*/
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@SuppressWarnings("rawtypes")
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public abstract class UnaryOperator<T extends IVariable> extends AbstractOperator<T> implements FixedPointConstants {
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/**
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* Evaluate this equation, setting a new value for the left-hand side.
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*
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* @return true if the lhs value changes. false otherwise.
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*/
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public abstract byte evaluate(T lhs, T rhs);
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/**
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* Create an equation which uses this operator Override in subclasses for
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* efficiency.
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*/
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public UnaryStatement<T> makeEquation(T lhs, T rhs) {
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return new BasicUnaryStatement<T>(lhs, this, rhs);
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}
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public boolean isIdentity() {
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return false;
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}
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@Override
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public byte evaluate(T lhs, T[] rhs) throws UnimplementedError {
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// this should never be called. Use the other, more efficient form.
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Assertions.UNREACHABLE();
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return 0;
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}
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}
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