WALA/com.ibm.wala.cast.js/source/com/ibm/wala/cast/js/ipa/callgraph/correlations/EscapeCorrelation.java

64 lines
2.3 KiB
Java

/*******************************************************************************
* Copyright (c) 2011 IBM Corporation.
* All rights reserved. This program and the accompanying materials
* are made available under the terms of the Eclipse Public License v1.0
* which accompanies this distribution, and is available at
* http://www.eclipse.org/legal/epl-v10.html
*
* Contributors:
* IBM Corporation - initial API and implementation
*******************************************************************************/
package com.ibm.wala.cast.js.ipa.callgraph.correlations;
import java.util.Set;
import com.ibm.wala.cast.ir.ssa.AbstractReflectiveGet;
import com.ibm.wala.cast.tree.CAstSourcePositionMap.Position;
import com.ibm.wala.ssa.SSAAbstractInvokeInstruction;
/**
* An escape correlation conservatively captures inter-procedural correlated pairs: for a dynamic property
* read <i>r</i> of the form <code>e[p]</code>, if both the result of <i>r</i> and the value of <code>p</code>
* flow into a function call <i>c</i>, we consider <i>r</i> and <i>c</i> to be a correlated pair to account
* for the fact that the function called by <i>c</i> may perform a write of property <code>p</code>.
*
* @author mschaefer
*
*/
public class EscapeCorrelation extends Correlation {
private final AbstractReflectiveGet get;
private final SSAAbstractInvokeInstruction invoke;
public EscapeCorrelation(AbstractReflectiveGet get, SSAAbstractInvokeInstruction invoke,
String indexName, Set<String> flownThroughLocals) {
super(indexName, flownThroughLocals);
this.get = get;
this.invoke = invoke;
}
@Override
public Position getStartPosition(SSASourcePositionMap positions) {
return positions.getPosition(get);
}
@Override
public Position getEndPosition(SSASourcePositionMap positions) {
return positions.getPosition(invoke);
}
public int getNumberOfArguments() {
return invoke.getNumberOfPositionalParameters() - 2; // deduct one for the function object, one for the receiver
}
@Override
public String pp(SSASourcePositionMap positions) {
return get + "@" + positions.getPosition(get) + " [" + getIndexName() + "] ->? " + invoke + "@" + positions.getPosition(invoke);
}
@Override
public <T> T accept(CorrelationVisitor<T> visitor) {
return visitor.visitEscapeCorrelation(this);
}
}