soot.toolkits.scalar.SmartLocalDefsPool Maven / Gradle / Ivy
package soot.toolkits.scalar;
/*-
* #%L
* Soot - a J*va Optimization Framework
* %%
* Copyright (C) 2015 Eric Bodden and others
* %%
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License as
* published by the Free Software Foundation, either version 2.1 of the
* License, or (at your option) any later version.
*
* This program 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 Lesser Public License for more details.
*
* You should have received a copy of the GNU General Lesser Public
* License along with this program. If not, see
* .
* #L%
*/
import com.google.common.collect.Maps;
import java.util.Map;
import soot.Body;
import soot.G;
import soot.Singletons;
import soot.toolkits.graph.ExceptionalUnitGraph;
import soot.toolkits.graph.UnitGraph;
/**
* This class implements a pool for {@link SmartLocalDefs} instances. This is useful, as these analyses are expensive to
* compute. A {@link SmartLocalDefs} instance requires a {@link UnitGraph} (usually a {@link ExceptionalUnitGraph}), and
* creating these repeatedly, and applying the {@link SmartLocalDefs} analysis repeatedly costs time. Therefore in this class
* we pool these instances in cases in which the respective body is still the same.
*
* @author Eric Bodden
*/
public class SmartLocalDefsPool {
protected Map> pool = Maps.newHashMap();
/**
* This method returns a fresh instance of a {@link SmartLocalDefs} analysis, based on a freshly created
* {@link ExceptionalUnitGraph} for b, with standard parameters. If the body b's modification count has not changed since
* the last time such an analysis was requested for b, then the previously created analysis is returned instead.
*
* @see Body#getModificationCount()
*/
public SmartLocalDefs getSmartLocalDefsFor(Body b) {
Pair modCountAndSLD = pool.get(b);
if (modCountAndSLD != null && modCountAndSLD.o1.longValue() == b.getModificationCount()) {
return modCountAndSLD.o2;
} else {
ExceptionalUnitGraph g = new ExceptionalUnitGraph(b);
SmartLocalDefs newSLD = new SmartLocalDefs(g, new SimpleLiveLocals(g));
pool.put(b, new Pair(b.getModificationCount(), newSLD));
return newSLD;
}
}
public void clear() {
pool.clear();
}
public static SmartLocalDefsPool v() {
return G.v().soot_toolkits_scalar_SmartLocalDefsPool();
}
public SmartLocalDefsPool(Singletons.Global g) {
}
public void invalidate(Body b) {
pool.remove(b);
}
}