public void calculateOutSet(Unit u, BoundedFlowSet inSet, BoundedFlowSet outSet) {
// If the def set is a subset of the in set, then out = in \ impure use, else
// out = (in union def) \ use
BoundedFlowSet defSet = defSetMap.get(u);
BoundedFlowSet inComplement = (BoundedFlowSet) inSet.clone();
inComplement.complement();
inComplement.intersection(defSet);
if (inComplement.size() == 0) {
inSet.copy(outSet);
outSet.difference(useSetMap.get(u));
} else {
inSet.union(defSet, outSet);
outSet.difference(useSetMap.get(u));
}
}
public FaintVariableAnalysis(Body body) {
Chain<Local> locals = body.getLocals();
allVariables = new CollectionFlowUniverse<Local>(locals);
universalSet = new ArrayPackedSet(allVariables);
for (Local l : locals) universalSet.add(l);
useSetMap = new HashMap<Unit, BoundedFlowSet>();
defSetMap = new HashMap<Unit, BoundedFlowSet>();
UnitGraph graph = new BriefUnitGraph(body);
for (Unit u : graph) {
BoundedFlowSet defSet = new ArrayPackedSet(allVariables);
BoundedFlowSet useSet = new ArrayPackedSet(allVariables);
for (ValueBox v : u.getDefBoxes()) {
// Only do this for locals. We're not going to even try to handle anything
// other than locals.
if (v.getValue() instanceof Local) {
defSet.add(v.getValue());
}
}
for (ValueBox v : u.getUseBoxes()) {
// Only do this for locals. We're not going to even try to handle anything
// other than locals.
if (v.getValue() instanceof Local) {
useSet.add(v.getValue());
}
}
defSetMap.put(u, defSet);
useSetMap.put(u, useSet);
}
}
public void mergeOutSets(List<BoundedFlowSet> outSets, BoundedFlowSet inSet) {
// Take the intersection of the out sets as the in set.
for (BoundedFlowSet set : outSets) inSet.intersection(set);
}
public BoundedFlowSet createOutSet(Unit u) {
// Initial value for the out set is the universal set
return (BoundedFlowSet) universalSet.clone();
}