@Override
public AbstractState join(AbstractState successor, AbstractState reached) {
Pair<OctagonState, OctagonState> shrinkedStates =
getShrinkedStates((OctagonState) successor, (OctagonState) reached);
Octagon newOctagon =
shrinkedStates
.getFirst()
.getOctagon()
.getManager()
.union(shrinkedStates.getFirst().getOctagon(), shrinkedStates.getSecond().getOctagon());
// TODO this should not be necessary however it occurs that a widened state is bottom
if (shrinkedStates.getFirst().getOctagon().getManager().isEmpty(newOctagon)) {
throw new AssertionError("bottom state occured where it should not be");
}
OctagonState newState =
new OctagonState(
newOctagon,
shrinkedStates.getFirst().getVariableToIndexMap(),
shrinkedStates.getFirst().getVariableToTypeMap(),
logger);
if (((OctagonState) reached).isLoopHead()) {
newState = newState.asLoopHead();
}
if (newState.equals(reached)) {
return reached;
} else if (newState.equals(successor)) {
return successor;
} else {
return newState;
}
}
public AbstractState widening(OctagonState successorOct, OctagonState reachedOct) {
Pair<OctagonState, OctagonState> shrinkedStates = getShrinkedStates(successorOct, reachedOct);
successorOct = shrinkedStates.getFirst();
reachedOct = shrinkedStates.getSecond();
Octagon newOctagon =
reachedOct
.getOctagon()
.getManager()
.widening(reachedOct.getOctagon(), successorOct.getOctagon());
// TODO this should not be necessary however it occurs that a widened state is bottom
if (reachedOct.getOctagon().getManager().isEmpty(newOctagon)) {
newOctagon =
reachedOct
.getOctagon()
.getManager()
.union(reachedOct.getOctagon(), successorOct.getOctagon());
logger.log(
Level.WARNING,
"bottom state occured where it should not be, using union instead of widening as a fallback");
if (reachedOct.getOctagon().getManager().isEmpty(newOctagon)) {
throw new AssertionError("bottom state occured where it should not be");
}
}
OctagonState newState =
new OctagonState(
newOctagon,
successorOct.getVariableToIndexMap(),
successorOct.getVariableToTypeMap(),
logger);
if (reachedOct.isLoopHead()) {
newState = newState.asLoopHead();
}
if (newState.equals(successorOct)) {
return successorOct;
} else if (newState.equals(reachedOct)) {
return reachedOct;
} else {
return newState;
}
}
