@Override
public int hashCode() {
int hash = 1;
hash = hash * Utils.HASH_PRIME + term.hashCode();
hash = hash * Utils.HASH_PRIME + lookups.hashCode();
hash = hash * Utils.HASH_PRIME + constraint.hashCode();
return hash;
}
@Override
public boolean equals(Object object) {
if (this == object) {
return true;
}
if (!(object instanceof ConstrainedTerm)) {
return false;
}
ConstrainedTerm constrainedTerm = (ConstrainedTerm) object;
return term.equals(constrainedTerm.term)
&& lookups.equals(constrainedTerm.lookups)
&& constraint.equals(constrainedTerm.constraint);
}
public SymbolicConstraint matchImplies(ConstrainedTerm constrainedTerm) {
SymbolicConstraint unificationConstraint =
new SymbolicConstraint(constrainedTerm.termContext());
unificationConstraint.add(term, constrainedTerm.term);
unificationConstraint.simplify();
if (unificationConstraint.isFalse() || !unificationConstraint.isSubstitution()) {
return null;
}
SymbolicConstraint implicationConstraint =
new SymbolicConstraint(constrainedTerm.termContext());
implicationConstraint.addAll(unificationConstraint);
implicationConstraint.addAll(constrainedTerm.lookups);
implicationConstraint.addAll(constrainedTerm.constraint);
implicationConstraint.simplify();
unificationConstraint.addAll(constraint);
unificationConstraint.simplify();
if (!unificationConstraint.implies(implicationConstraint)) {
return null;
}
unificationConstraint.addAll(implicationConstraint);
return unificationConstraint;
}
public Collection<SymbolicConstraint> unify(ConstrainedTerm constrainedTerm) {
if (!term.kind.equals(constrainedTerm.term.kind)) {
return Collections.emptyList();
}
SymbolicConstraint unificationConstraint =
new SymbolicConstraint(constrainedTerm.termContext());
unificationConstraint.add(term, constrainedTerm.term());
unificationConstraint.simplify();
if (unificationConstraint.isFalse()) {
return Collections.emptyList();
}
Collection<SymbolicConstraint> constraints = new ArrayList<SymbolicConstraint>();
for (SymbolicConstraint solution : unificationConstraint.getMultiConstraints()) {
if (SymbolicConstraint.TruthValue.FALSE == solution.addAll(constrainedTerm.lookups)) continue;
if (SymbolicConstraint.TruthValue.FALSE == solution.addAll(constrainedTerm.constraint))
continue;
if (SymbolicConstraint.TruthValue.FALSE == solution.addAll(constraint)) continue;
solution.simplify();
if (solution.isFalse()) {
continue;
}
if (solution.checkUnsat()) {
continue;
}
constraints.add(solution);
}
return constraints;
}