def refine(self, v):
logging.debug("Refining: " + str(v))
if v.location not in self.cfa.panic:
return
if models(v.label, BoolVal(False)):
return
v_pi, u_pi = v.ancestors_path, v.transition_path
assert (len(v_pi) == len(u_pi) + 1)
u_pi_, times = timeshift(u_pi)
assert (len(u_pi) == len(u_pi_))
try:
a_hat = z3.sequence_interpolant(u_pi_)
except z3.ModelRef as model:
self.mark_unsafe(v, model)
return
a_hat.push(BoolVal(False))
assert (len(v_pi) == len(a_hat) + 1)
for i in range(len(a_hat)):
phi = untimeshift(a_hat[i], times)
if not models(v_pi[i + 1].label, phi):
for (x, y) in self.covering.copy():
if y == v_pi[i + 1]:
self.covering.discard((x, y))
v_pi[i + 1].label = z3.simplify(And(v_pi[i + 1].label, phi))
def sequence_interpolant(self, formulas):
self._check_logic(formulas)
zf = [self.converter.convert(f) for f in formulas]
try:
itp = z3.sequence_interpolant(zf)
pysmt_res = [self.converter.back(f) for f in itp]
except z3.ModelRef:
pysmt_res = None
return pysmt_res
def sequence_interpolant(self, formulas):
self._check_logic(formulas)
zf = [self.converter.convert(f) for f in formulas]
try:
itp = z3.sequence_interpolant(zf)
pysmt_res = [self.converter.back(f) for f in itp]
except z3.ModelRef:
pysmt_res = None
return pysmt_res