def find_predecessor(
self, pre_frame: Frame, current_phase: Phase, diag: Diagram
) -> Tuple[z3.CheckSatResult, Union[Optional[MySet[int]], Tuple[
PhaseTransition, Tuple[Phase, Diagram]]]]:
t = self.solver.get_translator(KEY_NEW, KEY_OLD)
if utils.args.use_z3_unsat_cores:
core: Optional[MySet[int]] = MySet()
else:
core = None
with self.solver:
with self.solver.mark_assumptions_necessary():
self.solver.add(diag.to_z3(t))
transitions_into = self.automaton.transitions_to_grouped_by_src(
current_phase)
for src in self._predecessor_precedence(
current_phase, list(transitions_into.keys())):
transitions = transitions_into[src]
assert transitions
utils.logger.debug(
"check predecessor of %s from %s by %s" %
(current_phase.name(), src.name(), transitions))
(sat_res, pre_diag) = self.find_predecessor_from_src_phase(
t, pre_frame, src, transitions, diag, core)
if sat_res == z3.unsat:
continue
return (sat_res, pre_diag)
if utils.args.use_z3_unsat_cores:
assert core is not None
ret_core: Optional[MySet[int]] = MySet(sorted(core))
else:
ret_core = None
return (z3.unsat, ret_core)
def augment_core_for_init(self, p: Phase, diag: Diagram,
core: Optional[MySet[int]]) -> None:
if core is None or not utils.args.use_z3_unsat_cores:
return
t = self.solver.get_translator(KEY_ONE)
with self.solver:
for init in self.fs[0].summary_of(p):
self.solver.add(t.translate_expr(init))
self.solver.add(diag.to_z3(t))
res = self.solver.check(diag.trackers)
assert res == z3.unsat
uc = self.solver.unsat_core()
# if utils.logger.isEnabledFor(logging.DEBUG):
# utils.logger.debug('uc')
# utils.logger.debug(str(sorted(uc, key=lambda y: y.decl().name())))
# utils.logger.debug('assertions')
# utils.logger.debug(str(self.solver.assertions()))
res = self.solver.check([diag.trackers[i] for i in core])
if res == z3.unsat:
utils.logger.debug(
'augment_core_for_init: existing core sufficient')
return
for x in sorted(uc, key=lambda y: y.decl().name()):
assert isinstance(x, z3.ExprRef)
core.add(int(x.decl().name()[1:]))
if utils.logger.isEnabledFor(logging.DEBUG):
utils.logger.debug('augment_core_for_init: new core')
utils.logger.debug(str(sorted(core)))