def generate_special_paths(con_loc, ppc_str):
parser = SmtLibParser()
special_list = []
script = parser.get_script(cStringIO(ppc_str))
path_condition = script.get_last_formula()
angelic_count = int(len(re.findall("angelic!(.+?)!0", str(path_condition.serialize()))) / 4)
if angelic_count > 1:
false_path = generate_false_path(path_condition)
true_path = generate_true_path(path_condition)
if true_path:
special_list.append((con_loc, true_path, len(str(true_path.serialize()))))
if false_path:
special_list.append((con_loc, false_path, len(str(false_path.serialize()))))
return special_list
def generate_flipped_path(ppc):
"""
This function will check if a selected path is feasible
ppc : partial path conditoin at chosen control loc
chosen_control_loc: branch location selected for flip
returns satisfiability of the negated path
"""
parser = SmtLibParser()
script = parser.get_script(cStringIO(ppc))
formula = script.get_last_formula()
prefix = formula.arg(0)
constraint = formula.arg(1)
new_path = And(prefix, Not(constraint))
assert str(new_path.serialize()) != str(formula.serialize())
return new_path
def generate_path_for_negation():
constraint_list = []
parser = SmtLibParser()
emitter.normal("\tgenerating path for negation of patch constraint")
for control_loc, sym_path in values.LIST_PPC:
if control_loc == values.CONF_LOC_PATCH:
script = parser.get_script(cStringIO(sym_path))
formula = script.get_last_formula()
patch_constraint = formula
if formula.is_and():
patch_constraint = formula.arg(1)
constraint_list.append(patch_constraint.serialize())
if not constraint_list:
return None
last_sym_path = values.LAST_PPC_FORMULA
# script = parser.get_script(cStringIO(last_sym_path))
# formula = script.get_last_formula()
negated_path = None
while constraint_list:
constraint = last_sym_path
if last_sym_path.is_and():
constraint = last_sym_path.arg(1)
constraint_str = constraint.serialize()
if constraint_str in constraint_list:
constraint_list.remove(constraint_str)
constraint = Not(constraint)
if negated_path is None:
negated_path = constraint
else:
negated_path = And(negated_path, constraint)
if last_sym_path.is_and():
last_sym_path = last_sym_path.arg(0)
else:
break
negated_path = And(negated_path, last_sym_path)
return negated_path
def generate_formula(formula_str):
parser = SmtLibParser()
script = parser.get_script(cStringIO(formula_str))
formula = script.get_last_formula()
return formula