def test_implies(self):
a, b, c, d = (Symbol(x) for x in "abcd")
f = Implies(Iff(a, b), Iff(c, d))
conv = CNFizer()
cnf = conv.convert_as_formula(f)
self.assertValid(Implies(cnf, f), logic=QF_BOOL)
def test_implies(self):
a,b,c,d = (Symbol(x) for x in "abcd")
f = Implies(Iff(a, b), Iff(c, d))
conv = CNFizer()
cnf = conv.convert_as_formula(f)
self.assertValid(Implies(cnf, f), logic=QF_BOOL)
def __init__(self, environment, logic, **options):
Solver.__init__(self, environment=environment, logic=logic, **options)
self.mgr = environment.formula_manager
self.pico = picosat.picosat_init()
self.converter = None
self.cnfizer = CNFizer(environment=environment)
self.latest_model = None
self._var_ids = {}
def do_examples(self, logic):
conv = CNFizer()
for example in EXAMPLE_FORMULAS:
if example.logic != logic:
continue
cnf = conv.convert_as_formula(example.expr)
self.assertValid(Implies(cnf, example.expr), logic=logic)
res = is_sat(cnf, logic=logic)
self.assertEqual(res, example.is_sat)
def do_examples(self, logic):
conv = CNFizer()
for example in get_example_formulae():
if example.logic != logic:
continue
cnf = conv.convert_as_formula(example.expr)
self.assertValid(Implies(cnf, example.expr), logic=logic)
res = is_sat(cnf, logic=logic)
self.assertEqual(res, example.is_sat)
def _smtlib_cnf(self, filename, logic, res_is_sat):
reset_env()
conv = CNFizer()
smtfile = os.path.join(SMTLIB_DIR, filename)
assert os.path.exists(smtfile)
expr = get_formula_fname(smtfile)
if not logic.quantifier_free:
with self.assertRaises(NotImplementedError):
conv.convert_as_formula(expr)
return
cnf = conv.convert_as_formula(expr)
self.assertValid(Implies(cnf, expr), logic=logic)
res = is_sat(cnf, logic=logic)
self.assertEqual(res, res_is_sat)
def _smtlib_cnf(self, filename, logic, res_is_sat):
reset_env()
conv = CNFizer()
smtfile = os.path.join(SMTLIB_DIR, filename)
assert os.path.exists(smtfile)
expr = get_formula_fname(smtfile)
if not logic.quantifier_free:
with self.assertRaises(NotImplementedError):
conv.convert_as_formula(expr)
return
cnf = conv.convert_as_formula(expr)
self.assertValid(Implies(cnf, expr), logic=logic)
res = is_sat(cnf, logic=logic)
self.assertEqual(res, res_is_sat)
def __init__(self, environment, logic, user_options):
Solver.__init__(self,
environment=environment,
logic=logic,
user_options=user_options)
self.mgr = environment.formula_manager
self.pico = picosat.picosat_init()
self.converter = None
self.cnfizer = CNFizer(environment=environment)
self.latest_model = None
self._var_ids = {}
def __init__(self, environment, logic, **options):
Solver.__init__(self,
environment=environment,
logic=logic,
**options)
self.mgr = environment.formula_manager
self.pico = picosat.picosat_init()
self.converter = None
self.cnfizer = CNFizer(environment=environment)
self.latest_model = None
self._var_ids = {}
self._log_file_handler = None
# Initialize
self.options(self)
class PicosatSolver(Solver):
"""PicoSAT solver"""
LOGICS = [ pysmt.logics.QF_BOOL ]
def __init__(self, environment, logic, user_options):
Solver.__init__(self,
environment=environment,
logic=logic,
user_options=user_options)
self.mgr = environment.formula_manager
self.pico = picosat.picosat_init()
self.converter = None
self.cnfizer = CNFizer(environment=environment)
self.latest_model = None
self._var_ids = {}
def _get_var_id(self, symbol):
if not symbol.is_symbol(types.BOOL):
raise NotImplementedError("No theory terms are supported in PicoSAT")
if symbol in self._var_ids:
return self._var_ids[symbol]
else:
vid = picosat.picosat_inc_max_var(self.pico)
self._var_ids[symbol] = vid
return vid
@clear_pending_pop
def reset_assertions(self):
picosat.picosat_reset(self.pico)
self.pico = picosat.picosat_init()
@clear_pending_pop
def declare_variable(self, var):
# no need to declare variables
pass
def _get_pico_lit(self, lit):
mult = 1
var = lit
if lit.is_not():
mult = -1
var = lit.arg(0)
vid = self._get_var_id(var)
return vid * mult
@clear_pending_pop
@catch_conversion_error
def add_assertion(self, formula, named=None):
# First, we get rid of True/False constants
formula = formula.simplify()
if formula.is_false():
picosat.picosat_add(self.pico, 0)
elif not formula.is_true():
cnf = self.cnfizer.convert(formula)
self._add_cnf_assertion(cnf)
def _add_cnf_assertion(self, cnf):
for clause in cnf:
for lit in clause:
v = self._get_pico_lit(lit)
picosat.picosat_add(self.pico, v)
picosat.picosat_add(self.pico, 0)
@clear_pending_pop
@catch_conversion_error
def solve(self, assumptions=None):
if assumptions is not None:
cnf = []
for a in assumptions:
cnf += self.cnfizer.convert(a)
missing = []
for clause in cnf:
if len(clause) == 1:
v = self._get_pico_lit(next(iter(clause)))
picosat.picosat_assume(self.pico, v)
else:
missing.append(clause)
if len(missing) > 0:
self.push()
self._add_cnf_assertion(missing)
self.pending_pop = True
res = picosat.picosat_sat(self.pico, -1)
if res == picosat.PICOSAT_SATISFIABLE:
self.latest_model = self.get_model()
return True
else:
self.latest_model = None
return False
def get_value(self, item):
if self.latest_model is None:
self.get_model()
return self.latest_model.get_value(item)
def get_model(self):
assignment = {}
for var, vid in iteritems(self._var_ids):
v = picosat.picosat_deref(self.pico, vid)
if v == 0:
assert False
value = self.mgr.Bool(v == 1)
assignment[var] = value
return EagerModel(assignment=assignment,
environment=self.environment)
@clear_pending_pop
def push(self, levels=1):
for _ in xrange(levels):
picosat.picosat_push(self.pico)
@clear_pending_pop
def pop(self, levels=1):
for _ in xrange(levels):
picosat.picosat_pop(self.pico)
def _exit(self):
picosat.picosat_reset(self.pico)
class PicosatSolver(Solver):
"""PicoSAT solver"""
LOGICS = [pysmt.logics.QF_BOOL]
OptionsClass = PicosatOptions
def __init__(self, environment, logic, **options):
Solver.__init__(self, environment=environment, logic=logic, **options)
self.mgr = environment.formula_manager
self.pico = picosat.picosat_init()
self.converter = None
self.cnfizer = CNFizer(environment=environment)
self.latest_model = None
self._var_ids = {}
self._log_file_handler = None
# Initialize
self.options(self)
def _get_var_id(self, symbol):
if not symbol.is_symbol(types.BOOL):
raise ConvertExpressionError(
"No theory terms are supported in PicoSAT")
if symbol in self._var_ids:
return self._var_ids[symbol]
else:
vid = picosat.picosat_inc_max_var(self.pico)
self._var_ids[symbol] = vid
return vid
@clear_pending_pop
def reset_assertions(self):
picosat.picosat_flushout(self._log_file_handler)
picosat.picosat_reset(self.pico)
self.pico = picosat.picosat_init()
self.options(self)
@clear_pending_pop
def declare_variable(self, var):
raise NotImplementedError
def _get_pico_lit(self, lit):
mult = 1
var = lit
if lit.is_not():
mult = -1
var = lit.arg(0)
vid = self._get_var_id(var)
return vid * mult
@clear_pending_pop
@catch_conversion_error
def add_assertion(self, formula, named=None):
# First, we get rid of True/False constants
formula = formula.simplify()
if formula.is_false():
picosat.picosat_add(self.pico, 0)
elif not formula.is_true():
cnf = self.cnfizer.convert(formula)
self._add_cnf_assertion(cnf)
def _add_cnf_assertion(self, cnf):
for clause in cnf:
for lit in clause:
v = self._get_pico_lit(lit)
picosat.picosat_add(self.pico, v)
picosat.picosat_add(self.pico, 0)
@clear_pending_pop
@catch_conversion_error
def solve(self, assumptions=None):
if assumptions is not None:
cnf = []
for a in assumptions:
cnf += self.cnfizer.convert(a)
missing = []
for clause in cnf:
if len(clause) == 1:
v = self._get_pico_lit(next(iter(clause)))
picosat.picosat_assume(self.pico, v)
else:
missing.append(clause)
if len(missing) > 0:
self.push()
self._add_cnf_assertion(missing)
self.pending_pop = True
res = picosat.picosat_sat(self.pico, -1)
if res == picosat.PICOSAT_SATISFIABLE:
self.latest_model = self.get_model()
return True
else:
self.latest_model = None
return False
def get_value(self, item):
if self.latest_model is None:
self.get_model()
return self.latest_model.get_value(item)
def get_model(self):
assignment = {}
for var, vid in iteritems(self._var_ids):
v = picosat.picosat_deref(self.pico, vid)
if v == 0:
assert False
value = self.mgr.Bool(v == 1)
assignment[var] = value
return EagerModel(assignment=assignment, environment=self.environment)
@clear_pending_pop
def push(self, levels=1):
for _ in xrange(levels):
picosat.picosat_push(self.pico)
@clear_pending_pop
def pop(self, levels=1):
for _ in xrange(levels):
picosat.picosat_pop(self.pico)
def _exit(self):
picosat.picosat_flushout(self._log_file_handler)
picosat.picosat_reset(self.pico)
