def _isVar(self, elem):
return any([
z3.is_int_value(z3.simplify(elem)),
z3.is_rational_value(z3.simplify(elem)),
z3.is_algebraic_value(z3.simplify(elem)),
is_const(z3.simplify(elem))
])
def _is_literal(z3ast):
if z3.is_int(z3ast):
return z3.is_int_value(z3ast)
if z3.is_bool(z3ast):
return z3.is_true(z3ast) or z3.is_false(z3ast)
if z3ast.sort_kind() == z3.Z3_UNINTERPRETED_SORT:
return z3.is_const(z3ast) and '!' in str(z3ast)
raise NotImplementedError('Don\'t know how to literal-check %s' % z3ast)
def _is_literal(z3ast):
if z3.is_int(z3ast):
return z3.is_int_value(z3ast)
if z3.is_bool(z3ast):
return z3.is_true(z3ast) or z3.is_false(z3ast)
if z3ast.sort_kind() == z3.Z3_UNINTERPRETED_SORT:
return z3.is_const(z3ast) and '!' in str(z3ast)
raise NotImplementedError('Don\'t know how to literal-check %s' % z3ast)
def is_bool_or_int_value(value):
if z3.is_int_value(value):
return True
if value.sort() == z3.BoolSort():
if z3.is_true(value) or z3.is_false(value):
return True
else:
return False
def collect_numerals(z3term):
if z3.is_int_value(z3term) or z3.is_bv_value(z3term):
yield z3term
elif z3.is_app_of(z3term, z3.Z3_OP_ITE):
for z in collect_numerals(z3term.arg(1)):
yield z
for z in collect_numerals(z3term.arg(2)):
yield z
def pp_app(self, a, d, xs):
if z3.is_int_value(a):
return self.pp_int(a)
elif z3.is_rational_value(a):
return self.pp_rational(a)
elif z3.is_algebraic_value(a):
return self.pp_algebraic(a)
elif z3.is_bv_value(a):
return self.pp_bv(a)
elif z3.is_finite_domain_value(a):
return self.pp_fd(a)
elif z3.is_fprm_value(a):
return self.pp_fprm_value(a)
elif z3.is_fp_value(a):
return self.pp_fp_value(a)
elif z3.is_fp(a):
return self.pp_fp(a, d, xs)
elif z3.is_string_value(a):
return self.pp_string(a)
elif z3.is_const(a):
return self.pp_const(a)
else:
f = a.decl()
k = f.kind()
if k == Z3_OP_POWER:
return self.pp_power(a, d, xs)
elif k == Z3_OP_DISTINCT:
return self.pp_distinct(a, d, xs)
elif k == Z3_OP_SELECT:
return self.pp_select(a, d, xs)
elif k == Z3_OP_SIGN_EXT or k == Z3_OP_ZERO_EXT or k == Z3_OP_REPEAT:
return self.pp_unary_param(a, d, xs)
elif k == Z3_OP_EXTRACT:
return self.pp_extract(a, d, xs)
elif k == Z3_OP_RE_LOOP:
return self.pp_loop(a, d, xs)
elif k == Z3_OP_DT_IS:
return self.pp_is(a, d, xs)
elif k == Z3_OP_ARRAY_MAP:
return self.pp_map(a, d, xs)
elif k == Z3_OP_CONST_ARRAY:
return self.pp_K(a, d, xs)
elif k == Z3_OP_PB_AT_MOST:
return self.pp_atmost(a, d, f, xs)
elif k == Z3_OP_PB_LE:
return self.pp_pbcmp(a, d, f, xs)
elif k == Z3_OP_PB_GE:
return self.pp_pbcmp(a, d, f, xs)
elif k == Z3_OP_PB_EQ:
return self.pp_pbcmp(a, d, f, xs)
elif z3.is_pattern(a):
return self.pp_pattern(a, d, xs)
elif self.is_infix(k):
return self.pp_infix(a, d, xs)
elif self.is_unary(k):
return self.pp_unary(a, d, xs)
else:
return self.pp_prefix(a, d, xs)
def convert(t, values):
if z3.is_int_value(t):
return t.as_long()
if z3.is_app(t):
func = globals()[t.decl().name()]
return func(
*[convert(t.arg(i), values) for i in range(t.num_args())])
elif z3.is_var(t):
return values[z3.get_var_index(t)]
def pp_app(self, a, d, xs):
if z3.is_int_value(a):
return self.pp_int(a)
elif z3.is_rational_value(a):
return self.pp_rational(a)
elif z3.is_algebraic_value(a):
return self.pp_algebraic(a)
elif z3.is_bv_value(a):
return self.pp_bv(a)
elif z3.is_finite_domain_value(a):
return self.pp_fd(a)
elif z3.is_fprm_value(a):
return self.pp_fprm_value(a)
elif z3.is_fp_value(a):
return self.pp_fp_value(a)
elif z3.is_fp(a):
return self.pp_fp(a, d, xs)
elif z3.is_string_value(a):
return self.pp_string(a)
elif z3.is_const(a):
return self.pp_const(a)
else:
f = a.decl()
k = f.kind()
if k == Z3_OP_POWER:
return self.pp_power(a, d, xs)
elif k == Z3_OP_DISTINCT:
return self.pp_distinct(a, d, xs)
elif k == Z3_OP_SELECT:
return self.pp_select(a, d, xs)
elif k == Z3_OP_SIGN_EXT or k == Z3_OP_ZERO_EXT or k == Z3_OP_REPEAT:
return self.pp_unary_param(a, d, xs)
elif k == Z3_OP_EXTRACT:
return self.pp_extract(a, d, xs)
elif k == Z3_OP_DT_IS:
return self.pp_is(a, d, xs)
elif k == Z3_OP_ARRAY_MAP:
return self.pp_map(a, d, xs)
elif k == Z3_OP_CONST_ARRAY:
return self.pp_K(a, d, xs)
elif k == Z3_OP_PB_AT_MOST:
return self.pp_atmost(a, d, f, xs)
elif k == Z3_OP_PB_LE:
return self.pp_pbcmp(a, d, f, xs)
elif k == Z3_OP_PB_GE:
return self.pp_pbcmp(a, d, f, xs)
elif k == Z3_OP_PB_EQ:
return self.pp_pbcmp(a, d, f, xs)
elif z3.is_pattern(a):
return self.pp_pattern(a, d, xs)
elif self.is_infix(k):
return self.pp_infix(a, d, xs)
elif self.is_unary(k):
return self.pp_unary(a, d, xs)
else:
return self.pp_prefix(a, d, xs)
def model_to_val(m, var):
p = m[var]
if is_int_value(p):
return float(p.as_long())
if is_algebraic_value(p):
p = p.approx(5) # Precise to 5 decimals
if is_rational_value(p):
x = float(p.numerator_as_long()) / \
float(p.denominator_as_long())
return x
def collect_consts(smt_expr):
"""Returns list of all constants (as ExprRef instances) that appear in the given expression"""
assert (isinstance(smt_expr, z3.ExprRef))
non_unique_res = expr_fold(smt_expr, lambda t: [t]
if not z3.is_int_value(t) else [],
lambda _, cs: utils.flatten(cs))
for c in non_unique_res:
assert (z3.is_const(c))
# Leaving the following in, in case conversion breaks again with strange z3 exceptions...
#logger.info([c.__class__ for c in non_unique_res])
res = set(non_unique_res)
#logger.info("Consts in expr: {}".format(res))
return [c for c in res if str(c) not in keywords]
def rec(e):
if isinstance(e, z3.QuantifierRef):
for n in range(e.num_vars()):
mkvar(e.var_name(n), e.var_sort(n))
elif z3.is_algebraic_value(e) or \
z3.is_bv_value(e) or \
z3.is_int_value(e) or \
z3.is_rational_value(e):
pass
elif z3.is_const(e):
mkvar(str(e), e.sort())
for sub in e.children():
rec(sub)
def to_python(some_number):
if isinstance(some_number, numbers.Number):
return some_number
some_number = z3.simplify(some_number)
if z3.is_algebraic_value(some_number):
some_number = some_number.approx(config.approx)
if z3.is_int_value(some_number):
return some_number.as_long()
else:
try:
return float(some_number.numerator_as_long()) / float(
some_number.denominator_as_long())
except Exception:
return str(some_number) # last resort, return as string
def val(self, exp):
'''Evaluate a z3 ref to a python value based on this solution.
'''
v = self.model.eval(exp)
if z3.is_true(v):
return True
if z3.is_false(v):
return False
if z3.is_algebraic_value(v):
v = v.approx(20)
if z3.is_int_value(v):
return v.as_long()
if z3.is_rational_value(v):
return v.numerator_as_long() / v.denominator_as_long()
return z3.is_true(v)
def to_python(some_number):
raise DeprecationWarning("use config.to_python instead")
if isinstance(some_number, (int, float, str, bool)):
return some_number
some_number = z3.simplify(some_number)
if z3.is_algebraic_value(some_number):
some_number = some_number.approx(config.approx)
if z3.is_int_value(some_number):
return some_number.as_long()
else:
try:
return float(some_number.numerator_as_long()) / float(
some_number.denominator_as_long())
except Exception:
return str(some_number) # last resort
def get_py_val_from_z3_val(z3_result):
if z3_result is not None:
if z3.is_int_value(z3_result):
return z3_result.as_long()
elif z3.is_real(z3_result):
return float(z3_result.numerator_as_long()) / float(
z3_result.denominator_as_long())
elif z3.is_true(z3_result):
return True
elif z3.is_false(z3_result):
return False
elif z3.is_string_value(z3_result):
return z3_result.as_string()
else:
raise NotImplementedError(
"Z3 model result other than int, real, bool, string is not supported yet!"
)
def z3ToPoint(self, point):
res = []
# get the variables corresponding to the axis names
for idx, i in enumerate(self.axis_names):
locals()[i] = Globals.z3variables[i]
if i in Globals.z3types: # non-numeric points -> coord to value
value = Globals.z3types[i][point[locals()[i]].as_long()]
elif None == point[locals()[i]]:
info("no value for %s, take %r (incomplete model)" %
(self.axis_names[idx], self.axis_val_ranges[idx][0]))
value = self.axis_val_ranges[idx][0]
elif z3.is_int_value(point[locals()[i]]):
value = point[locals()[i]].as_long()
elif z3.is_true(point[locals()[i]]) or z3.is_false(
point[locals()[i]]):
value = z3.is_true(point[locals()[i]])
res.append(value)
return res
def mk_const(self, c):
if z3.is_int_value(c):
return ii(c.as_long())
if z3.is_rational_value(c):
# TODO: what should we convert a rational to?
return rr(Fraction(c.numerator_as_long(), \
c.denominator_as_long()))
elif z3.is_true(c):
return true
elif z3.is_false(c):
return false
else:
try:
return self.context.decls[str(c)]
except KeyError:
#Constant is not found in the context
typ = self.mk_sort(c.sort())
return const(str(c), typ)
def mk_const(self, c):
if z3.is_int_value(c):
return ii(c.as_long())
if z3.is_rational_value(c):
# TODO: what should we convert a rational to?
return rr(Fraction(c.numerator_as_long(), \
c.denominator_as_long()))
elif z3.is_true(c):
return true
elif z3.is_false(c):
return false
else:
try:
return self.context.decls[str(c)]
except KeyError:
#Constant is not found in the context
typ = self.mk_sort(c.sort())
return const(str(c), typ)
def get_value(r):
# https://stackoverflow.com/questions/12598408/z3-python-getting-python-values-from-model/12600208
"""
Convert from Z3 to python values.
"""
if z3.is_true(r):
return z3.is_true(r)
elif z3.is_false(r):
return z3.is_false(r)
elif z3.is_int_value(r):
return r.as_long()
elif z3.is_algebraic_value(r):
return round(num(r.approx(15)), 10)
elif z3.is_rational_value(r):
return r.as_decimal(20)
elif r is None:
None
else:
return num(r)
def pp_app(self, a, d, xs):
if z3.is_int_value(a):
return self.pp_int(a)
elif z3.is_rational_value(a):
return self.pp_rational(a)
elif z3.is_algebraic_value(a):
return self.pp_algebraic(a)
elif z3.is_bv_value(a):
return self.pp_bv(a)
elif z3.is_fprm_value(a):
return self.pp_fprm_value(a)
elif z3.is_fp_value(a):
return self.pp_fp_value(a)
elif z3.is_fp(a):
return self.pp_fp(a, d, xs)
elif z3.is_const(a):
return self.pp_const(a)
else:
f = a.decl()
k = f.kind()
if k == Z3_OP_POWER:
return self.pp_power(a, d, xs)
elif k == Z3_OP_DISTINCT:
return self.pp_distinct(a, d, xs)
elif k == Z3_OP_SELECT:
return self.pp_select(a, d, xs)
elif k == Z3_OP_SIGN_EXT or k == Z3_OP_ZERO_EXT or k == Z3_OP_REPEAT:
return self.pp_unary_param(a, d, xs)
elif k == Z3_OP_EXTRACT:
return self.pp_extract(a, d, xs)
elif k == Z3_OP_ARRAY_MAP:
return self.pp_map(a, d, xs)
elif k == Z3_OP_CONST_ARRAY:
return self.pp_K(a, d, xs)
elif z3.is_pattern(a):
return self.pp_pattern(a, d, xs)
elif self.is_infix(k):
return self.pp_infix(a, d, xs)
elif self.is_unary(k):
return self.pp_unary(a, d, xs)
else:
return self.pp_prefix(a, d, xs)
def coerceTypesIfPossible(var, other_var):
if z3.is_or(other_var) and not z3.is_bool(var):
other_var = transformNonBooleanLazyEvaluations(other_var)
if z3.is_or(var) and not z3.is_bool(other_var):
var = transformNonBooleanLazyEvaluations(var)
if z3.is_and(other_var) and not z3.is_bool(var):
other_var = transformNonBooleanLazyEvaluations(other_var)
if z3.is_and(var) and not z3.is_bool(other_var):
var = transformNonBooleanLazyEvaluations(var)
if var.decl().kind() == z3.Z3_OP_UNINTERPRETED:
if z3.is_bool(other_var) and not z3.is_bool(var):
infered_types[str(var)] = 'boolean'
return z3.Bool(str(var)), other_var
if z3.is_string(other_var) and not z3.is_string(var):
if other_var.as_string() == '':
# we probably dont want to coerce in this specific case as this is merely a non empty check
if z3.is_bool(var):
return var, z3.BoolVal(False)
if z3.is_int(var):
return var, z3.IntVal(0)
else:
infered_types[str(var)] = 'string'
return z3.String(str(var)), other_var
if z3.is_int(other_var) and not z3.is_int(var):
infered_types[str(var)] = 'number'
return z3.Int(str(var)), other_var
elif var.decl().kind() == z3.Z3_OP_UNINTERPRETED:
if z3.is_bool(var):
infered_types[str(var)] = 'boolean'
if z3.is_string(var):
infered_types[str(var)] = 'string'
if z3.is_int(var):
infered_types[str(var)] = 'number'
else:
# this means that it is non-interpreted and we need to coerce other var to the type of var
if z3.is_string(var) and z3.is_int_value(other_var):
other_var = z3.StringVal(str(other_var))
if z3.is_arith(var) and z3.is_string(other_var):
other_var = z3.IntVal(int(other_var.as_string()))
return var, other_var
def check_value(self, val):
assert val is not None, f"Setting a port's value to None is not allowed"
# check that we only assign correct values to the ports
if isinstance(self.domain, list):
return val in self.domain
elif self.domain is Types.INTEGER:
return isinstance(val, int) or z3.is_int_value(val) or z3.is_int(val)
elif self.domain is Types.REAL: # z3 types
return (isinstance(val, numbers.Number) and not isinstance(val, bool)) or z3.is_real(val)
elif self.domain is Types.INT: # TODO: check also for these types
return isinstance(val, int)
elif self.domain is Types.FLOAT: # TODO: check also for these types
return (isinstance(val, numbers.Number) and not isinstance(val, bool))
elif self.domain is Types.STRING: # TODO: check also for these types
return isinstance(val, str)
elif self.domain is Types.BOOL: # TODO: check also for these types
return isinstance(val, bool)
else:
return False
def unique_leaves(exp, leaf_keys=None):
def insert_and_yield(e):
k = exp_key(e)
if k not in leaf_keys:
leaf_keys.append(k)
yield e
if leaf_keys is None: leaf_keys = []
if z3.is_const(exp) and not (z3.is_int_value(exp)
or z3.is_rational_value(exp)):
for leaf in insert_and_yield(exp):
yield leaf
elif z3.is_app(exp):
for i in range(exp.num_args()):
for leaf in unique_leaves(exp.arg(i), leaf_keys):
yield leaf
else:
assert z3.is_var(exp)
for leaf in insert_and_yield(exp):
yield leaf
def z3_to_val(z3_expr):
"""Send a z3 expression to it's value
as a python expression, if it has one,
otherwise return the expresson itself.
Arguments:
- `z3_expr`: a z3 AST
"""
if z3.is_int_value(z3_expr):
return z3_expr.as_long()
if z3.is_rational_value(z3_expr):
return Fraction(z3_expr.numerator_as_long(), \
z3_expr.denominator_as_long())
elif z3.is_true(z3_expr):
return True
elif z3.is_false(z3_expr):
return False
elif isinstance(z3_expr, z3.FuncInterp):
return z3_to_fun(z3_expr)
else:
return z3_expr
def z3_to_val(z3_expr):
"""Send a z3 expression to its value
as a python expression, if it has one,
otherwise return the expresson itself.
Arguments:
- `z3_expr`: a z3 AST
"""
if z3.is_int_value(z3_expr):
return z3_expr.as_long()
if z3.is_rational_value(z3_expr):
return Fraction(z3_expr.numerator_as_long(), \
z3_expr.denominator_as_long())
elif z3.is_true(z3_expr):
return True
elif z3.is_false(z3_expr):
return False
elif isinstance(z3_expr, z3.FuncInterp):
return z3_to_fun(z3_expr)
else:
return z3_expr
def pp_app(self, a, d, xs):
if z3.is_int_value(a):
return self.pp_int(a)
elif z3.is_rational_value(a):
rat = self.pp_rational(a)
return rat
elif z3.is_algebraic_value(a):
return self.pp_algebraic(a)
elif z3.is_bv_value(a):
return self.pp_bv(a)
elif z3.is_const(a):
return self.pp_const(a)
else:
f = a.decl()
k = f.kind()
if k == Z3_OP_POWER:
return self.pp_power(a, d, xs)
elif k == Z3_OP_DISTINCT:
return self.pp_distinct(a, d, xs)
elif k == Z3_OP_SELECT:
return self.pp_select(a, d, xs)
elif k == Z3_OP_SIGN_EXT or k == Z3_OP_ZERO_EXT or k == Z3_OP_REPEAT:
return self.pp_unary_param(a, d, xs)
elif k == Z3_OP_EXTRACT:
return self.pp_extract(a, d, xs)
elif k == Z3_OP_ARRAY_MAP:
return self.pp_map(a, d, xs)
elif k == Z3_OP_CONST_ARRAY:
return self.pp_K(a, d, xs)
elif z3.is_pattern(a):
return self.pp_pattern(a, d, xs)
elif self.is_infix(k):
return self.pp_infix(a, d, xs)
elif self.is_unary(k):
return self.pp_unary(a, d, xs)
else:
return self.pp_prefix(a, d, xs)
def _state_id_to_prism_variable_to_value(self, state_id):
"""
Returns a dict from prism variables to z3 values representing the valuation of state_id.
:param state_id:
:return:
"""
state_valuation = self.state_graph.get_state_valuation(state_id)
return {input_variable.get_prism_variable(): z3.is_true(z3_value) for input_variable, z3_value in state_valuation.items() if not (z3.is_int_value(z3_value) or z3.is_rational_value(z3_value))}, {input_variable.get_prism_variable() : z3_value.as_long() for input_variable, z3_value in state_valuation.items() if (z3.is_int_value(z3_value) or z3.is_rational_value(z3_value))}
def _back_single_term(self, expr, args, model=None):
assert z3.is_expr(expr)
if z3.is_quantifier(expr):
raise NotImplementedError(
"Quantified back conversion is currently not supported")
assert not len(args) > 2 or \
(z3.is_and(expr) or z3.is_or(expr) or
z3.is_add(expr) or z3.is_mul(expr) or
(len(args) == 3 and (z3.is_ite(expr) or z3.is_array_store(expr)))),\
"Unexpected n-ary term: %s" % expr
res = None
try:
decl = z3.Z3_get_app_decl(expr.ctx_ref(), expr.as_ast())
kind = z3.Z3_get_decl_kind(expr.ctx.ref(), decl)
# Try to get the back-conversion function for the given Kind
fun = self._back_fun[kind]
return fun(args, expr)
except KeyError as ex:
pass
if z3.is_const(expr):
# Const or Symbol
if z3.is_rational_value(expr):
n = expr.numerator_as_long()
d = expr.denominator_as_long()
f = Fraction(n, d)
return self.mgr.Real(f)
elif z3.is_int_value(expr):
n = expr.as_long()
return self.mgr.Int(n)
elif z3.is_bv_value(expr):
n = expr.as_long()
w = expr.size()
return self.mgr.BV(n, w)
elif z3.is_as_array(expr):
if model is None:
raise NotImplementedError("As-array expressions cannot be" \
" handled as they are not " \
"self-contained")
else:
interp_decl = z3.get_as_array_func(expr)
interp = model[interp_decl]
default = self.back(interp.else_value(), model=model)
assign = {}
for i in xrange(interp.num_entries()):
e = interp.entry(i)
assert e.num_args() == 1
idx = self.back(e.arg_value(0), model=model)
val = self.back(e.value(), model=model)
assign[idx] = val
arr_type = self._z3_to_type(expr.sort())
return self.mgr.Array(arr_type.index_type, default, assign)
elif z3.is_algebraic_value(expr):
# Algebraic value
return self.mgr._Algebraic(Numeral(expr))
else:
# it must be a symbol
try:
return self.mgr.get_symbol(str(expr))
except UndefinedSymbolError:
import warnings
symb_type = self._z3_to_type(expr.sort())
warnings.warn("Defining new symbol: %s" % str(expr))
return self.mgr.FreshSymbol(symb_type,
template="__z3_%d")
elif z3.is_function(expr):
# This needs to be after we try to convert regular Symbols
fsymbol = self.mgr.get_symbol(expr.decl().name())
return self.mgr.Function(fsymbol, args)
# If we reach this point, we did not manage to translate the expression
raise ConvertExpressionError(message=("Unsupported expression: %s" %
(str(expr))),
expression=expr)
def expression_evaluable(self, name):
expr = self.expression_get(name)
return z3.is_int_value(expr) or z3.is_bv_value(expr)
def _isNum(self, elem):
return z3.is_rational_value(elem) or z3.is_int_value(elem)
def collect_numerals(z3term):
if z3.is_int_value(z3term) or z3.is_bv_value(z3term):
yield z3term
elif z3.is_app_of(z3term, z3.Z3_OP_ITE):
yield collect_numerals(z3term.arg(1))
yield collect_numerals(z3term.arg(2))
def _back_single_term(self, expr, args, model=None):
assert z3.is_expr(expr)
if z3.is_quantifier(expr):
raise NotImplementedError(
"Quantified back conversion is currently not supported")
res = None
if z3.is_and(expr):
res = self.mgr.And(args)
elif z3.is_or(expr):
res = self.mgr.Or(args)
elif z3.is_add(expr):
res = self.mgr.Plus(args)
elif z3.is_div(expr):
res = self.mgr.Div(args[0], args[1])
elif z3.is_eq(expr):
if self._get_type(args[0]).is_bool_type():
res = self.mgr.Iff(args[0], args[1])
else:
res = self.mgr.Equals(args[0], args[1])
elif z3.is_iff(expr):
res = self.mgr.Iff(args[0], args[1])
elif z3.is_xor(expr):
res = self.mgr.Xor(args[0], args[1])
elif z3.is_false(expr):
res = self.mgr.FALSE()
elif z3.is_true(expr):
res = self.mgr.TRUE()
elif z3.is_gt(expr):
res = self.mgr.GT(args[0], args[1])
elif z3.is_ge(expr):
res = self.mgr.GE(args[0], args[1])
elif z3.is_lt(expr):
res = self.mgr.LT(args[0], args[1])
elif z3.is_le(expr):
res = self.mgr.LE(args[0], args[1])
elif z3.is_mul(expr):
res = self.mgr.Times(args[0], args[1])
elif z3.is_uminus(expr):
tp = self._get_type(args[0])
if tp.is_real_type():
minus_one = self.mgr.Real(-1)
else:
assert tp.is_int_type()
minus_one = self.mgr.Int(-1)
res = self.mgr.Times(args[0], minus_one)
elif z3.is_sub(expr):
res = self.mgr.Minus(args[0], args[1])
elif z3.is_not(expr):
res = self.mgr.Not(args[0])
elif z3.is_implies(expr):
res = self.mgr.Implies(args[0], args[1])
elif z3.is_quantifier(expr):
raise NotImplementedError
elif z3.is_const(expr):
if z3.is_rational_value(expr):
n = expr.numerator_as_long()
d = expr.denominator_as_long()
f = Fraction(n, d)
res = self.mgr.Real(f)
elif z3.is_int_value(expr):
n = expr.as_long()
res = self.mgr.Int(n)
elif z3.is_bv_value(expr):
n = expr.as_long()
w = expr.size()
res = self.mgr.BV(n, w)
elif z3.is_as_array(expr):
if model is None:
raise NotImplementedError("As-array expressions cannot be" \
" handled as they are not " \
"self-contained")
else:
interp_decl = z3.get_as_array_func(expr)
interp = model[interp_decl]
default = self.back(interp.else_value(), model=model)
assign = {}
for i in xrange(interp.num_entries()):
e = interp.entry(i)
assert e.num_args() == 1
idx = self.back(e.arg_value(0), model=model)
val = self.back(e.value(), model=model)
assign[idx] = val
arr_type = self._z3_to_type(expr.sort())
res = self.mgr.Array(arr_type.index_type, default, assign)
elif z3.is_algebraic_value(expr):
# Algebraic value
return self.mgr._Algebraic(Numeral(expr))
else:
# it must be a symbol
res = self.mgr.get_symbol(str(expr))
elif z3.is_ite(expr):
res = self.mgr.Ite(args[0], args[1], args[2])
elif z3.is_function(expr):
res = self.mgr.Function(self.mgr.get_symbol(expr.decl().name()), args)
elif z3.is_to_real(expr):
res = self.mgr.ToReal(args[0])
elif z3.is_bv_and(expr):
res = self.mgr.BVAnd(args[0], args[1])
elif z3.is_bv_or(expr):
res = self.mgr.BVOr(args[0], args[1])
elif z3.is_bv_xor(expr):
res = self.mgr.BVXor(args[0], args[1])
elif z3.is_bv_not(expr):
res = self.mgr.BVNot(args[0])
elif z3.is_bv_neg(expr):
res = self.mgr.BVNeg(args[0])
elif z3.is_bv_concat(expr):
res = self.mgr.BVConcat(args[0], args[1])
elif z3.is_bv_ult(expr):
res = self.mgr.BVULT(args[0], args[1])
elif z3.is_bv_uleq(expr):
res = self.mgr.BVULE(args[0], args[1])
elif z3.is_bv_slt(expr):
res = self.mgr.BVSLT(args[0], args[1])
elif z3.is_bv_sleq(expr):
res = self.mgr.BVSLE(args[0], args[1])
elif z3.is_bv_ugt(expr):
res = self.mgr.BVUGT(args[0], args[1])
elif z3.is_bv_ugeq(expr):
res = self.mgr.BVUGE(args[0], args[1])
elif z3.is_bv_sgt(expr):
res = self.mgr.BVSGT(args[0], args[1])
elif z3.is_bv_sgeq(expr):
res = self.mgr.BVSGE(args[0], args[1])
elif z3.is_bv_extract(expr):
end = z3.get_payload(expr, 0)
start = z3.get_payload(expr, 1)
res = self.mgr.BVExtract(args[0], start, end)
elif z3.is_bv_add(expr):
res = self.mgr.BVAdd(args[0], args[1])
elif z3.is_bv_mul(expr):
res = self.mgr.BVMul(args[0], args[1])
elif z3.is_bv_udiv(expr):
res = self.mgr.BVUDiv(args[0], args[1])
elif z3.is_bv_sdiv(expr):
res = self.mgr.BVSDiv(args[0], args[1])
elif z3.is_bv_urem(expr):
res = self.mgr.BVURem(args[0], args[1])
elif z3.is_bv_srem(expr):
res = self.mgr.BVSRem(args[0], args[1])
elif z3.is_bv_lshl(expr):
res = self.mgr.BVLShl(args[0], args[1])
elif z3.is_bv_lshr(expr):
res = self.mgr.BVLShr(args[0], args[1])
elif z3.is_bv_ashr(expr):
res = self.mgr.BVAShr(args[0], args[1])
elif z3.is_bv_sub(expr):
res = self.mgr.BVSub(args[0], args[1])
elif z3.is_bv_rol(expr):
amount = z3.get_payload(expr, 0)
res = self.mgr.BVRol(args[0], amount)
elif z3.is_bv_ror(expr):
amount = z3.get_payload(expr, 0)
res = self.mgr.BVRor(args[0], amount)
elif z3.is_bv_ext_rol(expr):
amount = args[1].bv_unsigned_value()
res = self.mgr.BVRol(args[0], amount)
elif z3.is_bv_ext_ror(expr):
amount = args[1].bv_unsigned_value()
res = self.mgr.BVRor(args[0], amount)
elif z3.is_bv_sext(expr):
amount = z3.get_payload(expr, 0)
res = self.mgr.BVSExt(args[0], amount)
elif z3.is_bv_zext(expr):
amount = z3.get_payload(expr, 0)
res = self.mgr.BVZExt(args[0], amount)
elif z3.is_array_select(expr):
res = self.mgr.Select(args[0], args[1])
elif z3.is_array_store(expr):
res = self.mgr.Store(args[0], args[1], args[2])
elif z3.is_const_array(expr):
arr_ty = self._z3_to_type(expr.sort())
k = args[0]
res = self.mgr.Array(arr_ty.index_type, k)
elif z3.is_power(expr):
res = self.mgr.Pow(args[0], args[1])
if res is None:
raise ConvertExpressionError(message=("Unsupported expression: %s" %
str(expr)),
expression=expr)
return res
def back(self, expr):
assert z3.is_expr(expr)
if askey(expr) in self.backconversion:
return self.backconversion[askey(expr)]
if z3.is_quantifier(expr):
raise NotImplementedError(
"Quantified back conversion is currently not supported")
args = [self.back(x) for x in expr.children()]
res = None
if z3.is_and(expr):
res = self.mgr.And(args)
elif z3.is_or(expr):
res = self.mgr.Or(args)
elif z3.is_add(expr):
res = self.mgr.Plus(args)
elif z3.is_div(expr):
res = self.mgr.Div(args[0], args[1])
elif z3.is_eq(expr):
if self._get_type(args[0]) == types.BOOL:
res = self.mgr.Iff(args[0], args[1])
else:
res = self.mgr.Equals(args[0], args[1])
elif z3.is_false(expr):
res = self.mgr.FALSE()
elif z3.is_true(expr):
res = self.mgr.TRUE()
elif z3.is_gt(expr):
res = self.mgr.GT(args[0], args[1])
elif z3.is_ge(expr):
res = self.mgr.GE(args[0], args[1])
elif z3.is_lt(expr):
res = self.mgr.LT(args[0], args[1])
elif z3.is_le(expr):
res = self.mgr.LE(args[0], args[1])
elif z3.is_mul(expr):
res = self.mgr.Times(args[0], args[1])
elif z3.is_sub(expr):
res = self.mgr.Minus(args[0], args[1])
elif z3.is_not(expr):
res = self.mgr.Not(args[0])
elif z3.is_quantifier(expr):
if expr.is_forall():
pass
else:
pass
raise NotImplementedError
elif z3.is_const(expr):
if z3.is_rational_value(expr):
n = expr.numerator_as_long()
d = expr.denominator_as_long()
f = Fraction(n, d)
res = self.mgr.Real(f)
elif z3.is_int_value(expr):
n = expr.as_long()
res = self.mgr.Int(n)
else:
# it must be a symbol
res = self.mgr.get_symbol(str(expr))
elif z3.is_ite(expr):
res = self.mgr.Ite(args[0], args[1], args[2])
else:
raise TypeError("Unsupported expression:", expr)
if res is None:
raise TypeError("Unsupported expression:", expr)
self.backconversion[askey(expr)] = res
return res
def _back_single_term(self, expr, args):
assert z3.is_expr(expr)
if z3.is_quantifier(expr):
raise NotImplementedError(
"Quantified back conversion is currently not supported")
res = None
if z3.is_and(expr):
res = self.mgr.And(args)
elif z3.is_or(expr):
res = self.mgr.Or(args)
elif z3.is_add(expr):
res = self.mgr.Plus(args)
elif z3.is_div(expr):
res = self.mgr.Div(args[0], args[1])
elif z3.is_eq(expr):
if self._get_type(args[0]).is_bool_type():
res = self.mgr.Iff(args[0], args[1])
else:
res = self.mgr.Equals(args[0], args[1])
elif z3.is_iff(expr):
res = self.mgr.Iff(args[0], args[1])
elif z3.is_xor(expr):
res = self.mgr.Xor(args[0], args[1])
elif z3.is_false(expr):
res = self.mgr.FALSE()
elif z3.is_true(expr):
res = self.mgr.TRUE()
elif z3.is_gt(expr):
res = self.mgr.GT(args[0], args[1])
elif z3.is_ge(expr):
res = self.mgr.GE(args[0], args[1])
elif z3.is_lt(expr):
res = self.mgr.LT(args[0], args[1])
elif z3.is_le(expr):
res = self.mgr.LE(args[0], args[1])
elif z3.is_mul(expr):
res = self.mgr.Times(args[0], args[1])
elif z3.is_uminus(expr):
tp = self._get_type(args[0])
if tp.is_real_type():
minus_one = self.mgr.Real(-1)
else:
assert tp.is_int_type()
minus_one = self.mgr.Int(-1)
res = self.mgr.Times(args[0], minus_one)
elif z3.is_sub(expr):
res = self.mgr.Minus(args[0], args[1])
elif z3.is_not(expr):
res = self.mgr.Not(args[0])
elif z3.is_implies(expr):
res = self.mgr.Implies(args[0], args[1])
elif z3.is_quantifier(expr):
raise NotImplementedError
elif z3.is_const(expr):
if z3.is_rational_value(expr):
n = expr.numerator_as_long()
d = expr.denominator_as_long()
f = Fraction(n, d)
res = self.mgr.Real(f)
elif z3.is_int_value(expr):
n = expr.as_long()
res = self.mgr.Int(n)
elif z3.is_bv_value(expr):
n = expr.as_long()
w = expr.size()
res = self.mgr.BV(n, w)
else:
# it must be a symbol
res = self.mgr.get_symbol(str(expr))
elif z3.is_ite(expr):
res = self.mgr.Ite(args[0], args[1], args[2])
elif z3.is_function(expr):
res = self.mgr.Function(self.mgr.get_symbol(expr.decl().name()), args)
elif z3.is_to_real(expr):
res = self.mgr.ToReal(args[0])
elif z3.is_bv_and(expr):
res = self.mgr.BVAnd(args[0], args[1])
elif z3.is_bv_or(expr):
res = self.mgr.BVOr(args[0], args[1])
elif z3.is_bv_xor(expr):
res = self.mgr.BVXor(args[0], args[1])
elif z3.is_bv_not(expr):
res = self.mgr.BVNot(args[0])
elif z3.is_bv_neg(expr):
res = self.mgr.BVNeg(args[0])
elif z3.is_bv_concat(expr):
res = self.mgr.BVConcat(args[0], args[1])
elif z3.is_bv_ult(expr):
res = self.mgr.BVULT(args[0], args[1])
elif z3.is_bv_uleq(expr):
res = self.mgr.BVULE(args[0], args[1])
elif z3.is_bv_slt(expr):
res = self.mgr.BVSLT(args[0], args[1])
elif z3.is_bv_sleq(expr):
res = self.mgr.BVSLE(args[0], args[1])
elif z3.is_bv_ugt(expr):
res = self.mgr.BVUGT(args[0], args[1])
elif z3.is_bv_ugeq(expr):
res = self.mgr.BVUGE(args[0], args[1])
elif z3.is_bv_sgt(expr):
res = self.mgr.BVSGT(args[0], args[1])
elif z3.is_bv_sgeq(expr):
res = self.mgr.BVSGE(args[0], args[1])
elif z3.is_bv_extract(expr):
end = z3.get_payload(expr, 0)
start = z3.get_payload(expr, 1)
res = self.mgr.BVExtract(args[0], start, end)
elif z3.is_bv_add(expr):
res = self.mgr.BVAdd(args[0], args[1])
elif z3.is_bv_mul(expr):
res = self.mgr.BVMul(args[0], args[1])
elif z3.is_bv_udiv(expr):
res = self.mgr.BVUDiv(args[0], args[1])
elif z3.is_bv_sdiv(expr):
res = self.mgr.BVSDiv(args[0], args[1])
elif z3.is_bv_urem(expr):
res = self.mgr.BVURem(args[0], args[1])
elif z3.is_bv_srem(expr):
res = self.mgr.BVSRem(args[0], args[1])
elif z3.is_bv_lshl(expr):
res = self.mgr.BVLShl(args[0], args[1])
elif z3.is_bv_lshr(expr):
res = self.mgr.BVLShr(args[0], args[1])
elif z3.is_bv_ashr(expr):
res = self.mgr.BVAShr(args[0], args[1])
elif z3.is_bv_sub(expr):
res = self.mgr.BVSub(args[0], args[1])
elif z3.is_bv_rol(expr):
amount = z3.get_payload(expr, 0)
res = self.mgr.BVRol(args[0], amount)
elif z3.is_bv_ror(expr):
amount = z3.get_payload(expr, 0)
res = self.mgr.BVRor(args[0], amount)
elif z3.is_bv_ext_rol(expr):
amount = args[1].bv_unsigned_value()
res = self.mgr.BVRol(args[0], amount)
elif z3.is_bv_ext_ror(expr):
amount = args[1].bv_unsigned_value()
res = self.mgr.BVRor(args[0], amount)
elif z3.is_bv_sext(expr):
amount = z3.get_payload(expr, 0)
res = self.mgr.BVSExt(args[0], amount)
elif z3.is_bv_zext(expr):
amount = z3.get_payload(expr, 0)
res = self.mgr.BVZExt(args[0], amount)
if res is None:
raise ConvertExpressionError(message=("Unsupported expression: %s" %
str(expr)),
expression=expr)
return res
def _eval_int(expr: z3.ExprRef) -> str: # TODO: this should return int
assert z3.is_int(expr), expr
ans = z3model.eval(expr, model_completion=True)
assert z3.is_int_value(ans), (expr, ans)
return str(ans.as_long())
def _back_single_term(self, expr, args, model=None):
assert z3.is_expr(expr)
if z3.is_quantifier(expr):
raise NotImplementedError(
"Quantified back conversion is currently not supported")
assert not len(args) > 2 or \
(z3.is_and(expr) or z3.is_or(expr) or
z3.is_add(expr) or z3.is_mul(expr) or
(len(args) == 3 and (z3.is_ite(expr) or z3.is_array_store(expr)))),\
"Unexpected n-ary term: %s" % expr
res = None
try:
decl = z3.Z3_get_app_decl(expr.ctx_ref(), expr.as_ast())
kind = z3.Z3_get_decl_kind(expr.ctx.ref(), decl)
# Try to get the back-conversion function for the given Kind
fun = self._back_fun[kind]
return fun(args, expr)
except KeyError as ex:
pass
if z3.is_const(expr):
# Const or Symbol
if z3.is_rational_value(expr):
n = expr.numerator_as_long()
d = expr.denominator_as_long()
f = Fraction(n, d)
return self.mgr.Real(f)
elif z3.is_int_value(expr):
n = expr.as_long()
return self.mgr.Int(n)
elif z3.is_bv_value(expr):
n = expr.as_long()
w = expr.size()
return self.mgr.BV(n, w)
elif z3.is_as_array(expr):
if model is None:
raise NotImplementedError("As-array expressions cannot be" \
" handled as they are not " \
"self-contained")
else:
interp_decl = z3.get_as_array_func(expr)
interp = model[interp_decl]
default = self.back(interp.else_value(), model=model)
assign = {}
for i in xrange(interp.num_entries()):
e = interp.entry(i)
assert e.num_args() == 1
idx = self.back(e.arg_value(0), model=model)
val = self.back(e.value(), model=model)
assign[idx] = val
arr_type = self._z3_to_type(expr.sort())
return self.mgr.Array(arr_type.index_type, default, assign)
elif z3.is_algebraic_value(expr):
# Algebraic value
return self.mgr._Algebraic(Numeral(expr))
else:
# it must be a symbol
try:
return self.mgr.get_symbol(str(expr))
except UndefinedSymbolError:
import warnings
symb_type = self._z3_to_type(expr.sort())
warnings.warn("Defining new symbol: %s" % str(expr))
return self.mgr.FreshSymbol(symb_type, template="__z3_%d")
elif z3.is_function(expr):
# This needs to be after we try to convert regular Symbols
fsymbol = self.mgr.get_symbol(expr.decl().name())
return self.mgr.Function(fsymbol, args)
# If we reach this point, we did not manage to translate the expression
raise ConvertExpressionError(message=("Unsupported expression: %s" %
(str(expr))),
expression=expr)
def _old_model_to_trace(z3model: z3.ModelRef,
num_states: int,
allow_undefined: bool = False) -> Trace:
'''
Convert z3 model to Trace with given number of states.
If allow_undefined is True, the resulting trace may leave some symbols undefined.
'''
trace = Trace(num_states)
keys = Z3Translator._get_keys(num_states)
def rename(s: str) -> str:
return s.replace('!val!', '').replace('@uc_', '')
def _eval(expr: z3.ExprRef) -> z3.ExprRef:
ans = z3model.eval(expr, model_completion=True)
assert bool(ans) is True or bool(ans) is False, (expr, ans)
return ans
prog = syntax.the_program
for z3sort in sorted(z3model.sorts(), key=str):
sort = prog.scope.get_sort(str(z3sort))
assert sort is not None
univ = z3model.get_universe(z3sort)
trace.univs[sort] = tuple(sorted(rename(str(x)) for x in univ))
model_decls = z3model.decls()
all_decls = model_decls
for z3decl in sorted(all_decls, key=str):
z3name = str(z3decl)
for i, k in enumerate(keys):
if z3name.startswith(k):
name = z3name[len(k + '_'):]
R = trace.rel_interps[i]
C = trace.const_interps[i]
F = trace.func_interps[i]
break
else:
name = z3name
R = trace.immut_rel_interps
C = trace.immut_const_interps
F = trace.immut_func_interps
decl = prog.scope.get(name)
assert not isinstance(decl, syntax.Sort) and \
not isinstance(decl, syntax.SortInferencePlaceholder)
if decl is not None:
if isinstance(decl, RelationDecl):
if decl.arity:
rl: RelationInterp = {}
domains = [
z3model.get_universe(z3decl.domain(i))
for i in range(z3decl.arity())
]
if not any(x is None for x in domains):
# Note: if any domain is None, we silently drop this symbol.
# It's not entirely clear that this is an ok thing to do.
g = product(*domains)
for row in g:
relation_expr = z3decl(*row)
ans = _eval(relation_expr)
rl[tuple(rename(str(col))
for col in row)] = bool(ans)
assert decl not in R
R[decl] = rl
else:
ans = z3model.eval(z3decl())
assert decl not in R
R[decl] = {(): bool(ans)}
elif isinstance(decl, FunctionDecl):
fl: FunctionInterp = {}
domains = [
z3model.get_universe(z3decl.domain(i))
for i in range(z3decl.arity())
]
if not any(x is None for x in domains):
# Note: if any domain is None, we silently drop this symbol.
# It's not entirely clear that this is an ok thing to do.
g = product(*domains)
for row in g:
ans = z3model.eval(z3decl(*row))
if z3.is_int_value(ans):
ans_str = str(ans.as_long())
else:
ans_str = rename(ans.decl().name())
fl[tuple(rename(str(col))
for col in row)] = ans_str
assert decl not in F
F[decl] = fl
else:
assert isinstance(decl, ConstantDecl)
v = z3model.eval(z3decl())
if z3.is_int_value(v) or isinstance(v, CVC4Int):
v_str = str(v.as_long())
else:
v_str = rename(v.decl().name())
assert decl not in C
C[decl] = v_str
else:
if name.startswith(TRANSITION_INDICATOR +
'_') and z3model.eval(z3decl()):
name = name[len(TRANSITION_INDICATOR + '_'):]
istr, name = name.split('_', maxsplit=1)
i = int(istr)
if i < len(trace.transitions):
trace.transitions[i] = name
else:
# TODO: not sure what's going on here with check_bmc and pd.check_k_state_implication
# assert False
pass
if allow_undefined:
return trace
def get_univ(d: SortDecl) -> Tuple[Element, ...]:
if d not in trace.univs:
trace.univs[d] = (d.name + '0', )
return trace.univs[d]
def arbitrary_interp_r(r: RelationDecl) -> RelationInterp:
doms = [get_univ(syntax.get_decl_from_sort(s)) for s in r.arity]
return dict.fromkeys(product(*doms), False)
def ensure_defined_r(r: RelationDecl) -> None:
arb_interp: Optional[RelationInterp] = None
for m in (trace.rel_interps
if r.mutable else [trace.immut_rel_interps]):
if r not in m:
if arb_interp is None:
arb_interp = arbitrary_interp_r(r)
m[r] = arb_interp
def arbitrary_interp_c(c: ConstantDecl) -> Element:
if isinstance(c.sort, syntax._BoolSort):
return 'false'
elif isinstance(c.sort, syntax._IntSort):
return '0'
assert isinstance(c.sort, syntax.UninterpretedSort)
sort = c.sort
return get_univ(syntax.get_decl_from_sort(sort))[0]
def ensure_defined_c(c: ConstantDecl) -> None:
arb_interp = arbitrary_interp_c(c)
for m in (trace.const_interps
if c.mutable else [trace.immut_const_interps]):
if c not in m:
m[c] = arb_interp
def arbitrary_interp_f(f: FunctionDecl) -> FunctionInterp:
doms = [get_univ(syntax.get_decl_from_sort(s)) for s in f.arity]
image = get_univ(syntax.get_decl_from_sort(f.sort))[0]
return dict.fromkeys(product(*doms), image)
def ensure_defined_f(f: FunctionDecl) -> None:
arb_interp: Optional[FunctionInterp] = None
for m in (trace.func_interps
if f.mutable else [trace.immut_func_interps]):
if f not in m:
if arb_interp is None:
arb_interp = arbitrary_interp_f(f)
m[f] = arb_interp
for decl in prog.relations_constants_and_functions():
if isinstance(decl, RelationDecl):
ensure_defined_r(decl)
elif isinstance(decl, ConstantDecl):
ensure_defined_c(decl)
elif isinstance(decl, FunctionDecl):
ensure_defined_f(decl)
else:
assert False, decl
return trace
def z3_expr_to_boogie(expr: z3.ExprRef) -> AstExpr:
d = expr.decl()
if (d.arity() == 0):
# Literals and Identifiers
if (isinstance(expr, z3.BoolRef)):
if (z3.is_true(expr)): # No need for explicit ctx
return AstTrue()
elif (z3.is_false(expr)): # No need for explicit ctx
return AstFalse()
else:
return AstId(d.name())
else:
assert isinstance(expr.sort(), z3.ArithSortRef), \
"For now only handle bools and ints"
if (z3.is_int_value(expr)): # No need for explicit ctx
return AstNumber(int(str(expr)))
else:
return AstId(d.name())
elif (d.arity() == 1):
# Unary operators
arg = z3_expr_to_boogie(cast(z3.ExprRef, expr.children()[0]))
boogie_op = {
'-': '-',
'not': '!',
}[d.name()]
return AstUnExpr(boogie_op, arg)
elif (d.name() == "if" and d.arity() == 2):
c = cast(List[z3.ExprRef], expr.children())
cond = z3_expr_to_boogie(c[0])
thenB = z3_expr_to_boogie(c[1])
return AstBinExpr(cond, "==>", thenB)
elif (d.arity() == 2):
# Binary operators
try:
boogie_op, assoc = {
"+": ("+", "left"),
"-": ("-", "left"),
"*": ("*", "left"),
"div": ("div", "left"),
"mod": ("mod", "none"),
"=": ("==", "none"),
"distinct": ("!=", "none"),
"<": ("<", "none"),
">": (">", "none"),
"<=": ("<=", "none"),
">=": (">=", "none"),
"and": ("&&", "left"),
"or": ("||", "left"),
"=>": ("==>", "none"),
"Implies": ("==>", "none"),
}[d.name()]
except:
boogie_op, assoc = d.name(), "func"
c = cast(List[z3.ExprRef], expr.children())
if assoc == "func":
try:
pars = list(map(z3_expr_to_boogie, c))
fun = AstFuncExpr(boogie_op, pars)
except Exception as ex:
error(str(ex))
return fun
elif (assoc == "left"):
return reduce(
lambda acc, x: AstBinExpr(acc, boogie_op, z3_expr_to_boogie(x)
), c[1:], z3_expr_to_boogie(c[0]))
elif (assoc == "none" or assoc == "right"):
assert len(c) == 2, "NYI otherwise"
lhs = z3_expr_to_boogie(c[0])
rhs = z3_expr_to_boogie(c[1])
return AstBinExpr(lhs, boogie_op, rhs)
else:
raise Exception("NYI")
elif (d.name() == "if"):
c = cast(List[z3.ExprRef], expr.children())
cond = z3_expr_to_boogie(c[0])
thenB = z3_expr_to_boogie(c[1])
elseB = z3_expr_to_boogie(c[2])
return AstBinExpr(AstBinExpr(cond, "==>", thenB), "&&",
AstBinExpr(AstUnExpr("!", cond), "==>", elseB))
else:
raise Exception("Can't translate z3 expression " + str(expr) +
" to boogie.")