def test_lira(self): varA = Symbol("A", REAL) varB = Symbol("B", INT) with self.assertRaises(PysmtTypeError): f = And(LT(varA, Plus(varA, Real(1))), GT(varA, Minus(varB, Int(1)))) f = And(LT(varA, Plus(varA, Real(1))), GT(varA, ToReal(Minus(varB, Int(1))))) g = Equals(varA, ToReal(varB)) self.assertUnsat(And(f, g, Equals(varA, Real(1.2))), "Formula was expected to be unsat", logic=QF_UFLIRA)
def test_toreal(self): p = Symbol("p", INT) rp = ToReal(p) self.assertEqual(rp.to_smtlib(daggify=False), "(to_real p)") self.assertEqual(rp.to_smtlib(daggify=True), "(let ((.def_0 (to_real p))) .def_0)")
def test_dependencies_not_includes_toreal(self): p = Symbol("p", INT) r = ToReal(p) deps = r.get_free_variables() self.assertIn(p, deps) self.assertNotIn(r, deps)
def test_qe_z3(self): qe = QuantifierEliminator(name='z3') self._bool_example(qe) self._real_example(qe) self._int_example(qe) self._alternation_bool_example(qe) self._alternation_real_example(qe) self._alternation_int_example(qe) self._std_examples(qe, LRA) self._std_examples(qe, LIA) # Additional test for raising error on back conversion of # quantified formulae p, q = Symbol("p", INT), Symbol("q", INT) f = ForAll([p], Exists([q], Equals(ToReal(p), Plus(ToReal(q), ToReal(Int(1)))))) with self.assertRaises(NotImplementedError): qe.eliminate_quantifiers(f).simplify()
def get_full_example_formulae(environment=None): """Return a list of Examples using the given environment.""" if environment is None: environment = get_env() with environment: x = Symbol("x", BOOL) y = Symbol("y", BOOL) p = Symbol("p", INT) q = Symbol("q", INT) r = Symbol("r", REAL) s = Symbol("s", REAL) aii = Symbol("aii", ARRAY_INT_INT) ari = Symbol("ari", ArrayType(REAL, INT)) arb = Symbol("arb", ArrayType(REAL, BV8)) abb = Symbol("abb", ArrayType(BV8, BV8)) nested_a = Symbol("a_arb_aii", ArrayType(ArrayType(REAL, BV8), ARRAY_INT_INT)) rf = Symbol("rf", FunctionType(REAL, [REAL, REAL])) rg = Symbol("rg", FunctionType(REAL, [REAL])) ih = Symbol("ih", FunctionType(INT, [REAL, INT])) ig = Symbol("ig", FunctionType(INT, [INT])) bf = Symbol("bf", FunctionType(BOOL, [BOOL])) bg = Symbol("bg", FunctionType(BOOL, [BOOL])) bv8 = Symbol("bv1", BV8) bv16 = Symbol("bv2", BV16) result = [ # Formula, is_valid, is_sat, is_qf Example(hr="(x & y)", expr=And(x, y), is_valid=False, is_sat=True, logic=pysmt.logics.QF_BOOL), Example(hr="(x <-> y)", expr=Iff(x, y), is_valid=False, is_sat=True, logic=pysmt.logics.QF_BOOL), Example(hr="((x | y) & (! (x | y)))", expr=And(Or(x, y), Not(Or(x, y))), is_valid=False, is_sat=False, logic=pysmt.logics.QF_BOOL), Example(hr="(x & (! y))", expr=And(x, Not(y)), is_valid=False, is_sat=True, logic=pysmt.logics.QF_BOOL), Example(hr="(False -> True)", expr=Implies(FALSE(), TRUE()), is_valid=True, is_sat=True, logic=pysmt.logics.QF_BOOL), # # LIA # Example(hr="((q < p) & (x -> y))", expr=And(GT(p, q), Implies(x, y)), is_valid=False, is_sat=True, logic=pysmt.logics.QF_IDL), Example(hr="(((p + q) = 5) & (q < p))", expr=And(Equals(Plus(p, q), Int(5)), GT(p, q)), is_valid=False, is_sat=True, logic=pysmt.logics.QF_LIA), Example(hr="((q <= p) | (p <= q))", expr=Or(GE(p, q), LE(p, q)), is_valid=True, is_sat=True, logic=pysmt.logics.QF_IDL), Example(hr="(! (p < (q * 2)))", expr=Not(LT(p, Times(q, Int(2)))), is_valid=False, is_sat=True, logic=pysmt.logics.QF_LIA), Example(hr="(p < (p - (5 - 2)))", expr=GT(Minus(p, Minus(Int(5), Int(2))), p), is_valid=False, is_sat=False, logic=pysmt.logics.QF_IDL), Example(hr="((x ? 7 : ((p + -1) * 3)) = q)", expr=Equals( Ite(x, Int(7), Times(Plus(p, Int(-1)), Int(3))), q), is_valid=False, is_sat=True, logic=pysmt.logics.QF_LIA), Example(hr="(p < (q + 1))", expr=LT(p, Plus(q, Int(1))), is_valid=False, is_sat=True, logic=pysmt.logics.QF_LIA), # # LRA # Example(hr="((s < r) & (x -> y))", expr=And(GT(r, s), Implies(x, y)), is_valid=False, is_sat=True, logic=pysmt.logics.QF_RDL), Example(hr="(((r + s) = 28/5) & (s < r))", expr=And(Equals(Plus(r, s), Real(Fraction("5.6"))), GT(r, s)), is_valid=False, is_sat=True, logic=pysmt.logics.QF_LRA), Example(hr="((s <= r) | (r <= s))", expr=Or(GE(r, s), LE(r, s)), is_valid=True, is_sat=True, logic=pysmt.logics.QF_RDL), Example(hr="(! ((r * 2.0) < (s * 2.0)))", expr=Not(LT(Div(r, Real((1, 2))), Times(s, Real(2)))), is_valid=False, is_sat=True, logic=pysmt.logics.QF_LRA), Example(hr="(! (r < (r - (5.0 - 2.0))))", expr=Not(GT(Minus(r, Minus(Real(5), Real(2))), r)), is_valid=True, is_sat=True, logic=pysmt.logics.QF_RDL), Example(hr="((x ? 7.0 : ((s + -1.0) * 3.0)) = r)", expr=Equals( Ite(x, Real(7), Times(Plus(s, Real(-1)), Real(3))), r), is_valid=False, is_sat=True, logic=pysmt.logics.QF_LRA), # # EUF # Example(hr="(bf(x) <-> bg(x))", expr=Iff(Function(bf, (x, )), Function(bg, (x, ))), is_valid=False, is_sat=True, logic=pysmt.logics.QF_UF), Example(hr="(rf(5.0, rg(r)) = 0.0)", expr=Equals(Function(rf, (Real(5), Function(rg, (r, )))), Real(0)), is_valid=False, is_sat=True, logic=pysmt.logics.QF_UFLRA), Example(hr="((rg(r) = (5.0 + 2.0)) <-> (rg(r) = 7.0))", expr=Iff(Equals(Function(rg, [r]), Plus(Real(5), Real(2))), Equals(Function(rg, [r]), Real(7))), is_valid=True, is_sat=True, logic=pysmt.logics.QF_UFLRA), Example( hr="((r = (s + 1.0)) & (rg(s) = 5.0) & (rg((r - 1.0)) = 7.0))", expr=And([ Equals(r, Plus(s, Real(1))), Equals(Function(rg, [s]), Real(5)), Equals(Function(rg, [Minus(r, Real(1))]), Real(7)) ]), is_valid=False, is_sat=False, logic=pysmt.logics.QF_UFLRA), # # BV # Example(hr="((1_32 & 0_32) = 0_32)", expr=Equals(BVAnd(BVOne(32), BVZero(32)), BVZero(32)), is_valid=True, is_sat=True, logic=pysmt.logics.QF_BV), Example(hr="((! 2_3) = 5_3)", expr=Equals(BVNot(BV("010")), BV("101")), is_valid=True, is_sat=True, logic=pysmt.logics.QF_BV), Example(hr="((7_3 xor 0_3) = 0_3)", expr=Equals(BVXor(BV("111"), BV("000")), BV("000")), is_valid=False, is_sat=False, logic=pysmt.logics.QF_BV), Example(hr="((bv1::bv1) u< 0_16)", expr=BVULT(BVConcat(bv8, bv8), BVZero(16)), is_valid=False, is_sat=False, logic=pysmt.logics.QF_BV), Example(hr="(1_32[0:7] = 1_8)", expr=Equals(BVExtract(BVOne(32), end=7), BVOne(8)), is_valid=True, is_sat=True, logic=pysmt.logics.QF_BV), Example(hr="(0_8 u< (((bv1 + 1_8) * 5_8) u/ 5_8))", expr=BVUGT( BVUDiv(BVMul(BVAdd(bv8, BVOne(8)), BV(5, width=8)), BV(5, width=8)), BVZero(8)), is_valid=False, is_sat=True, logic=pysmt.logics.QF_BV), Example(hr="(0_16 u<= bv2)", expr=BVUGE(bv16, BVZero(16)), is_valid=True, is_sat=True, logic=pysmt.logics.QF_BV), Example(hr="(0_16 s<= bv2)", expr=BVSGE(bv16, BVZero(16)), is_valid=False, is_sat=True, logic=pysmt.logics.QF_BV), Example( hr="((0_32 u< (5_32 u% 2_32)) & ((5_32 u% 2_32) u<= 1_32))", expr=And( BVUGT(BVURem(BV(5, width=32), BV(2, width=32)), BVZero(32)), BVULE(BVURem(BV(5, width=32), BV(2, width=32)), BVOne(32))), is_valid=True, is_sat=True, logic=pysmt.logics.QF_BV), Example(hr="((((1_32 + (- 1_32)) << 1_32) >> 1_32) = 1_32)", expr=Equals( BVLShr(BVLShl(BVAdd(BVOne(32), BVNeg(BVOne(32))), 1), 1), BVOne(32)), is_valid=False, is_sat=False, logic=pysmt.logics.QF_BV), Example(hr="((1_32 - 1_32) = 0_32)", expr=Equals(BVSub(BVOne(32), BVOne(32)), BVZero(32)), is_valid=True, is_sat=True, logic=pysmt.logics.QF_BV), # Rotations Example(hr="(((1_32 ROL 1) ROR 1) = 1_32)", expr=Equals(BVRor(BVRol(BVOne(32), 1), 1), BVOne(32)), is_valid=True, is_sat=True, logic=pysmt.logics.QF_BV), # Extensions Example(hr="((0_5 ZEXT 11) = (0_1 SEXT 15))", expr=Equals(BVZExt(BVZero(5), 11), BVSExt(BVZero(1), 15)), is_valid=True, is_sat=True, logic=pysmt.logics.QF_BV), Example(hr="((bv2 - bv2) = 0_16)", expr=Equals(BVSub(bv16, bv16), BVZero(16)), is_valid=True, is_sat=True, logic=pysmt.logics.QF_BV), Example(hr="((bv2 - bv2)[0:7] = bv1)", expr=Equals(BVExtract(BVSub(bv16, bv16), 0, 7), bv8), is_valid=False, is_sat=True, logic=pysmt.logics.QF_BV), Example(hr="((bv2[0:7] bvcomp bv1) = 1_1)", expr=Equals(BVComp(BVExtract(bv16, 0, 7), bv8), BVOne(1)), is_valid=False, is_sat=True, logic=pysmt.logics.QF_BV), Example(hr="((bv2 bvcomp bv2) = 0_1)", expr=Equals(BVComp(bv16, bv16), BVZero(1)), is_valid=False, is_sat=False, logic=pysmt.logics.QF_BV), Example(hr="(bv2 s< bv2)", expr=BVSLT(bv16, bv16), is_valid=False, is_sat=False, logic=pysmt.logics.QF_BV), Example(hr="(bv2 s< 0_16)", expr=BVSLT(bv16, BVZero(16)), is_valid=False, is_sat=True, logic=pysmt.logics.QF_BV), Example(hr="((bv2 s< 0_16) | (0_16 s<= bv2))", expr=Or(BVSGT(BVZero(16), bv16), BVSGE(bv16, BVZero(16))), is_valid=True, is_sat=True, logic=pysmt.logics.QF_BV), Example(hr="(bv2 u< bv2)", expr=BVULT(bv16, bv16), is_valid=False, is_sat=False, logic=pysmt.logics.QF_BV), Example(hr="(bv2 u< 0_16)", expr=BVULT(bv16, BVZero(16)), is_valid=False, is_sat=False, logic=pysmt.logics.QF_BV), Example(hr="((bv2 | 0_16) = bv2)", expr=Equals(BVOr(bv16, BVZero(16)), bv16), is_valid=True, is_sat=True, logic=pysmt.logics.QF_BV), Example(hr="((bv2 & 0_16) = 0_16)", expr=Equals(BVAnd(bv16, BVZero(16)), BVZero(16)), is_valid=True, is_sat=True, logic=pysmt.logics.QF_BV), Example(hr="((0_16 s< bv2) & ((bv2 s/ 65535_16) s< 0_16))", expr=And(BVSLT(BVZero(16), bv16), BVSLT(BVSDiv(bv16, SBV(-1, 16)), BVZero(16))), is_valid=False, is_sat=True, logic=pysmt.logics.QF_BV), Example(hr="((0_16 s< bv2) & ((bv2 s% 1_16) s< 0_16))", expr=And(BVSLT(BVZero(16), bv16), BVSLT(BVSRem(bv16, BVOne(16)), BVZero(16))), is_valid=False, is_sat=False, logic=pysmt.logics.QF_BV), Example(hr="((bv2 u% 1_16) = 0_16)", expr=Equals(BVURem(bv16, BVOne(16)), BVZero(16)), is_valid=True, is_sat=True, logic=pysmt.logics.QF_BV), Example(hr="((bv2 s% 1_16) = 0_16)", expr=Equals(BVSRem(bv16, BVOne(16)), BVZero(16)), is_valid=True, is_sat=True, logic=pysmt.logics.QF_BV), Example(hr="((bv2 s% (- 1_16)) = 0_16)", expr=Equals(BVSRem(bv16, BVNeg(BVOne(16))), BVZero(16)), is_valid=True, is_sat=True, logic=pysmt.logics.QF_BV), Example(hr="((bv2 a>> 0_16) = bv2)", expr=Equals(BVAShr(bv16, BVZero(16)), bv16), is_valid=True, is_sat=True, logic=pysmt.logics.QF_BV), Example(hr="((0_16 s<= bv2) & ((bv2 a>> 1_16) = (bv2 >> 1_16)))", expr=And( BVSLE(BVZero(16), bv16), Equals(BVAShr(bv16, BVOne(16)), BVLShr(bv16, BVOne(16)))), is_valid=False, is_sat=True, logic=pysmt.logics.QF_BV), # # Quantification # Example(hr="(forall y . (x -> y))", expr=ForAll([y], Implies(x, y)), is_valid=False, is_sat=True, logic=pysmt.logics.BOOL), Example(hr="(forall p, q . ((p + q) = 0))", expr=ForAll([p, q], Equals(Plus(p, q), Int(0))), is_valid=False, is_sat=False, logic=pysmt.logics.LIA), Example( hr="(forall r, s . (((0.0 < r) & (0.0 < s)) -> ((r - s) < r)))", expr=ForAll([r, s], Implies(And(GT(r, Real(0)), GT(s, Real(0))), (LT(Minus(r, s), r)))), is_valid=True, is_sat=True, logic=pysmt.logics.LRA), Example(hr="(exists x, y . (x -> y))", expr=Exists([x, y], Implies(x, y)), is_valid=True, is_sat=True, logic=pysmt.logics.BOOL), Example(hr="(exists p, q . ((p + q) = 0))", expr=Exists([p, q], Equals(Plus(p, q), Int(0))), is_valid=True, is_sat=True, logic=pysmt.logics.LIA), Example(hr="(exists r . (forall s . (r < (r - s))))", expr=Exists([r], ForAll([s], GT(Minus(r, s), r))), is_valid=False, is_sat=False, logic=pysmt.logics.LRA), Example(hr="(forall r . (exists s . (r < (r - s))))", expr=ForAll([r], Exists([s], GT(Minus(r, s), r))), is_valid=True, is_sat=True, logic=pysmt.logics.LRA), Example(hr="(x & (forall r . ((r + s) = 5.0)))", expr=And(x, ForAll([r], Equals(Plus(r, s), Real(5)))), is_valid=False, is_sat=False, logic=pysmt.logics.LRA), Example(hr="(exists x . ((x <-> (5.0 < s)) & (s < 3.0)))", expr=Exists([x], (And(Iff(x, GT(s, Real(5))), LT(s, Real(3))))), is_valid=False, is_sat=True, logic=pysmt.logics.LRA), # # UFLIRA # Example(hr="((p < ih(r, q)) & (x -> y))", expr=And(GT(Function(ih, (r, q)), p), Implies(x, y)), is_valid=False, is_sat=True, logic=pysmt.logics.QF_UFLIRA), Example( hr= "(((p - 3) = q) -> ((p < ih(r, (q + 3))) | (ih(r, p) <= p)))", expr=Implies( Equals(Minus(p, Int(3)), q), Or(GT(Function(ih, (r, Plus(q, Int(3)))), p), LE(Function(ih, (r, p)), p))), is_valid=True, is_sat=True, logic=pysmt.logics.QF_UFLIRA), Example( hr= "(((ToReal((p - 3)) = r) & (ToReal(q) = r)) -> ((p < ih(ToReal((p - 3)), (q + 3))) | (ih(r, p) <= p)))", expr=Implies( And(Equals(ToReal(Minus(p, Int(3))), r), Equals(ToReal(q), r)), Or( GT( Function( ih, (ToReal(Minus(p, Int(3))), Plus(q, Int(3)))), p), LE(Function(ih, (r, p)), p))), is_valid=True, is_sat=True, logic=pysmt.logics.QF_UFLIRA), Example( hr= "(! (((ToReal((p - 3)) = r) & (ToReal(q) = r)) -> ((p < ih(ToReal((p - 3)), (q + 3))) | (ih(r, p) <= p))))", expr=Not( Implies( And(Equals(ToReal(Minus(p, Int(3))), r), Equals(ToReal(q), r)), Or( GT( Function(ih, (ToReal(Minus( p, Int(3))), Plus(q, Int(3)))), p), LE(Function(ih, (r, p)), p)))), is_valid=False, is_sat=False, logic=pysmt.logics.QF_UFLIRA), Example( hr= """("Did you know that any string works? #yolo" & "10" & "|#somesolverskeepthe||" & " ")""", expr=And(Symbol("Did you know that any string works? #yolo"), Symbol("10"), Symbol("|#somesolverskeepthe||"), Symbol(" ")), is_valid=False, is_sat=True, logic=pysmt.logics.QF_BOOL), # # Arrays # Example(hr="((q = 0) -> (aii[0 := 0] = aii[0 := q]))", expr=Implies( Equals(q, Int(0)), Equals(Store(aii, Int(0), Int(0)), Store(aii, Int(0), q))), is_valid=True, is_sat=True, logic=pysmt.logics.QF_ALIA), Example(hr="(aii[0 := 0][0] = 0)", expr=Equals(Select(Store(aii, Int(0), Int(0)), Int(0)), Int(0)), is_valid=True, is_sat=True, logic=pysmt.logics.QF_ALIA), Example(hr="((Array{Int, Int}(0)[1 := 1] = aii) & (aii[1] = 0))", expr=And(Equals(Array(INT, Int(0), {Int(1): Int(1)}), aii), Equals(Select(aii, Int(1)), Int(0))), is_valid=False, is_sat=False, logic=pysmt.logics.get_logic_by_name("QF_ALIA*")), Example(hr="((Array{Int, Int}(0)[1 := 3] = aii) & (aii[1] = 3))", expr=And(Equals(Array(INT, Int(0), {Int(1): Int(3)}), aii), Equals(Select(aii, Int(1)), Int(3))), is_valid=False, is_sat=True, logic=pysmt.logics.get_logic_by_name("QF_ALIA*")), Example(hr="((Array{Real, Int}(10) = ari) & (ari[6/5] = 0))", expr=And(Equals(Array(REAL, Int(10)), ari), Equals(Select(ari, Real((6, 5))), Int(0))), is_valid=False, is_sat=False, logic=pysmt.logics.get_logic_by_name("QF_AUFBVLIRA*")), Example( hr= "((Array{Real, Int}(0)[1.0 := 10][2.0 := 20][3.0 := 30][4.0 := 40] = ari) & (! ((ari[0.0] = 0) & (ari[1.0] = 10) & (ari[2.0] = 20) & (ari[3.0] = 30) & (ari[4.0] = 40))))", expr=And( Equals( Array( REAL, Int(0), { Real(1): Int(10), Real(2): Int(20), Real(3): Int(30), Real(4): Int(40) }), ari), Not( And(Equals(Select(ari, Real(0)), Int(0)), Equals(Select(ari, Real(1)), Int(10)), Equals(Select(ari, Real(2)), Int(20)), Equals(Select(ari, Real(3)), Int(30)), Equals(Select(ari, Real(4)), Int(40))))), is_valid=False, is_sat=False, logic=pysmt.logics.get_logic_by_name("QF_AUFBVLIRA*")), Example( hr= "((Array{Real, Int}(0)[1.0 := 10][2.0 := 20][3.0 := 30][4.0 := 40][5.0 := 50] = ari) & (! ((ari[0.0] = 0) & (ari[1.0] = 10) & (ari[2.0] = 20) & (ari[3.0] = 30) & (ari[4.0] = 40) & (ari[5.0] = 50))))", expr=And( Equals( Array( REAL, Int(0), { Real(1): Int(10), Real(2): Int(20), Real(3): Int(30), Real(4): Int(40), Real(5): Int(50) }), ari), Not( And(Equals(Select(ari, Real(0)), Int(0)), Equals(Select(ari, Real(1)), Int(10)), Equals(Select(ari, Real(2)), Int(20)), Equals(Select(ari, Real(3)), Int(30)), Equals(Select(ari, Real(4)), Int(40)), Equals(Select(ari, Real(5)), Int(50))))), is_valid=False, is_sat=False, logic=pysmt.logics.get_logic_by_name("QF_AUFBVLIRA*")), Example( hr= "((a_arb_aii = Array{Array{Real, BV{8}}, Array{Int, Int}}(Array{Int, Int}(7))) -> (a_arb_aii[arb][42] = 7))", expr=Implies( Equals(nested_a, Array(ArrayType(REAL, BV8), Array(INT, Int(7)))), Equals(Select(Select(nested_a, arb), Int(42)), Int(7))), is_valid=True, is_sat=True, logic=pysmt.logics.get_logic_by_name("QF_AUFBVLIRA*")), Example(hr="(abb[bv1 := y_][bv1 := z_] = abb[bv1 := z_])", expr=Equals( Store(Store(abb, bv8, Symbol("y_", BV8)), bv8, Symbol("z_", BV8)), Store(abb, bv8, Symbol("z_", BV8))), is_valid=True, is_sat=True, logic=pysmt.logics.QF_ABV), Example(hr="((r / s) = (r * s))", expr=Equals(Div(r, s), Times(r, s)), is_valid=False, is_sat=True, logic=pysmt.logics.QF_NRA), Example(hr="(2.0 = (r * r))", expr=Equals(Real(2), Times(r, r)), is_valid=False, is_sat=True, logic=pysmt.logics.QF_NRA), Example(hr="((p ^ 2) = 0)", expr=Equals(Pow(p, Int(2)), Int(0)), is_valid=False, is_sat=True, logic=pysmt.logics.QF_NIA), Example(hr="((r ^ 2.0) = 0.0)", expr=Equals(Pow(r, Real(2)), Real(0)), is_valid=False, is_sat=True, logic=pysmt.logics.QF_NRA), Example(hr="((r * r * r) = 25.0)", expr=Equals(Times(r, r, r), Real(25)), is_valid=False, is_sat=True, logic=pysmt.logics.QF_NRA), Example(hr="((5.0 * r * 5.0) = 25.0)", expr=Equals(Times(Real(5), r, Real(5)), Real(25)), is_valid=False, is_sat=True, logic=pysmt.logics.QF_LRA), Example(hr="((p * p * p) = 25)", expr=Equals(Times(p, p, p), Int(25)), is_valid=False, is_sat=False, logic=pysmt.logics.QF_NIA), Example(hr="((5 * p * 5) = 25)", expr=Equals(Times(Int(5), p, Int(5)), Int(25)), is_valid=False, is_sat=True, logic=pysmt.logics.QF_LIA), Example(hr="(((1 - 1) * p * 1) = 0)", expr=Equals(Times(Minus(Int(1), Int(1)), p, Int(1)), Int(0)), is_valid=True, is_sat=True, logic=pysmt.logics.QF_LIA), # Huge Fractions: Example( hr= "((r * 1606938044258990275541962092341162602522202993782792835301376/7) = -20480000000000000000000000.0)", expr=Equals(Times(r, Real(Fraction(2**200, 7))), Real(-200**11)), is_valid=False, is_sat=True, logic=pysmt.logics.QF_LRA), Example(hr="(((r + 5.0 + s) * (s + 2.0 + r)) = 0.0)", expr=Equals( Times(Plus(r, Real(5), s), Plus(s, Real(2), r)), Real(0)), is_valid=False, is_sat=True, logic=pysmt.logics.QF_NRA), Example( hr= "(((p + 5 + q) * (p - (q - 5))) = ((p * p) + (10 * p) + 25 + (-1 * q * q)))", expr=Equals( Times(Plus(p, Int(5), q), Minus(p, Minus(q, Int(5)))), Plus(Times(p, p), Times(Int(10), p), Int(25), Times(Int(-1), q, q))), is_valid=True, is_sat=True, logic=pysmt.logics.QF_NIA), ] return result
def expr_to_pysmt(context: TranslationContext, expr: Expr, *, is_expectation: bool = False, allow_infinity: bool = False) -> FNode: """ Translate a pGCL expression to a pySMT formula. Note that substitution expressions are not allowed here (they are not supported in pySMT). You can pass in the optional `is_expectation` parameter to have all integer values converted to real values. If `allow_infinity` is `True`, then infinity expressions will be mapped directly to the `infinity` variable of the given :py:class:`TranslationContext`. Take care to appropriately constrain the `infinity` variable! Note that arithmetic expressions may not contain infinity, to prevent expressions like `infinity - infinity`. .. doctest:: >>> from probably.pgcl.parser import parse_expr >>> from pysmt.shortcuts import Symbol >>> from pysmt.typing import INT >>> expr = parse_expr("x + 4 * 13") >>> context = TranslationContext({"x": Symbol("x", INT)}) >>> expr_to_pysmt(context, expr) (x + (4 * 13)) """ if isinstance(expr, BoolLitExpr): return TRUE() if expr.value else FALSE() elif isinstance(expr, NatLitExpr): if is_expectation: return ToReal(Int(expr.value)) else: return Int(expr.value) elif isinstance(expr, FloatLitExpr): if expr.is_infinite(): if not allow_infinity: raise Exception( f"Infinity is not allowed in this expression: {expr}") return context.infinity else: return Real(Fraction(expr.value)) elif isinstance(expr, VarExpr): var = context.variables[expr.var] if is_expectation and get_type(var) == INT: var = ToReal(var) return var elif isinstance(expr, UnopExpr): operand = expr_to_pysmt(context, expr.expr, is_expectation=False, allow_infinity=allow_infinity) if expr.operator == Unop.NEG: return Not(operand) elif expr.operator == Unop.IVERSON: return Ite(operand, Real(1), Real(0)) elif isinstance(expr, BinopExpr): # `is_expectation` is disabled if we enter a non-arithmetic expression # (we do not convert integers to reals within a boolean expression such # as `x == y`, for example). # # Similarly, `allow_infinity` is disabled if we enter an arithmetic # expression because calculations with infinity are hard to make sense of. is_arith_op = expr.operator in [Binop.PLUS, Binop.MINUS, Binop.TIMES] is_expectation = is_expectation # TODO: and is_arith_op allow_infinity = allow_infinity # TODO: and not is_arith_op?!??! lhs = expr_to_pysmt(context, expr.lhs, is_expectation=is_expectation, allow_infinity=allow_infinity) rhs = expr_to_pysmt(context, expr.rhs, is_expectation=is_expectation, allow_infinity=allow_infinity) if expr.operator == Binop.OR: return Or(lhs, rhs) elif expr.operator == Binop.AND: return And(lhs, rhs) elif expr.operator == Binop.LEQ: return LE(lhs, rhs) elif expr.operator == Binop.LE: return LT(lhs, rhs) elif expr.operator == Binop.EQ: return EqualsOrIff(lhs, rhs) elif expr.operator == Binop.PLUS: return Plus(lhs, rhs) elif expr.operator == Binop.MINUS: return Ite(LE(lhs, rhs), (Int(0) if get_type(lhs) == INT else Real(0)), Minus(lhs, rhs)) elif expr.operator == Binop.TIMES: return Times(lhs, rhs) elif isinstance(expr, SubstExpr): raise Exception("Substitution expression is not allowed here.") raise Exception("unreachable")
def test_toreal(self): p = Symbol("p", INT) rp = ToReal(p) rp_string = self.print_to_string(rp) self.assertEqual(rp_string, "(to_real p)")
# We create a map from BitVectors to Reals, so that each bitvector # value (interpreted as unary number) is equal to the Real # value. # # The map is represented by an Array of type BV8 -> Real map_type = ArrayType(BV8, REAL) my_map = Symbol("my_map", map_type) # Fill-up the map, by defining all 256 values: for i in range(0, 255): my_map = my_map.Store(BV(i, 8), Real(i)) # We want to find find a value for which our relation does not work. # In other words, we ask if there is a value for the bitvector # s.t. the corresponding value in the array is different from the # unary interpretation of the bitvector. bv_var = Symbol("bv", BV8) int_var = Symbol("int", INT) real_var = Symbol("real", REAL) f = And( # Convert the BV into INT int_var.Equals(BVToNatural(bv_var)), # Convert the INT into REAL real_var.Equals(ToReal(int_var)), # Compare the value stored in the map with the REAL value my_map.Select(bv_var).NotEquals(real_var) ) print(get_model(f)) # Indeed our range only gets up to 254!!!
def test_substitute_to_real(self): p = Symbol("p", INT) f = LT(ToReal(p), Real(0)) new_f = f.substitute({p: Real(1)}).simplify() self.assertEqual(new_f, Bool(False))
def get_example_formulae(environment=None): if environment is None: environment = get_env() with environment: x = Symbol("x", BOOL) y = Symbol("y", BOOL) p = Symbol("p", INT) q = Symbol("q", INT) r = Symbol("r", REAL) s = Symbol("s", REAL) rf = Symbol("rf", FunctionType(REAL, [REAL, REAL])) rg = Symbol("rg", FunctionType(REAL, [REAL])) ih = Symbol("ih", FunctionType(INT, [REAL, INT])) ig = Symbol("ig", FunctionType(INT, [INT])) bv8 = Symbol("bv1", BV8) bv16 = Symbol("bv2", BV16) result = [ # Formula, is_valid, is_sat, is_qf # x /\ y Example(expr=And(x, y), is_valid=False, is_sat=True, logic=pysmt.logics.QF_BOOL), # x <-> y Example(expr=Iff(x, y), is_valid=False, is_sat=True, logic=pysmt.logics.QF_BOOL), # (x \/ y ) /\ ! ( x \/ y ) Example(expr=And(Or(x, y), Not(Or(x, y))), is_valid=False, is_sat=False, logic=pysmt.logics.QF_BOOL), # (x /\ !y) Example(expr=And(x, Not(y)), is_valid=False, is_sat=True, logic=pysmt.logics.QF_BOOL), # False -> True Example(expr=Implies(FALSE(), TRUE()), is_valid=True, is_sat=True, logic=pysmt.logics.QF_BOOL), # # LIA # # (p > q) /\ x -> y Example(expr=And(GT(p, q), Implies(x, y)), is_valid=False, is_sat=True, logic=pysmt.logics.QF_IDL), # (p + q) = 5 /\ (p > q) Example(expr=And(Equals(Plus(p, q), Int(5)), GT(p, q)), is_valid=False, is_sat=True, logic=pysmt.logics.QF_LIA), # (p >= q) \/ ( p <= q) Example(expr=Or(GE(p, q), LE(p, q)), is_valid=True, is_sat=True, logic=pysmt.logics.QF_IDL), # !( p < q * 2 ) Example(expr=Not(LT(p, Times(q, Int(2)))), is_valid=False, is_sat=True, logic=pysmt.logics.QF_LIA), # p - (5 - 2) > p Example(expr=GT(Minus(p, Minus(Int(5), Int(2))), p), is_valid=False, is_sat=False, logic=pysmt.logics.QF_IDL), # x ? 7: (p + -1) * 3 = q Example(expr=Equals( Ite(x, Int(7), Times(Plus(p, Int(-1)), Int(3))), q), is_valid=False, is_sat=True, logic=pysmt.logics.QF_LIA), Example(expr=LT(p, Plus(q, Int(1))), is_valid=False, is_sat=True, logic=pysmt.logics.QF_LIA), # # LRA # # (r > s) /\ x -> y Example(expr=And(GT(r, s), Implies(x, y)), is_valid=False, is_sat=True, logic=pysmt.logics.QF_RDL), # (r + s) = 5.6 /\ (r > s) Example(expr=And(Equals(Plus(r, s), Real(Fraction("5.6"))), GT(r, s)), is_valid=False, is_sat=True, logic=pysmt.logics.QF_LRA), # (r >= s) \/ ( r <= s) Example(expr=Or(GE(r, s), LE(r, s)), is_valid=True, is_sat=True, logic=pysmt.logics.QF_RDL), # !( (r / (1/2)) < s * 2 ) Example(expr=Not(LT(Div(r, Real((1, 2))), Times(s, Real(2)))), is_valid=False, is_sat=True, logic=pysmt.logics.QF_LRA), # ! ( r - (5 - 2) > r ) Example(expr=Not(GT(Minus(r, Minus(Real(5), Real(2))), r)), is_valid=True, is_sat=True, logic=pysmt.logics.QF_RDL), # x ? 7: (s + -1) * 3 = r Example(expr=Equals( Ite(x, Real(7), Times(Plus(s, Real(-1)), Real(3))), r), is_valid=False, is_sat=True, logic=pysmt.logics.QF_LRA), # # EUF # # rf(5, rg(2)) = 0 Example(expr=Equals(Function(rf, (Real(5), Function(rg, (r, )))), Real(0)), is_valid=False, is_sat=True, logic=pysmt.logics.QF_UFLRA), # (rg(r) = 5 + 2) <-> (rg(r) = 7) Example(expr=Iff(Equals(Function(rg, [r]), Plus(Real(5), Real(2))), Equals(Function(rg, [r]), Real(7))), is_valid=True, is_sat=True, logic=pysmt.logics.QF_UFLRA), # (r = s + 1) & (rg(s) = 5) & (rg(r - 1) = 7) Example(expr=And([ Equals(r, Plus(s, Real(1))), Equals(Function(rg, [s]), Real(5)), Equals(Function(rg, [Minus(r, Real(1))]), Real(7)) ]), is_valid=False, is_sat=False, logic=pysmt.logics.QF_UFLRA), # # BV # # bv_one & bv_zero == bv_zero Example(expr=Equals(BVAnd(BVOne(32), BVZero(32)), BVZero(32)), is_valid=True, is_sat=True, logic=pysmt.logics.QF_BV), # ~(010) == 101 Example(expr=Equals(BVNot(BV("010")), BV("101")), is_valid=True, is_sat=True, logic=pysmt.logics.QF_BV), # "111" xor "000" == "000" Example(expr=Equals(BVXor(BV("111"), BV("000")), BV("000")), is_valid=False, is_sat=False, logic=pysmt.logics.QF_BV), # bv8 :: bv8 < bv_zero Example(expr=BVULT(BVConcat(bv8, bv8), BVZero(16)), is_valid=False, is_sat=False, logic=pysmt.logics.QF_BV), # bv_one[:7] == bv_one Example(expr=Equals(BVExtract(BVOne(32), end=7), BVOne(8)), is_valid=True, is_sat=True, logic=pysmt.logics.QF_BV), # (((bv8 + bv_one) * bv(5)) / bv(5)) > bv(0) Example(expr=BVUGT( BVUDiv(BVMul(BVAdd(bv8, BVOne(8)), BV(5, width=8)), BV(5, width=8)), BVZero(8)), is_valid=False, is_sat=True, logic=pysmt.logics.QF_BV), # bv16 >=u bv(0) Example(expr=BVUGE(bv16, BVZero(16)), is_valid=True, is_sat=True, logic=pysmt.logics.QF_BV), # bv16 >=s bv(0) Example(expr=BVSGE(bv16, BVZero(16)), is_valid=False, is_sat=True, logic=pysmt.logics.QF_BV), # (BV(5) rem BV(2) > bv_zero) /\ (BV(5) rem BV(2) < bv_one) Example(expr=And( BVUGT(BVURem(BV(5, width=32), BV(2, width=32)), BVZero(32)), BVULE(BVURem(BV(5, width=32), BV(2, width=32)), BVOne(32))), is_valid=True, is_sat=True, logic=pysmt.logics.QF_BV), # ((bv_one + (- bv_one)) << 1) >> 1 == bv_one Example(expr=Equals( BVLShr(BVLShl(BVAdd(BVOne(32), BVNeg(BVOne(32))), 1), 1), BVOne(32)), is_valid=False, is_sat=False, logic=pysmt.logics.QF_BV), # bv_one - bv_one == bv_zero Example(expr=Equals(BVSub(BVOne(32), BVOne(32)), BVZero(32)), is_valid=True, is_sat=True, logic=pysmt.logics.QF_BV), # Rotations Example(expr=Equals(BVRor(BVRol(BVOne(32), 1), 1), BVOne(32)), is_valid=True, is_sat=True, logic=pysmt.logics.QF_BV), # Extensions Example(expr=Equals(BVZExt(BVZero(5), 11), BVSExt(BVZero(1), 15)), is_valid=True, is_sat=True, logic=pysmt.logics.QF_BV), # bv16 - bv16 = 0_16 Example(expr=Equals(BVSub(bv16, bv16), BVZero(16)), is_valid=True, is_sat=True, logic=pysmt.logics.QF_BV), # (bv16 - bv16)[0:7] = bv8 Example(expr=Equals(BVExtract(BVSub(bv16, bv16), 0, 7), bv8), is_valid=False, is_sat=True, logic=pysmt.logics.QF_BV), # (bv16[0,7] comp bv8) = bv1 Example(expr=Equals(BVComp(BVExtract(bv16, 0, 7), bv8), BVOne(1)), is_valid=False, is_sat=True, logic=pysmt.logics.QF_BV), # (bv16 comp bv16) = bv0 Example(expr=Equals(BVComp(bv16, bv16), BVZero(1)), is_valid=False, is_sat=False, logic=pysmt.logics.QF_BV), # (bv16 s< bv16) Example(expr=BVSLT(bv16, bv16), is_valid=False, is_sat=False, logic=pysmt.logics.QF_BV), # (bv16 s< 0_16) Example(expr=BVSLT(bv16, BVZero(16)), is_valid=False, is_sat=True, logic=pysmt.logics.QF_BV), # (bv16 u< bv16) Example(expr=BVULT(bv16, bv16), is_valid=False, is_sat=False, logic=pysmt.logics.QF_BV), # (bv16 s< 0_16) Example(expr=BVULT(bv16, BVZero(16)), is_valid=False, is_sat=False, logic=pysmt.logics.QF_BV), # (bv16 | 0_16) = bv16 Example(expr=Equals(BVOr(bv16, BVZero(16)), bv16), is_valid=True, is_sat=True, logic=pysmt.logics.QF_BV), # (bv16 & 0_16) = 0_16 Example(expr=Equals(BVAnd(bv16, BVZero(16)), BVZero(16)), is_valid=True, is_sat=True, logic=pysmt.logics.QF_BV), # 0_16 s< bv16 & ((bv16 s/ -1) s< 0) Example(expr=And(BVSLT(BVZero(16), bv16), BVSLT(BVSDiv(bv16, SBV(-1, 16)), BVZero(16))), is_valid=False, is_sat=True, logic=pysmt.logics.QF_BV), # 0_16 s< bv16 & ((bv16 s% -1) s< 0) Example(expr=And(BVSLT(BVZero(16), bv16), BVSLT(BVSRem(bv16, BVOne(16)), BVZero(16))), is_valid=False, is_sat=False, logic=pysmt.logics.QF_BV), # bv16 u% 1 = 0_16 Example(expr=Equals(BVURem(bv16, BVOne(16)), BVZero(16)), is_valid=True, is_sat=True, logic=pysmt.logics.QF_BV), # bv16 s% 1 = 0_16 Example(expr=Equals(BVSRem(bv16, BVOne(16)), BVZero(16)), is_valid=True, is_sat=True, logic=pysmt.logics.QF_BV), # bv16 s% -1 = 0_16 Example(expr=Equals(BVSRem(bv16, BVNeg(BVOne(16))), BVZero(16)), is_valid=True, is_sat=True, logic=pysmt.logics.QF_BV), # bv16 a>> 0 = bv16 Example(expr=Equals(BVAShr(bv16, BVZero(16)), bv16), is_valid=True, is_sat=True, logic=pysmt.logics.QF_BV), # 0 s<= bv16 & bv16 a>> 1 = bv16 >> 1 Example(expr=And( BVSLE(BVZero(16), bv16), Equals(BVAShr(bv16, BVOne(16)), BVLShr(bv16, BVOne(16)))), is_valid=False, is_sat=True, logic=pysmt.logics.QF_BV), # # Quantification # # forall y . x -> y Example(expr=ForAll([y], Implies(x, y)), is_valid=False, is_sat=True, logic=pysmt.logics.BOOL), # forall p,q . p + q = 0 Example(expr=ForAll([p, q], Equals(Plus(p, q), Int(0))), is_valid=False, is_sat=False, logic=pysmt.logics.LIA), # forall r,s . ((r > 0) & (s > 0)) -> (r - s < r) Example(expr=ForAll([r, s], Implies(And(GT(r, Real(0)), GT(s, Real(0))), (LT(Minus(r, s), r)))), is_valid=True, is_sat=True, logic=pysmt.logics.LRA), # exists x,y . x -> y Example(expr=Exists([x, y], Implies(x, y)), is_valid=True, is_sat=True, logic=pysmt.logics.BOOL), # exists p,q . p + q = 0 Example(expr=Exists([p, q], Equals(Plus(p, q), Int(0))), is_valid=True, is_sat=True, logic=pysmt.logics.LIA), # exists r . forall s . (r - s > r) Example(expr=Exists([r], ForAll([s], GT(Minus(r, s), r))), is_valid=False, is_sat=False, logic=pysmt.logics.LRA), # forall r . exists s . (r - s > r) Example(expr=ForAll([r], Exists([s], GT(Minus(r, s), r))), is_valid=True, is_sat=True, logic=pysmt.logics.LRA), # x /\ forall r. (r + s = 5) Example(expr=And(x, ForAll([r], Equals(Plus(r, s), Real(5)))), is_valid=False, is_sat=False, logic=pysmt.logics.LRA), # # UFLIRA # # ih(r,q) > p /\ (x -> y) Example(expr=And(GT(Function(ih, (r, q)), p), Implies(x, y)), is_valid=False, is_sat=True, logic=pysmt.logics.QF_UFLIRA), # ( (p - 3) = q ) -> ( ih(r, q + 3) > p \/ ih(r, p) <= p ) Example(expr=Implies( Equals(Minus(p, Int(3)), q), Or(GT(Function(ih, (r, Plus(q, Int(3)))), p), LE(Function(ih, (r, p)), p))), is_valid=True, is_sat=True, logic=pysmt.logics.QF_UFLIRA), # ( (ToReal(p - 3) = r) /\ (ToReal(q) = r) ) -> # ( ( ih(ToReal(p - 3), q + 3) > p ) \/ (ih(r, p) <= p) ) Example(expr=Implies( And(Equals(ToReal(Minus(p, Int(3))), r), Equals(ToReal(q), r)), Or( GT( Function(ih, (ToReal(Minus(p, Int(3))), Plus(q, Int(3)))), p), LE(Function(ih, (r, p)), p))), is_valid=True, is_sat=True, logic=pysmt.logics.QF_UFLIRA), # ! ( (ToReal(p - 3) = r /\ ToReal(q) = r) -> # ( ih(ToReal(p - 3), q + 3) > p \/ # ih(r,p) <= p ) ) Example(expr=Not( Implies( And(Equals(ToReal(Minus(p, Int(3))), r), Equals(ToReal(q), r)), Or( GT( Function( ih, (ToReal(Minus(p, Int(3))), Plus(q, Int(3)))), p), LE(Function(ih, (r, p)), p)))), is_valid=False, is_sat=False, logic=pysmt.logics.QF_UFLIRA), # Test complex names Example(expr=And( Symbol("Did you know that any string works? #yolo"), Symbol("10"), Symbol("|#somesolverskeepthe||"), Symbol(" ")), is_valid=False, is_sat=True, logic=pysmt.logics.QF_BOOL), ] return result
def probably_expr_to_pysmt(expr, pysmt_infinity_variable=None, treat_minus_as_monus=False, monus_euf=None, toReal=False): """ Convert a Probably expression to a pysmt expression. Infinity must not occur in a composed arithmetic expression. :param expr: The Propbably expression that is to be converted. :param pysmt_infinity_variable: The pysmt variable used to represent infinity. :param toReal: Whether variables and NatLitExpr shall be cast to Real or not. :param treat_minus_as_monus: Whether to repalace every expression of the form a - b by monus_euf(a,b) :param monus_euf: The uninterpreted function that is to be used for monus. :return: The resulting PySMT expression. """ env = get_env() if isinstance(expr, BoolLitExpr): if expr.value == True: return TRUE() elif expr.value == False: return FALSE() else: raise Exception("Unkown expression value.") elif isinstance(expr, NatLitExpr): return Int(expr.value) if not toReal else Real(expr.value) elif isinstance(expr, FloatLitExpr): # This value might be infinity if expr.is_infinite(): if pysmt_infinity_variable == None: raise Exception( "If infinity occurs in an arithmetic expression, then pysmt_infinity_variable must not be none." ) return pysmt_infinity_variable else: return Real(expr.to_fraction()) elif isinstance(expr, VarExpr): return env.formula_manager.get_symbol( expr.var) if not toReal else ToReal( env.formula_manager.get_symbol(expr.var)) elif isinstance(expr, TickExpr): if not isinstance(expr.expr, NatLitExpr): raise Exception( "Currently we allow for constants in tick(..) expressions only." ) else: return probably_expr_to_pysmt(expr.expr, pysmt_infinity_variable, treat_minus_as_monus, monus_euf, toReal) elif isinstance(expr, BinopExpr): if expr.operator == Binop.OR: return Or( probably_expr_to_pysmt(expr.lhs, pysmt_infinity_variable, treat_minus_as_monus, monus_euf, toReal), probably_expr_to_pysmt(expr.rhs, pysmt_infinity_variable, treat_minus_as_monus, monus_euf, toReal)) if expr.operator == Binop.AND: return And( probably_expr_to_pysmt(expr.lhs, pysmt_infinity_variable, treat_minus_as_monus, monus_euf, toReal), probably_expr_to_pysmt(expr.rhs, pysmt_infinity_variable, treat_minus_as_monus, monus_euf, toReal)) if expr.operator == Binop.LEQ: return LE( probably_expr_to_pysmt(expr.lhs, pysmt_infinity_variable, treat_minus_as_monus, monus_euf, toReal), probably_expr_to_pysmt(expr.rhs, pysmt_infinity_variable, treat_minus_as_monus, monus_euf, toReal)) if expr.operator == Binop.LE: return LT( probably_expr_to_pysmt(expr.lhs, pysmt_infinity_variable, treat_minus_as_monus, monus_euf, toReal), probably_expr_to_pysmt(expr.rhs, pysmt_infinity_variable, treat_minus_as_monus, monus_euf, toReal)) if expr.operator == Binop.EQ: lhs = probably_expr_to_pysmt(expr.lhs, pysmt_infinity_variable, treat_minus_as_monus, monus_euf, toReal) rhs = probably_expr_to_pysmt(expr.rhs, pysmt_infinity_variable, treat_minus_as_monus, monus_euf, toReal) return EqualsOrIff(lhs, rhs) if expr.operator == Binop.PLUS: summand_1 = probably_expr_to_pysmt(expr.lhs, pysmt_infinity_variable, treat_minus_as_monus, monus_euf, toReal) summand_2 = probably_expr_to_pysmt(expr.rhs, pysmt_infinity_variable, treat_minus_as_monus, monus_euf, toReal) if summand_1 == pysmt_infinity_variable or summand_2 == pysmt_infinity_variable: raise Exception( "Infinity must not occur in a composed arithmetic expression." ) return Plus(summand_1, summand_2) if expr.operator == Binop.MINUS: min_1 = probably_expr_to_pysmt(expr.lhs, pysmt_infinity_variable, treat_minus_as_monus, monus_euf, toReal) min_2 = probably_expr_to_pysmt(expr.rhs, pysmt_infinity_variable, treat_minus_as_monus, monus_euf, toReal) if min_1 == pysmt_infinity_variable or min_2 == pysmt_infinity_variable: raise Exception( "Infinity must not occur in a composed arithmetic expression." ) # Do we have to treat minus as monus? if treat_minus_as_monus: if monus_euf == None: raise Exception( "If minus is to be treated as monus, then a monus_euf has to be provided." ) monus_expr = Function(monus_euf, (min_1, min_2)) if toReal: encountered_real_monus_pairs.add((min_1, min_2)) else: encountered_monus_pairs.add((min_1, min_2)) return monus_expr else: return Minus(min_1, min_2) if expr.operator == Binop.TIMES: fac_1 = probably_expr_to_pysmt(expr.lhs, pysmt_infinity_variable, treat_minus_as_monus, monus_euf, toReal) fac_2 = probably_expr_to_pysmt(expr.rhs, pysmt_infinity_variable, treat_minus_as_monus, monus_euf, toReal) if fac_1 == pysmt_infinity_variable or fac_2 == pysmt_infinity_variable: raise Exception( "Infinity must not occur in a composed arithmetic expression." ) return Times(fac_1, fac_2) elif isinstance(expr, UnopExpr): if expr.operator == Unop.NEG: return Not( probably_expr_to_pysmt(expr.expr, pysmt_infinity_variable, treat_minus_as_monus, monus_euf, toReal)) elif expr.operator == Unop.IVERSON: return probably_expr_to_pysmt(expr.expr, pysmt_infinity_variable, treat_minus_as_monus, monus_euf, toReal) else: raise Exception("Unsupported Unop Operator") else: raise Exception("Invalid expression {expr}")