Esempio n. 1
0
        /// <summary>
        /// Find x and y such that: x ^ y - 103 == x * y
        /// </summary>
        public static void BitvectorExample2()
        {
            print("BitvectorExample2");
            using var svc = Z3Api.Create();

            var bvSize = default(N32);
            /* construct x ^ y - 103 == x * y */
            var x       = svc.BvConst("x", bvSize);
            var y       = svc.BvConst("y", bvSize);
            var x_xor_y = svc.XOr(x, y);
            var c103    = svc.BvNumeral("103", bvSize);
            var lhs     = svc.Sub(x_xor_y, c103);
            var rhs     = svc.Mul(x, y);
            var ctr     = svc.Eq(lhs, rhs);

            print("find values of x and y, such that x ^ y - 103 == x * y");

            /* find a model (i.e., values for x an y that satisfy the constraint */
            Model m = Check(svc, ctr, Status.SATISFIABLE);

            foreach (var e in m.Consts)
            {
                print($"{e.Key.Name}:{e.Key.ASTKind} = {e.Value}");
            }
        }
Esempio n. 2
0
        public static void BvExample1()
        {
            using var svc = Z3Api.Create();
            var x    = svc.BvVal(3);
            var y    = svc.BvVal(5);
            var z    = svc.Or(x, y);
            var eval = z.Simplify();

            inform($"{z.SExpr()} = {eval}:{eval.ASTKind}");
        }
Esempio n. 3
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        public static void EnumExamples()
        {
            using var svc = Z3Api.Create();
            var choices = svc.Enum("Choices", "ChoiceA", "ChoiceB", "ChoiceC");

            for (var i = 0u; i < choices.Consts.Length; i++)
            {
                inform($"Choice {i} = {choices.Const(i)}");
            }
        }
Esempio n. 4
0
        /// <summary>
        /// Simple bit-vector example.
        /// </summary>
        /// <remarks>
        /// This example disproves that x - 10 &lt;= 0 IFF x &lt;= 10 for (32-bit) machine integers
        /// </remarks>
        public static void BitvectorExample1()
        {
            var ctx = new Z3.Context();

            using var svc = Z3Api.Own(ctx);


            var        bv_type     = ctx.MkBitVecSort(32);
            var        x           = (BitVecExpr)ctx.MkConst("x", bv_type);
            var        zero        = (BitVecNum)ctx.MkNumeral("0", bv_type);
            BitVecNum  ten         = ctx.MkBV(10, 32);
            BitVecExpr x_minus_ten = ctx.MkBVSub(x, ten);
            /* bvsle is signed less than or equal to */
            BoolExpr c1  = ctx.MkBVSLE(x, ten);
            BoolExpr c2  = ctx.MkBVSLE(x_minus_ten, zero);
            BoolExpr thm = ctx.MkIff(c1, c2);

            print("disprove: x - 10 <= 0 IFF x <= 10 for (32-bit) machine integers");
            Disprove(ctx, thm);
        }