C++ ast_manager::mk_eq方法代码示例

static app_ref generate_ineqs(ast_manager& m, sort* s, vector<expr_ref_vector>& cs, bool mods_too) {
    arith_util a(m);
    app_ref_vector vars(m), nums(m);
    vars.push_back(m.mk_const(symbol("x"), s));
    vars.push_back(m.mk_const(symbol("y"), s));
    vars.push_back(m.mk_const(symbol("z"), s));
    vars.push_back(m.mk_const(symbol("u"), s));
    vars.push_back(m.mk_const(symbol("v"), s));
    vars.push_back(m.mk_const(symbol("w"), s));
    nums.push_back(a.mk_numeral(rational(1),  s));
    nums.push_back(a.mk_numeral(rational(2),  s));
    nums.push_back(a.mk_numeral(rational(3),  s));
    
    app* x = vars[0].get();
    app* y = vars[1].get();
    // app* z = vars[2].get();
    // 
    // ax <= by, ax < by, not (ax >= by), not (ax > by)
    // 
    cs.push_back(mk_ineqs(x, vars[1].get(), nums));
    cs.push_back(mk_ineqs(x, vars[2].get(), nums));
    cs.push_back(mk_ineqs(x, vars[3].get(), nums));
    cs.push_back(mk_ineqs(x, vars[4].get(), nums));
    cs.push_back(mk_ineqs(x, vars[5].get(), nums));

    if (mods_too) {
        expr_ref_vector mods(m);
        expr_ref zero(a.mk_numeral(rational(0), s), m);
        mods.push_back(m.mk_true());
        for (unsigned j = 0; j < nums.size(); ++j) {
            mods.push_back(m.mk_eq(a.mk_mod(a.mk_add(a.mk_mul(nums[j].get(),x), y), nums[1].get()), zero));
        }
        cs.push_back(mods);
        mods.resize(1);
        for (unsigned j = 0; j < nums.size(); ++j) {
            mods.push_back(m.mk_eq(a.mk_mod(a.mk_add(a.mk_mul(nums[j].get(),x), y), nums[2].get()), zero));
        }
        cs.push_back(mods);
    }
    return app_ref(x, m);
}

/**
   \brief return two terms that are equal in the model.
   The distinct term t is false in model, so there 
   are at least two arguments of t that are equal in the model.
*/
expr_ref project_plugin::pick_equality(ast_manager& m, model& model, expr* t) {
    SASSERT(m.is_distinct(t));
    expr_ref val(m);
    expr_ref_vector vals(m);
    obj_map<expr, expr*> val2expr;
    app* alit = to_app(t);
    for (unsigned i = 0; i < alit->get_num_args(); ++i) {
        expr* e1 = alit->get_arg(i), *e2;
        VERIFY(model.eval(e1, val));
        if (val2expr.find(val, e2)) {
            return expr_ref(m.mk_eq(e1, e2), m);
        }
        val2expr.insert(val, e1);
        vals.push_back(val);
    }
    UNREACHABLE();
    return expr_ref(0, m);
}

/**
   \brief Little HACK for simplifying injectivity axioms
   
   \remark It is not covering all possible cases.
*/
bool simplify_inj_axiom(ast_manager & m, quantifier * q, expr_ref & result) {
    expr * n = q->get_expr();
    expr* arg1 = nullptr, * arg2 = nullptr, *narg = nullptr;
    expr* app1 = nullptr, * app2 = nullptr;
    expr* var1 = nullptr, * var2 = nullptr;
    if (is_forall(q) && m.is_or(n, arg1, arg2)) {
        if (m.is_not(arg2)) 
            std::swap(arg1, arg2);
        if (m.is_not(arg1, narg) && 
            m.is_eq(narg, app1, app2) && 
            m.is_eq(arg2, var1, var2)) {
            if (is_app(app1) &&
                is_app(app2) && 
                to_app(app1)->get_decl() == to_app(app2)->get_decl() &&
                to_app(app1)->get_num_args() == to_app(app2)->get_num_args() &&
                to_app(app1)->get_family_id() == null_family_id &&
                to_app(app1)->get_num_args() > 0 &&
                is_var(var1) && 
                is_var(var2) && 
                var1 != var2) {
                app * f1          = to_app(app1);
                app * f2          = to_app(app2);
                bool found_vars   = false;
                unsigned num      = f1->get_num_args();
                unsigned idx      = UINT_MAX;
                unsigned num_vars = 1;
                for (unsigned i = 0; i < num; i++) {
                    expr  * c1 = f1->get_arg(i);
                    expr  * c2 = f2->get_arg(i);
                    if (!is_var(c1) && !is_uninterp_const(c1))
                        return false;
                    if ((c1 == var1 && c2 == var2) || (c1 == var2 && c2 == var1)) {
                        if (found_vars)
                            return false;
                        found_vars = true;
                        idx = i;
                    }
                    else if (c1 == c2 && c1 != var1 && c1 != var2) {
                        if (is_var(c1)) {
                            ++num_vars;
                        }
                    }
                    else {
                        return false;
                    }
                }
                if (found_vars && !has_free_vars(q)) {
                    TRACE("inj_axiom", 
                          tout << "Cadidate for simplification:\n" << mk_ll_pp(q, m) << mk_pp(app1, m) << "\n" << mk_pp(app2, m) << "\n" <<
                          mk_pp(var1, m) << "\n" << mk_pp(var2, m) << "\nnum_vars: " << num_vars << "\n";);
                    // Building new (optimized) axiom
                    func_decl * decl      = f1->get_decl();
                    unsigned var_idx      = 0;
                    ptr_buffer<expr> f_args, inv_vars;
                    ptr_buffer<sort> decls;
                    buffer<symbol>   names;
                    
                    expr * var            = nullptr;
                    for (unsigned i = 0; i < num; i++) {
                        expr * c = f1->get_arg(i);
                        if (is_var(c)) {
                            names.push_back(symbol(i));
                            sort * s = decl->get_domain(i);
                            decls.push_back(s);
                            expr * new_c = m.mk_var(var_idx, s);
                            var_idx++;
                            f_args.push_back(new_c);
                            if (i == idx) {
                                var = new_c;
                            }
                            else {
                                inv_vars.push_back(new_c);
                            }
                        }
                        else {
                            SASSERT(is_uninterp_const(c));
                            f_args.push_back(c);
                        }
                    }
                    SASSERT(var != 0);
                    app * f    = m.mk_app(decl, f_args.size(), f_args.c_ptr());

                    ptr_vector<sort>  domain;
                    inv_vars.push_back(f);
                    for (unsigned i = 0; i < inv_vars.size(); ++i) {
                        domain.push_back(m.get_sort(inv_vars[i]));
                    }
                    sort * d              = decl->get_domain(idx);
                    func_decl * inv_decl  = m.mk_fresh_func_decl("inj", domain.size(), domain.c_ptr(), d);
                    
                    expr * proj = m.mk_app(inv_decl, inv_vars.size(), inv_vars.c_ptr());
                    expr * eq   = m.mk_eq(proj, var);
                    expr * p    = m.mk_pattern(f);
                    
                    // decls are in the wrong order...
//.........这里部分代码省略.........