1 /*++
2 Copyright (c) 2006 Microsoft Corporation
3
4 Module Name:
5
6 var_subst.cpp
7
8 Abstract:
9
10 <abstract>
11
12 Author:
13
14 Leonardo de Moura (leonardo) 2008-06-12.
15
16 Revision History:
17
18 --*/
19 #include "ast/rewriter/var_subst.h"
20 #include "ast/ast_pp.h"
21 #include "ast/arith_decl_plugin.h"
22 #include "ast/bv_decl_plugin.h"
23 #include "ast/array_decl_plugin.h"
24 #include "ast/for_each_expr.h"
25 #include "ast/reg_decl_plugins.h"
26
27 namespace find_q {
28 struct proc {
29 quantifier * m_q;
procfind_q::proc30 proc():m_q(nullptr) {}
operator ()find_q::proc31 void operator()(var * n) {}
operator ()find_q::proc32 void operator()(app * n) {}
operator ()find_q::proc33 void operator()(quantifier * n) { m_q = n; }
34 };
35 };
36
find_quantifier(expr * n)37 quantifier * find_quantifier(expr * n) {
38 find_q::proc p;
39 for_each_expr(p, n);
40 return p.m_q;
41 }
42
tst_instantiate(ast_manager & m,expr * f)43 void tst_instantiate(ast_manager & m, expr * f) {
44 if (is_quantifier(f)) {
45 tst_instantiate(m, to_quantifier(f)->get_expr());
46 return;
47 }
48 quantifier * q = find_quantifier(f);
49 if (q) {
50 expr_ref_vector cnsts(m);
51 for (unsigned i = 0; i < q->get_num_decls(); i++)
52 cnsts.push_back(m.mk_fresh_const("a", q->get_decl_sort(i)));
53 expr_ref r = instantiate(m, q, cnsts.c_ptr());
54 TRACE("var_subst", tout << "quantifier:\n" << mk_pp(q, m) << "\nresult:\n" << mk_pp(r, m) << "\n";);
55 }
56 }
57
tst_subst(ast_manager & m)58 void tst_subst(ast_manager& m) {
59 func_decl_ref p(m);
60 sort_ref s(m);
61 obj_ref<var, ast_manager> x(m), y(m), z(m), u(m), v(m);
62 expr_ref e1(m), e2(m), e3(m);
63 expr_ref t1(m), t2(m), t3(m);
64 s = m.mk_uninterpreted_sort(symbol("S"));
65 sort* ss[2] = { s.get(), s.get() };
66 symbol names[2] = { symbol("y"), symbol("x") };
67 p = m.mk_func_decl(symbol("p"), 2, ss, m.mk_bool_sort());
68 x = m.mk_var(0, s);
69 y = m.mk_var(1, s);
70 z = m.mk_var(2, s);
71 u = m.mk_var(3, s);
72 v = m.mk_var(4, s);
73 e1 = m.mk_and(m.mk_app(p, x.get(), y.get()), m.mk_app(p, z.get(), u.get()));
74 e2 = m.mk_forall(1, ss, names, e1);
75 t1 = m.mk_forall(1, ss, names,
76 m.mk_and(m.mk_app(p, x.get(), z.get()), m.mk_app(p, y.get(), u.get())));
77 t2 = m.mk_forall(2, ss, names,
78 m.mk_and(m.mk_app(p, x.get(), y.get()), m.mk_app(p, u.get(), z.get())));
79
80 var_subst subst(m);
81 expr_ref_vector sub1(m);
82 sub1.push_back(x);
83 sub1.push_back(y);
84 // replace #1 -> #2, #2 -> #1
85 e3 = subst(e2, 2, sub1.c_ptr());
86 std::cout << mk_pp(e2, m) << "\n";
87 std::cout << mk_pp(e3, m) << "\n";
88 std::cout << mk_pp(t1, m) << "\n";
89 ENSURE(e3.get() == t1.get());
90
91 // replace #2 -> #3, #3 -> #2
92 e2 = m.mk_forall(2, ss, names, e1);
93 e3 = subst(e2, 2, sub1.c_ptr());
94 std::cout << mk_pp(e2, m) << "\n";
95 std::cout << mk_pp(e3, m) << "\n";
96 std::cout << mk_pp(t2, m) << "\n";
97 ENSURE(e3.get() == t2.get());
98
99 }
100
tst_var_subst()101 void tst_var_subst() {
102 ast_manager m;
103 reg_decl_plugins(m);
104 tst_subst(m);
105 }
106