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teething stage for from/to code axiomatization
This commit is contained in:
Nikolaj Bjorner 2021-02-09 16:38:03 -08:00
parent 692f159af8
commit 5c04b9eee2

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@ -804,6 +804,7 @@ void seq_axioms::add_is_digit_axiom(expr* n) {
/**
len(e) = 1 => 0 <= to_code(e) <= max_code
len(e) = 1 => from_code(to_code(e)) = e
len(e) != 1 => to_code(e) = -1
*/
void seq_axioms::add_str_to_code_axiom(expr* n) {
@ -812,6 +813,8 @@ void seq_axioms::add_str_to_code_axiom(expr* n) {
literal len_is1 = mk_eq(mk_len(e), a.mk_int(1));
add_axiom(~len_is1, mk_ge(n, 0));
add_axiom(~len_is1, mk_le(n, seq.max_char()));
if (!seq.str.is_from_code(e))
add_axiom(~len_is1, mk_eq(e, seq.str.mk_from_code(n)));
add_axiom(len_is1, mk_eq(n, a.mk_int(-1)));
}
@ -827,7 +830,8 @@ void seq_axioms::add_str_from_code_axiom(expr* n) {
literal le = mk_le(e, seq.max_char());
literal emp = mk_literal(seq.str.mk_is_empty(n));
add_axiom(~ge, ~le, mk_eq(mk_len(n), a.mk_int(1)));
add_axiom(~ge, ~le, mk_eq(seq.str.mk_to_code(n), e));
if (!seq.str.is_to_code(e))
add_axiom(~ge, ~le, mk_eq(seq.str.mk_to_code(n), e));
add_axiom(ge, emp);
add_axiom(le, emp);
}