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tidy

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Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>
This commit is contained in:
Nikolaj Bjorner 2020-08-01 16:54:05 -07:00
parent 8137143ada
commit 06f34bd42b
1 changed files with 36 additions and 37 deletions
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73
src/smt/seq_regex.cpp
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@ -157,47 +157,46 @@ namespace smt {
*/
expr_ref seq_regex::get_overapprox_regex(expr* s) {
expr_ref s_to_re(re().mk_to_re(s), m);
expr_ref epsilon(re().mk_epsilon(m.get_sort(s)), m);
expr_ref dotstar(re().mk_full_seq(m.get_sort(s_to_re)), m);
if (m.is_value(s)) {
return s_to_re;
}
else {
if (m.is_value(s))
s_to_re;
if (str().is_concat(s)) {
expr_ref_vector es(m);
expr_ref s_approx(m);
if (str().is_concat(s)) {
str().get_concat(s, es);
//here it is known that es is nonempty or else s would be a value
expr_ref e_approx(m), last(m);
for (expr* e : es) {
e_approx = get_overapprox_regex(e);
if (!s_approx)
s_approx = e_approx;
else if (last != dotstar || e_approx != dotstar)
s_approx = re().mk_concat(e_approx, s_approx);
last = e_approx;
}
return s_approx;
}
else if (m.is_ite(s)) {
s_approx = get_overapprox_regex(to_app(s)->get_arg(1));
//if either branch approximates to .* then the result is also .*
if (!re().is_full_seq(s_approx)) {
expr_ref r2 = get_overapprox_regex(to_app(s)->get_arg(2));
if (re().is_full_seq(r2)) {
s_approx = r2;
}
else if (s_approx != r2) {
s_approx = re().mk_union(s_approx, r2);
}
}
return s_approx;
}
else {
// TBD: other app expressions that can be approximated
return dotstar;
str().get_concat(s, es);
expr_ref s_approx(m), e_approx(m), last(m);
for (expr* e : es) {
e_approx = get_overapprox_regex(e);
if (!s_approx)
s_approx = e_approx;
else if (last != dotstar || e_approx != dotstar)
s_approx = re().mk_concat(s_approx, e_approx);
last = e_approx;
}
if (!s_approx)
s_approx = re().mk_epsilon(m.get_sort(s));
return s_approx;
}
expr* c = nullptr, *r1 = nullptr, *r2 = nullptr;
if (m.is_ite(s, c, r1, r2)) {
// if either branch approximates to .* then the result is also .*
expr_ref s_approx1 = get_overapprox_regex(r1);
if (re().is_full_seq(s_approx1))
return s_approx1;
expr_ref s_approx2 = get_overapprox_regex(r2);
if (re().is_full_seq(s_approx2))
return s_approx2;
return expr_ref(re().mk_union(s_approx1, s_approx2), m);
}
// TBD: other app expressions that can be approximated
return dotstar;
}
/**