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Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>
This commit is contained in:
Nikolaj Bjorner 2018-11-23 13:49:09 -08:00
parent 8d940f64b8
commit 801026937d
2 changed files with 33 additions and 13 deletions

View file

@ -2292,9 +2292,30 @@ bool theory_seq::simplify_eq(expr_ref_vector& ls, expr_ref_vector& rs, dependenc
return true;
}
bool theory_seq::solve_nth_eq(expr_ref_vector& ls, expr_ref_vector& rs, dependency* deps) {
if (ls.size() != 1) return false;
expr_ref l(ls.get(0), m);
bool theory_seq::solve_itos(expr_ref_vector const& ls, expr_ref_vector const& rs, dependency* dep) {
expr* e = nullptr;
if (ls.size() == 1 && rs.empty() && m_util.str.is_itos(ls[0], e)) {
literal lit = mk_simplified_literal(m_autil.mk_le(e, m_autil.mk_int(-1)));
propagate_lit(dep, 0, nullptr, lit);
return true;
}
if (rs.size() == 1 && ls.empty() && m_util.str.is_itos(rs[0], e)) {
literal lit = mk_simplified_literal(m_autil.mk_le(e, m_autil.mk_int(-1)));
propagate_lit(dep, 0, nullptr, lit);
return true;
}
return false;
}
bool theory_seq::solve_nth_eq(expr_ref_vector const& ls, expr_ref_vector const& rs, dependency* dep) {
if (ls.size() != 1 || rs.size() <= 1) {
return false;
}
expr* l = ls.get(0);
rational val;
if (!get_length(l, val) || val != rational(rs.size())) {
return false;
}
for (unsigned i = 0; i < rs.size(); ++i) {
unsigned k = 0;
expr* ru = nullptr, *r = nullptr;
@ -2303,12 +2324,7 @@ bool theory_seq::solve_nth_eq(expr_ref_vector& ls, expr_ref_vector& rs, dependen
}
return false;
}
add_solution(l, mk_concat(rs, m.get_sort(l)), deps);
expr_ref r(m_autil.mk_int(rs.size()), m);
ls.reset();
rs.reset();
ls.push_back(m_util.str.mk_length(l));
rs.push_back(r);
add_solution(l, mk_concat(rs, m.get_sort(l)), dep);
return true;
}
@ -2467,10 +2483,13 @@ bool theory_seq::solve_eq(expr_ref_vector const& l, expr_ref_vector const& r, de
return true;
}
if (!ctx.inconsistent() && solve_nth_eq(ls, rs, deps)) {
change = true;
return true;
}
if (!ctx.inconsistent() && solve_nth_eq(rs, ls, deps)) {
change = true;
return true;
}
if (!ctx.inconsistent() && solve_itos(rs, ls, deps)) {
return true;
}
if (!ctx.inconsistent() && change) {
// The propagation step from arithmetic state (e.g. length offset) to length constraints
@ -3433,7 +3452,7 @@ bool theory_seq::add_stoi_val_axiom(expr* e) {
}
if (!m_stoi_axioms.contains(val)) {
m_stoi_axioms.insert(val);
if (!val.is_minus_one()) {
if (!val.is_neg()) {
app_ref e1(m_util.str.mk_string(symbol(val.to_string().c_str())), m);
expr_ref n1(arith_util(m).mk_numeral(val, true), m);
literal eq1 = mk_preferred_eq(e, n1);

View file

@ -432,7 +432,8 @@ namespace smt {
bool simplify_eq(expr_ref_vector& l, expr_ref_vector& r, dependency* dep);
bool solve_unit_eq(expr* l, expr* r, dependency* dep);
bool solve_unit_eq(expr_ref_vector const& l, expr_ref_vector const& r, dependency* dep);
bool solve_nth_eq(expr_ref_vector& ls, expr_ref_vector& rs, dependency* dep);
bool solve_nth_eq(expr_ref_vector const& ls, expr_ref_vector const& rs, dependency* dep);
bool solve_itos(expr_ref_vector const& ls, expr_ref_vector const& rs, dependency* dep);
bool is_binary_eq(expr_ref_vector const& l, expr_ref_vector const& r, expr_ref& x, ptr_vector<expr>& xunits, ptr_vector<expr>& yunits, expr_ref& y);
bool is_quat_eq(expr_ref_vector const& ls, expr_ref_vector const& rs, expr_ref& x1, expr_ref_vector& xs, expr_ref& x2, expr_ref& y1, expr_ref_vector& ys, expr_ref& y2);
bool is_ternary_eq(expr_ref_vector const& ls, expr_ref_vector const& rs, expr_ref& x, expr_ref_vector& xs, expr_ref& y1, expr_ref_vector& ys, expr_ref& y2, bool flag1);