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mirror of https://github.com/Z3Prover/z3 synced 2025-04-13 12:28:44 +00:00
This commit is contained in:
Nikolaj Bjorner 2016-07-08 17:57:12 -07:00
commit 59865f5502
7 changed files with 92 additions and 20 deletions

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@ -802,8 +802,8 @@ namespace z3 {
friend expr implies(expr const & a, bool b);
friend expr implies(bool a, expr const & b);
friend expr or(expr_vector const& args);
friend expr and(expr_vector const& args);
friend expr mk_or(expr_vector const& args);
friend expr mk_and(expr_vector const& args);
friend expr ite(expr const & c, expr const & t, expr const & e);
@ -1501,13 +1501,13 @@ namespace z3 {
return expr(ctx, r);
}
inline expr or(expr_vector const& args) {
inline expr mk_or(expr_vector const& args) {
array<Z3_ast> _args(args);
Z3_ast r = Z3_mk_or(args.ctx(), _args.size(), _args.ptr());
args.check_error();
return expr(args.ctx(), r);
}
inline expr and(expr_vector const& args) {
inline expr mk_and(expr_vector const& args) {
array<Z3_ast> _args(args);
Z3_ast r = Z3_mk_and(args.ctx(), _args.size(), _args.ptr());
args.check_error();

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@ -1515,6 +1515,11 @@ bool seq_rewriter::reduce_eq(expr_ref_vector& ls, expr_ref_vector& rs, expr_ref_
unsigned szl = ls.size() - head1, szr = rs.size() - head2;
expr* const* _ls = ls.c_ptr() + head1, * const* _rs = rs.c_ptr() + head2;
if (solve_itos(szl, _ls, szr, _rs, lhs, rhs, is_sat)) {
ls.reset(); rs.reset();
change = true;
return is_sat;
}
if (length_constrained(szl, _ls, szr, _rs, lhs, rhs, is_sat)) {
ls.reset(); rs.reset();
@ -1679,6 +1684,56 @@ bool seq_rewriter::min_length(unsigned n, expr* const* es, unsigned& len) {
return bounded;
}
bool seq_rewriter::is_string(unsigned n, expr* const* es, zstring& s) const {
zstring s1;
expr* e;
bv_util bv(m());
rational val;
unsigned sz;
for (unsigned i = 0; i < n; ++i) {
if (m_util.str.is_string(es[i], s1)) {
s = s + s1;
}
else if (m_util.str.is_unit(es[i], e) && bv.is_numeral(e, val, sz)) {
s = s + zstring(val.get_unsigned());
}
else {
return false;
}
}
return true;
}
bool seq_rewriter::solve_itos(unsigned szl, expr* const* ls, unsigned szr, expr* const* rs,
expr_ref_vector& lhs, expr_ref_vector& rhs, bool& is_sat) {
expr* l, *r;
if (szl == 1 && m_util.str.is_itos(ls[0], l)) {
if (szr == 1 && m_util.str.is_itos(rs[0], r)) {
lhs.push_back(l);
rhs.push_back(r);
is_sat = true;
return true;
}
zstring s;
if (is_string(szr, rs, s)) {
std::string s1 = s.encode();
rational r(s1.c_str());
if (s1 == r.to_string()) {
lhs.push_back(l);
rhs.push_back(m_autil.mk_numeral(r, true));
return true;
}
}
}
if (szr == 1 && m_util.str.is_itos(rs[0], r)) {
return solve_itos(szr, rs, szl, ls, rhs, lhs, is_sat);
}
return false;
}
bool seq_rewriter::length_constrained(unsigned szl, expr* const* l, unsigned szr, expr* const* r,
expr_ref_vector& lhs, expr_ref_vector& rhs, bool& is_sat) {
is_sat = true;

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@ -125,15 +125,20 @@ class seq_rewriter {
expr_ref_vector& lhs, expr_ref_vector& rhs, bool& is_sat);
bool length_constrained(unsigned n, expr* const* l, unsigned m, expr* const* r,
expr_ref_vector& lhs, expr_ref_vector& rhs, bool& is_sat);
bool solve_itos(unsigned n, expr* const* l, unsigned m, expr* const* r,
expr_ref_vector& lhs, expr_ref_vector& rhs, bool& is_sat);
bool min_length(unsigned n, expr* const* es, unsigned& len);
expr* concat_non_empty(unsigned n, expr* const* es);
bool is_string(unsigned n, expr* const* es, zstring& s) const;
void add_next(u_map<expr*>& next, expr_ref_vector& trail, unsigned idx, expr* cond);
bool is_sequence(expr* e, expr_ref_vector& seq);
bool is_sequence(eautomaton& aut, expr_ref_vector& seq);
bool is_epsilon(expr* e) const;
void split_units(expr_ref_vector& lhs, expr_ref_vector& rhs);
public:
seq_rewriter(ast_manager & m, params_ref const & p = params_ref()):
m_util(m), m_autil(m), m_re2aut(m), m_es(m), m_lhs(m), m_rhs(m) {

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@ -822,16 +822,6 @@ app* seq_util::str::mk_char(char ch) {
return mk_char(s, 0);
}
bool seq_util::str::is_char(expr* n, zstring& c) const {
if (u.is_char(n)) {
c = zstring(to_app(n)->get_decl()->get_parameter(0).get_symbol().bare_str());
return true;
}
else {
return false;
}
}
bool seq_util::str::is_string(expr const* n, zstring& s) const {
if (is_string(n)) {
s = zstring(to_app(n)->get_decl()->get_parameter(0).get_symbol().bare_str());

View file

@ -250,7 +250,6 @@ public:
}
bool is_string(expr const* n, zstring& s) const;
bool is_char(expr* n, zstring& s) const;
bool is_empty(expr const* n) const { symbol s;
return is_app_of(n, m_fid, OP_SEQ_EMPTY) || (is_string(n, s) && !s.is_numerical() && *s.bare_str() == 0);

View file

@ -2197,16 +2197,37 @@ bool theory_seq::check_int_string() {
if (m_util.str.is_itos(e) && add_itos_axiom(e)) {
change = true;
}
else if (m_util.str.is_stoi(e, n)) {
// not (yet) handled.
// we would check that in the current proto-model
// the string at 'n', when denoting integer would map to the
// proper integer.
else if (m_util.str.is_stoi(e, n) && add_stoi_axiom(e)) {
change = true;
}
}
return change;
}
bool theory_seq::add_stoi_axiom(expr* e) {
context& ctx = get_context();
expr* n;
rational val;
VERIFY(m_util.str.is_stoi(e, n));
if (get_value(e, val) && !m_stoi_axioms.contains(val)) {
m_stoi_axioms.insert(val);
if (!val.is_minus_one()) {
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_eq(e, n1, false);
literal eq2 = mk_eq(n, e1, false);
add_axiom(~eq1, eq2);
add_axiom(~eq2, eq1);
ctx.force_phase(eq1);
ctx.force_phase(eq2);
m_trail_stack.push(insert_map<theory_seq, rational_set, rational>(m_stoi_axioms, val));
m_trail_stack.push(push_replay(alloc(replay_axiom, m, e)));
return true;
}
}
return false;
}
bool theory_seq::add_itos_axiom(expr* e) {
context& ctx = get_context();
rational val;

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@ -308,6 +308,7 @@ namespace smt {
bool m_incomplete; // is the solver (clearly) incomplete for the fragment.
expr_ref_vector m_int_string;
rational_set m_itos_axioms;
rational_set m_stoi_axioms;
obj_hashtable<expr> m_length; // is length applied
scoped_ptr_vector<apply> m_replay; // set of actions to replay
model_generator* m_mg;
@ -493,6 +494,7 @@ namespace smt {
void add_elim_string_axiom(expr* n);
void add_at_axiom(expr* n);
void add_in_re_axiom(expr* n);
bool add_stoi_axiom(expr* n);
bool add_itos_axiom(expr* n);
void add_itos_length_axiom(expr* n);
literal mk_literal(expr* n);