mirrors/z3
3
0
Fork 0
mirror of https://github.com/Z3Prover/z3 synced 2025-05-11 09:44:43 +00:00
Code Activity

z3str3: add smt.str.fixed_length_naive_cex option for naive length-based counterexamples

Browse source
This commit is contained in:
Murphy Berzish 2020-01-20 15:34:43 -05:00 • committed by Nikolaj Bjorner
parent c1e7d7788e
commit cf3f271f5b
4 changed files with 39 additions and 21 deletions
Download patch file Download diff file Expand all files Collapse all files

47
src/smt/theory_str_mc.cpp
View file

@ -875,29 +875,36 @@ namespace smt {
return l_true;
} else if (subproblem_status == l_false) {
// TODO replace this with something simpler for now
NOT_IMPLEMENTED_YET();
TRACE("str_fl", tout << "subsolver found UNSAT; reconstructing unsat core" << std::endl;);
TRACE("str_fl", tout << "unsat core has size " << subsolver.get_unsat_core_size() << std::endl;);
bool negate_pre = false;
for (unsigned i = 0; i < subsolver.get_unsat_core_size(); ++i) {
TRACE("str", tout << "entry " << i << " = " << mk_pp(subsolver.get_unsat_core_expr(i), m) << std::endl;);
rational index;
expr* lhs;
expr* rhs;
std::tie(index, lhs, rhs) = fixed_length_lesson.find(subsolver.get_unsat_core_expr(i));
TRACE("str_fl", tout << "lesson: " << mk_pp(lhs, m) << " == " << mk_pp(rhs, m) << " at index " << index << std::endl;);
cex.push_back(refine(lhs, rhs, index));
if (index < rational(0)) {
negate_pre = true;
if (m_params.m_FixedLengthNaiveCounterexamples) {
TRACE("str_fl", tout << "subsolver found UNSAT; constructing length counterexample" << std::endl;);
for (auto e : fixed_length_used_len_terms) {
expr * var = &e.get_key();
cex.push_back(m.mk_eq(u.str.mk_length(var), mk_int(e.get_value())));
}
}
if (negate_pre){
for (auto ex : precondition) {
cex.push_back(ex);
return l_false;
} else {
TRACE("str_fl", tout << "subsolver found UNSAT; reconstructing unsat core" << std::endl;);
TRACE("str_fl", tout << "unsat core has size " << subsolver.get_unsat_core_size() << std::endl;);
bool negate_pre = false;
for (unsigned i = 0; i < subsolver.get_unsat_core_size(); ++i) {
TRACE("str", tout << "entry " << i << " = " << mk_pp(subsolver.get_unsat_core_expr(i), m) << std::endl;);
rational index;
expr* lhs;
expr* rhs;
std::tie(index, lhs, rhs) = fixed_length_lesson.find(subsolver.get_unsat_core_expr(i));
TRACE("str_fl", tout << "lesson: " << mk_pp(lhs, m) << " == " << mk_pp(rhs, m) << " at index " << index << std::endl;);
cex.push_back(refine(lhs, rhs, index));
if (index < rational(0)) {
negate_pre = true;
}
}
if (negate_pre){
for (auto ex : precondition) {
cex.push_back(ex);
}
}
return l_false;
}
return l_false;
} else { // l_undef
TRACE("str_fl", tout << "WARNING: subsolver found UNKNOWN" << std::endl;);
return l_undef;