mirrors/z3
3
0
Fork 0
mirror of https://github.com/Z3Prover/z3 synced 2025-05-07 07:45:46 +00:00
Code Activity

removing unit clauses and dependency manager, use minisat approach by tracking assumption literals directly also in clauses

Browse source 
Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>
This commit is contained in:
Nikolaj Bjorner 2021-09-20 15:10:03 -07:00
parent bb5ff8db24
commit 8ee54c665a
12 changed files with 60 additions and 179 deletions
Download patch file Download diff file Expand all files Collapse all files

35
src/math/polysat/constraint.cpp
View file

@ -56,39 +56,12 @@ namespace polysat {
}
void constraint_manager::store(clause* cl, solver& s) {
while (m_clauses.size() <= cl->level())
while (m_clauses.size() <= s.base_level())
m_clauses.push_back({});
m_clauses[cl->level()].push_back(cl);
m_clauses[s.base_level()].push_back(cl);
watch(*cl, s);
}
void constraint_manager::register_external(signed_constraint c) {
SASSERT(c);
SASSERT(!c->is_external());
if (c->unit_dep() && c->unit_dep()->is_leaf()) {
unsigned const dep = c->unit_dep()->leaf_value();
SASSERT(!m_external_constraints.contains(dep));
m_external_constraints.insert(dep, c.get());
}
c->set_external(c.is_negative());
++m_num_external;
}
void constraint_manager::unregister_external(constraint* c) {
if (c->unit_dep() && c->unit_dep()->is_leaf())
m_external_constraints.remove(c->unit_dep()->leaf_value());
c->unset_external();
--m_num_external;
}
signed_constraint constraint_manager::lookup_external(unsigned dep) const {
constraint* c = m_external_constraints.get(dep, nullptr);
if (c)
return {c, !c->external_sign()};
else
return {};
}
// Release constraints at the given level and above.
void constraint_manager::release_level(unsigned lvl) {
for (unsigned l = m_clauses.size(); l-- > lvl; ) {
@ -292,14 +265,14 @@ namespace polysat {
void constraint::set_unit_clause(clause *cl) {
// can be seen as a cache... store the lowest-level unit clause for this constraint.
if (!cl || !m_unit_clause || m_unit_clause->level() > cl->level())
if (!cl || !m_unit_clause)
m_unit_clause = cl;
}
unsigned constraint::level(solver& s) const {
if (s.m_bvars.value(sat::literal(bvar())) != l_undef)
return s.m_bvars.level(bvar());
unsigned level = 0;
unsigned level = s.base_level();
for (auto v : vars())
if (s.is_assigned(v))
level = std::max(level, s.get_level(v));