3
0
Fork 0
mirror of https://github.com/Z3Prover/z3 synced 2025-04-24 01:25:31 +00:00

fixes top lookahead simplification

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>
This commit is contained in:
Nikolaj Bjorner 2017-06-21 20:22:31 -07:00
parent 5f93b9a081
commit 5e2f7f7177
4 changed files with 23 additions and 19 deletions

View file

@ -841,6 +841,7 @@ namespace sat {
unsigned sz = m_s.m_watches.size();
for (unsigned l_idx = 0; l_idx < sz; ++l_idx) {
literal l = ~to_literal(l_idx);
if (m_s.was_eliminated(l.var())) continue;
watch_list const & wlist = m_s.m_watches[l_idx];
watch_list::const_iterator it = wlist.begin();
watch_list::const_iterator end = wlist.end();
@ -848,9 +849,7 @@ namespace sat {
if (!it->is_binary_non_learned_clause())
continue;
literal l2 = it->get_literal();
SASSERT(!m_s.was_eliminated(l.var()));
SASSERT(!m_s.was_eliminated(l2.var()));
if (l.index() < l2.index())
if (l.index() < l2.index() && !m_s.was_eliminated(l2.var()))
add_binary(l, l2);
}
}
@ -895,6 +894,12 @@ namespace sat {
m_config.m_use_ternary_reward = false;
}
#endif
bool was_eliminated = false;
for (unsigned i = 0; !was_eliminated && i < c.size(); ++i) {
was_eliminated = m_s.was_eliminated(c[i].var());
}
if (was_eliminated) continue;
clause* c1 = m_cls_allocator.mk_clause(c.size(), c.begin(), false);
m_clauses.push_back(c1);
attach_clause(*c1);
@ -1519,7 +1524,9 @@ namespace sat {
if (m_search_mode == lookahead_mode::searching) {
m_stats.m_propagations++;
TRACE("sat", tout << "removing free var v" << l.var() << "\n";);
m_freevars.remove(l.var());
if (l.var() > m_freevars.max_var()) std::cout << "bigger than max-var: " << l << " " << " " << m_freevars.max_var() << "\n";
if (!m_freevars.contains(l.var())) std::cout << "does not contain: " << l << " eliminated: " << m_s.was_eliminated(l.var()) << "\n";
if (m_freevars.contains(l.var())) { m_freevars.remove(l.var()); }
validate_assign(l);
}
}
@ -1722,16 +1729,20 @@ namespace sat {
if (inconsistent()) return;
SASSERT(m_trail_lim.empty());
unsigned num_units = 0;
for (unsigned i = 0; i < m_trail.size(); ++i) {
for (unsigned i = 0; i < m_trail.size() && !m_s.inconsistent(); ++i) {
literal lit = m_trail[i];
if (m_s.value(lit) == l_undef && !m_s.was_eliminated(lit.var())) {
m_s.m_simplifier.propagate_unit(lit);
m_s.assign(lit, justification());
++num_units;
}
}
}
IF_VERBOSE(1, verbose_stream() << "(sat-lookahead :units " << num_units << ")\n";);
m_s.m_simplifier.subsume();
if (num_units > 0 && !m_s.inconsistent()) {
m_s.propagate_core(false);
m_s.m_simplifier(false);
}
m_lookahead.reset();
}

View file

@ -166,10 +166,7 @@ namespace sat {
CASSERT("sat_solver", s.check_invariant());
TRACE("before_simplifier", s.display(tout););
m_sub_todo.reset();
m_sub_bin_todo.reset();
s.m_cleaner(true);
m_last_sub_trail_sz = s.m_trail.size();
TRACE("after_cleanup", s.display(tout););
CASSERT("sat_solver", s.check_invariant());
m_need_cleanup = false;
@ -223,13 +220,6 @@ namespace sat {
}
}
if (!learned && s.m_config.m_lookahead_simplify) {
// perform lookahead simplification
lookahead lh(s);
lh.simplify();
lh.collect_statistics(s.m_aux_stats);
}
CASSERT("sat_solver", s.check_invariant());
TRACE("after_simplifier", s.display(tout); tout << "model_converter:\n"; s.m_mc.display(tout););

View file

@ -1355,6 +1355,7 @@ namespace sat {
m_luby_idx = 1;
m_gc_threshold = m_config.m_gc_initial;
m_restarts = 0;
m_conflicts = 0;
m_min_d_tk = 1.0;
m_search_lvl = 0;
m_stopwatch.reset();
@ -1399,6 +1400,7 @@ namespace sat {
if (m_config.m_lookahead_simplify) {
lookahead lh(*this);
lh.simplify();
lh.scc();
lh.collect_statistics(m_aux_stats);
}