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Fix cleanup/initialization of sat::simplifier. Relates to #570.

This commit is contained in:
Christoph M. Wintersteiger 2016-11-09 18:00:15 +00:00
parent 6204f67d38
commit 890142ef96
6 changed files with 119 additions and 89 deletions

View file

@ -102,10 +102,14 @@ namespace sat {
unsigned m_val1;
unsigned m_val2;
public:
bin_clause(literal l1, literal l2, bool learned):m_val1(l1.to_uint()), m_val2((l2.to_uint() << 1) + static_cast<unsigned>(learned)) {}
bin_clause(literal l1, literal l2, bool learned) :m_val1(l1.to_uint()), m_val2((l2.to_uint() << 1) + static_cast<unsigned>(learned)) {}
literal get_literal1() const { return to_literal(m_val1); }
literal get_literal2() const { return to_literal(m_val2 >> 1); }
bool is_learned() const { return (m_val2 & 1) == 1; }
bool operator==(const bin_clause & other) const {
return m_val1 == other.m_val1 && m_val2 == other.m_val2 ||
m_val1 == other.m_val2 && m_val2 == other.m_val1;
}
};
class tmp_clause {

View file

@ -95,7 +95,7 @@ namespace sat {
if (updt_cache)
cache_bins(l, old_tr_sz);
s.pop(1);
literal_vector::iterator it = m_to_assert.begin();
literal_vector::iterator end = m_to_assert.end();
for (; it != end; ++it) {
@ -178,10 +178,10 @@ namespace sat {
m_num_assigned(p.m_num_assigned) {
m_watch.start();
}
~report() {
m_watch.stop();
IF_VERBOSE(SAT_VB_LVL,
IF_VERBOSE(SAT_VB_LVL,
verbose_stream() << " (sat-probing :probing-assigned "
<< (m_probing.m_num_assigned - m_num_assigned)
<< " :cost " << m_probing.m_counter;
@ -189,7 +189,7 @@ namespace sat {
verbose_stream() << mem_stat() << " :time " << std::fixed << std::setprecision(2) << m_watch.get_seconds() << ")\n";);
}
};
bool probing::operator()(bool force) {
if (!m_probing)
return true;
@ -200,8 +200,8 @@ namespace sat {
CASSERT("probing", s.check_invariant());
if (!force && m_counter > 0)
return true;
if (m_probing_cache && memory::get_allocation_size() > m_probing_cache_limit)
if (m_probing_cache && memory::get_allocation_size() > m_probing_cache_limit)
m_cached_bins.finalize();
report rpt(*this);
@ -256,14 +256,14 @@ namespace sat {
}
void probing::free_memory() {
m_assigned.cleanup();
m_assigned.finalize();
m_to_assert.finalize();
}
void probing::collect_statistics(statistics & st) const {
st.update("probing assigned", m_num_assigned);
}
void probing::reset_statistics() {
m_num_assigned = 0;
}

View file

@ -63,6 +63,7 @@ namespace sat {
}
simplifier::~simplifier() {
free_memory();
}
inline watch_list & simplifier::get_wlist(literal l) { return s.get_wlist(l); }
@ -96,7 +97,7 @@ namespace sat {
inline void simplifier::remove_clause_core(clause & c) {
unsigned sz = c.size();
for (unsigned i = 0; i < sz; i++)
insert_todo(c[i].var());
insert_elim_todo(c[i].var());
m_sub_todo.erase(c);
c.set_removed(true);
TRACE("resolution_bug", tout << "del_clause: " << c << "\n";);
@ -116,6 +117,7 @@ namespace sat {
inline void simplifier::remove_bin_clause_half(literal l1, literal l2, bool learned) {
SASSERT(s.get_wlist(~l1).contains(watched(l2, learned)));
s.get_wlist(~l1).erase(watched(l2, learned));
m_sub_bin_todo.erase(bin_clause(l1, l2, learned));
}
void simplifier::init_visited() {
@ -127,17 +129,33 @@ namespace sat {
m_use_list.finalize();
m_sub_todo.finalize();
m_sub_bin_todo.finalize();
m_elim_todo.finalize();
m_visited.finalize();
m_bs_cs.finalize();
m_bs_ls.finalize();
}
void simplifier::initialize() {
m_need_cleanup = false;
s.m_cleaner(true);
m_last_sub_trail_sz = s.m_trail.size();
m_use_list.init(s.num_vars());
m_sub_todo.reset();
m_sub_bin_todo.reset();
m_elim_todo.reset();
init_visited();
TRACE("after_cleanup", s.display(tout););
CASSERT("sat_solver", s.check_invariant());
}
void simplifier::operator()(bool learned) {
if (s.inconsistent())
return;
if (!m_subsumption && !m_elim_blocked_clauses && !m_resolution)
return;
initialize();
CASSERT("sat_solver", s.check_invariant());
TRACE("before_simplifier", s.display(tout););
@ -160,7 +178,6 @@ namespace sat {
if (!learned && (m_elim_blocked_clauses || m_elim_blocked_clauses_at == m_num_calls))
elim_blocked_clauses();
if (!learned)
m_num_calls++;
@ -619,7 +636,7 @@ namespace sat {
TRACE("elim_lit", tout << "processing: " << c << "\n";);
m_need_cleanup = true;
m_num_elim_lits++;
insert_todo(l.var());
insert_elim_todo(l.var());
c.elim(l);
clause_use_list & occurs = m_use_list.get(l);
occurs.erase_not_removed(c);
@ -922,7 +939,7 @@ namespace sat {
void process(literal l) {
TRACE("blocked_clause", tout << "processing: " << l << "\n";);
model_converter::entry * new_entry = 0;
if (s.is_external(l.var()) || s.was_eliminated(l.var()))
if (s.is_external(l.var()) || s.was_eliminated(l.var()))
return;
{
@ -1237,12 +1254,14 @@ namespace sat {
for (; it2 != end2; ++it2) {
if (it2->is_binary_clause() && it2->get_literal() == l) {
TRACE("bin_clause_bug", tout << "removing: " << l << " " << it2->get_literal() << "\n";);
m_sub_bin_todo.erase(bin_clause(l2, l, it2->is_learned()));
continue;
}
*itprev = *it2;
itprev++;
}
wlist2.set_end(itprev);
m_sub_bin_todo.erase(bin_clause(l, l2, it->is_learned()));
}
}
TRACE("bin_clause_bug", tout << "collapsing watch_list of: " << l << "\n";);
@ -1345,7 +1364,7 @@ namespace sat {
}
TRACE("resolution", tout << "found var to eliminate, before: " << before_clauses << " after: " << after_clauses << "\n";);
// eliminate variable
model_converter::entry & mc_entry = s.m_mc.mk(model_converter::ELIM_VAR, v);
save_clauses(mc_entry, m_pos_cls);

View file

@ -9,7 +9,7 @@ Abstract:
SAT simplification procedures that use a "full" occurrence list:
Subsumption, Blocked Clause Removal, Variable Elimination, ...
Author:
@ -83,7 +83,7 @@ namespace sat {
bool m_subsumption;
unsigned m_subsumption_limit;
bool m_elim_vars;
// stats
unsigned m_num_blocked_clauses;
unsigned m_num_subsumed;
@ -97,6 +97,8 @@ namespace sat {
void checkpoint();
void initialize();
void init_visited();
void mark_visited(literal l) { m_visited[l.index()] = true; }
void unmark_visited(literal l) { m_visited[l.index()] = false; }
@ -135,7 +137,7 @@ namespace sat {
void mark_as_not_learned_core(watch_list & wlist, literal l2);
void mark_as_not_learned(literal l1, literal l2);
void subsume();
void cleanup_watches();
void cleanup_clauses(clause_vector & cs, bool learned, bool vars_eliminated, bool in_use_lists);
@ -145,7 +147,7 @@ namespace sat {
lbool value(literal l) const;
watch_list & get_wlist(literal l);
watch_list const & get_wlist(literal l) const;
struct blocked_clause_elim;
void elim_blocked_clauses();
@ -172,14 +174,19 @@ namespace sat {
simplifier(solver & s, params_ref const & p);
~simplifier();
void insert_todo(bool_var v) { m_elim_todo.insert(v); }
void reset_todo() { m_elim_todo.reset(); }
void insert_elim_todo(bool_var v) { m_elim_todo.insert(v); }
void reset_todos() {
m_elim_todo.reset();
m_sub_todo.reset();
m_sub_bin_todo.reset();
}
void operator()(bool learned);
void updt_params(params_ref const & p);
static void collect_param_descrs(param_descrs & d);
void free_memory();
void collect_statistics(statistics & st) const;

View file

@ -141,7 +141,7 @@ namespace sat {
m_prev_phase.push_back(PHASE_NOT_AVAILABLE);
m_assigned_since_gc.push_back(false);
m_case_split_queue.mk_var_eh(v);
m_simplifier.insert_todo(v);
m_simplifier.insert_elim_todo(v);
SASSERT(!was_eliminated(v));
return v;
}
@ -151,7 +151,7 @@ namespace sat {
for (unsigned i = 0; i < num_lits; i++)
SASSERT(m_eliminated[lits[i].var()] == false);
});
if (m_user_scope_literals.empty()) {
mk_clause_core(num_lits, lits, false);
}
@ -175,8 +175,8 @@ namespace sat {
void solver::del_clause(clause& c) {
if (!c.is_learned()) m_stats.m_non_learned_generation++;
m_cls_allocator.del_clause(&c);
m_stats.m_del_clause++;
m_cls_allocator.del_clause(&c);
m_stats.m_del_clause++;
}
clause * solver::mk_clause_core(unsigned num_lits, literal * lits, bool learned) {
@ -188,7 +188,7 @@ namespace sat {
return 0; // clause is equivalent to true.
}
++m_stats.m_non_learned_generation;
}
}
switch (num_lits) {
case 0:
@ -739,10 +739,10 @@ namespace sat {
m_restart_threshold = m_config.m_restart_initial;
}
// iff3_finder(*this)();
// iff3_finder(*this)();
simplify_problem();
if (check_inconsistent()) return l_false;
if (m_config.m_max_conflicts == 0) {
IF_VERBOSE(SAT_VB_LVL, verbose_stream() << "(sat \"abort: max-conflicts = 0\")\n";);
@ -763,7 +763,7 @@ namespace sat {
restart();
simplify_problem();
if (check_inconsistent()) return l_false;
if (check_inconsistent()) return l_false;
gc();
}
}
@ -891,7 +891,7 @@ namespace sat {
else {
mk_model();
return l_true;
}
}
}
@ -920,8 +920,8 @@ namespace sat {
return;
}
TRACE("sat",
for (unsigned i = 0; i < num_lits; ++i)
TRACE("sat",
for (unsigned i = 0; i < num_lits; ++i)
tout << lits[i] << " ";
tout << "\n";
if (!m_user_scope_literals.empty()) {
@ -932,7 +932,7 @@ namespace sat {
for (unsigned i = 0; !inconsistent() && i < m_user_scope_literals.size(); ++i) {
literal nlit = ~m_user_scope_literals[i];
assign(nlit, justification());
assign(nlit, justification());
}
if (weights && !inconsistent()) {
@ -947,9 +947,9 @@ namespace sat {
for (unsigned i = 0; !inconsistent() && i < num_lits; ++i) {
literal lit = lits[i];
SASSERT(is_external(lit.var()));
add_assumption(lit);
assign(lit, justification());
SASSERT(is_external(lit.var()));
add_assumption(lit);
assign(lit, justification());
}
}
@ -962,10 +962,10 @@ namespace sat {
unsigned num_cores = 0;
for (unsigned i = 0; !inconsistent() && i < num_lits; ++i) {
literal lit = lits[i];
SASSERT(is_external(lit.var()));
SASSERT(is_external(lit.var()));
TRACE("sat", tout << "propagate: " << lit << " " << value(lit) << "\n";);
SASSERT(m_scope_lvl == 1);
add_assumption(lit);
add_assumption(lit);
switch(value(lit)) {
case l_undef:
values.push_back(l_true);
@ -973,10 +973,10 @@ namespace sat {
if (num_cores*2 >= num_lits) {
break;
}
propagate(false);
propagate(false);
if (inconsistent()) {
flet<bool> _init(m_initializing_preferred, true);
while (inconsistent()) {
while (inconsistent()) {
if (!resolve_conflict()) {
return true;
}
@ -1001,15 +1001,15 @@ namespace sat {
for (unsigned k = i; k >= j; --k) {
if (is_assumption(lits[k])) {
pop_assumption();
}
}
}
values.resize(j);
TRACE("sat", tout << "backjump " << (i - j + 1) << " steps " << num_cores << "\n";);
i = j - 1;
}
break;
case l_false:
break;
case l_false:
++num_cores;
values.push_back(l_false);
SASSERT(!inconsistent());
@ -1028,14 +1028,14 @@ namespace sat {
SASSERT(m_assumptions.size() <= i+1);
if (m_core.size() <= 3) {
m_inconsistent = true;
TRACE("opt", tout << "found small core: " << m_core << "\n";);
TRACE("opt", tout << "found small core: " << m_core << "\n";);
IF_VERBOSE(11, verbose_stream() << "(sat.core: " << m_core << ")\n";);
return true;
}
pop_assumption();
m_inconsistent = false;
m_inconsistent = false;
break;
case l_true:
case l_true:
values.push_back(l_true);
SASSERT(m_justification[lit.var()].get_kind() != justification::NONE || lvl(lit) == 0);
break;
@ -1046,7 +1046,7 @@ namespace sat {
if (m_weight >= max_weight) {
// block the current correction set candidate.
++m_stats.m_blocked_corr_sets;
TRACE("opt", tout << "blocking soft correction set: " << m_blocker << "\n";);
TRACE("opt", tout << "blocking soft correction set: " << m_blocker << "\n";);
IF_VERBOSE(11, verbose_stream() << "blocking " << m_blocker << "\n";);
pop_to_base_level();
mk_clause_core(m_blocker);
@ -1062,17 +1062,17 @@ namespace sat {
m_min_core.reset();
m_min_core.append(m_core);
m_min_core_valid = true;
}
}
}
void solver::reset_assumptions() {
m_assumptions.reset();
m_assumption_set.reset();
m_assumption_set.reset();
}
void solver::add_assumption(literal lit) {
m_assumption_set.insert(lit);
m_assumptions.push_back(lit);
m_assumption_set.insert(lit);
m_assumptions.push_back(lit);
}
void solver::pop_assumption() {
@ -1089,8 +1089,8 @@ namespace sat {
for (unsigned i = 0; i < m_min_core.size(); ++i) {
literal lit = m_min_core[i];
SASSERT(is_external(lit.var()));
add_assumption(lit);
assign(lit, justification());
add_assumption(lit);
assign(lit, justification());
}
propagate(false);
SASSERT(inconsistent());
@ -1132,7 +1132,7 @@ namespace sat {
m_min_core_valid = false;
m_min_core.reset();
TRACE("sat", display(tout););
if (m_config.m_bcd) {
bceq bc(*this);
bc();
@ -1149,11 +1149,11 @@ namespace sat {
}
IF_VERBOSE(2, verbose_stream() << "(sat.simplify)\n";);
// Disable simplification during MUS computation.
// Disable simplification during MUS computation.
// if (m_mus.is_active()) return;
TRACE("sat", tout << "simplify\n";);
pop(scope_lvl());
pop(scope_lvl());
SASSERT(scope_lvl() == 0);
@ -1166,7 +1166,7 @@ namespace sat {
m_simplifier(false);
CASSERT("sat_simplify_bug", check_invariant());
CASSERT("sat_missed_prop", check_missed_propagation());
if (!m_learned.empty()) {
m_simplifier(true);
CASSERT("sat_missed_prop", check_missed_propagation());
@ -1260,7 +1260,7 @@ namespace sat {
TRACE("sat", tout << "failed: " << c << "\n";
tout << "assumptions: " << m_assumptions << "\n";
tout << "trail: " << m_trail << "\n";
tout << "model: " << m << "\n";
tout << "model: " << m << "\n";
m_mc.display(tout);
);
ok = false;
@ -1289,10 +1289,10 @@ namespace sat {
}
for (unsigned i = 0; i < m_assumptions.size(); ++i) {
if (value_at(m_assumptions[i], m) != l_true) {
TRACE("sat",
TRACE("sat",
tout << m_assumptions[i] << " does not model check\n";
tout << "trail: " << m_trail << "\n";
tout << "model: " << m << "\n";
tout << "model: " << m << "\n";
m_mc.display(tout);
);
ok = false;
@ -1664,7 +1664,7 @@ namespace sat {
resolve_conflict_for_unsat_core();
return false;
}
if (m_conflict_lvl == 0) {
return false;
}
@ -1849,11 +1849,11 @@ namespace sat {
bool solver::resolve_conflict_for_init() {
if (m_conflict_lvl == 0) {
return false;
}
}
m_lemma.reset();
m_lemma.push_back(null_literal); // asserted literal
if (m_not_l != null_literal) {
TRACE("sat", tout << "not_l: " << m_not_l << "\n";);
TRACE("sat", tout << "not_l: " << m_not_l << "\n";);
process_antecedent_for_init(m_not_l);
}
literal consequent = m_not_l;
@ -1988,7 +1988,7 @@ namespace sat {
SASSERT(!is_marked(m_trail[i].var()));
}});
unsigned old_size = m_unmark.size();
unsigned old_size = m_unmark.size();
int idx = skip_literals_above_conflict_level();
if (m_not_l != null_literal) {
@ -2005,7 +2005,7 @@ namespace sat {
process_consequent_for_unsat_core(m_not_l, js);
}
}
literal consequent = m_not_l;
justification js = m_conflict;
@ -2031,7 +2031,7 @@ namespace sat {
SASSERT(lvl(consequent) == m_conflict_lvl);
js = m_justification[c_var];
idx--;
}
}
reset_unmark(old_size);
if (m_config.m_core_minimize) {
if (m_min_core_valid && m_min_core.size() < m_core.size()) {
@ -2039,7 +2039,7 @@ namespace sat {
m_core.reset();
m_core.append(m_min_core);
}
// TBD:
// TBD:
// apply optional clause minimization by detecting subsumed literals.
// initial experiment suggests it has no effect.
m_mus(); // ignore return value on cancelation.
@ -2511,7 +2511,7 @@ namespace sat {
void solver::pop_reinit(unsigned num_scopes) {
pop(num_scopes);
reinit_assumptions();
reinit_assumptions();
}
void solver::pop(unsigned num_scopes) {
@ -2578,13 +2578,13 @@ namespace sat {
m_clauses_to_reinit.shrink(j);
}
//
//
// All new clauses that are added to the solver
// are relative to the user-scope literals.
//
//
void solver::user_push() {
literal lit;
literal lit;
bool_var new_v = mk_var(true, false);
lit = literal(new_v, false);
m_user_scope_literals.push_back(lit);
@ -2674,7 +2674,7 @@ namespace sat {
m_phase.shrink(v);
m_prev_phase.shrink(v);
m_assigned_since_gc.shrink(v);
m_simplifier.reset_todo();
m_simplifier.reset_todos();
}
}
@ -2698,7 +2698,7 @@ namespace sat {
unassign_vars(i);
break;
}
}
}
gc_var(lit.var());
}
}
@ -3084,10 +3084,10 @@ namespace sat {
}
bool non_empty = true;
m_seen[0].reset();
while (non_empty) {
while (non_empty) {
literal_vector mutex;
bool turn = false;
m_reachable[turn] = ps;
m_reachable[turn] = ps;
while (!m_reachable[turn].empty()) {
literal p = m_reachable[turn].pop();
if (m_seen[0].contains(p)) {
@ -3104,7 +3104,7 @@ namespace sat {
turn = !turn;
}
if (mutex.size() > 1) {
mutexes.push_back(mutex);
mutexes.push_back(mutex);
}
non_empty = !mutex.empty();
}
@ -3148,7 +3148,7 @@ namespace sat {
switch (get_model()[v]) {
case l_true: lits.push_back(literal(v, false)); break;
case l_false: lits.push_back(literal(v, true)); break;
default: break;
default: break;
}
}
is_sat = get_consequences(asms, lits, conseq);
@ -3175,7 +3175,7 @@ namespace sat {
}
propagate(false);
if (check_inconsistent()) return l_false;
unsigned num_units = 0, num_iterations = 0;
extract_fixed_consequences(num_units, assumptions, vars, conseq);
while (!vars.empty()) {
@ -3192,14 +3192,14 @@ namespace sat {
push();
assign(~lit, justification());
propagate(false);
while (inconsistent()) {
while (inconsistent()) {
if (!resolve_conflict()) {
TRACE("sat", display(tout << "inconsistent\n"););
m_inconsistent = false;
is_sat = l_undef;
break;
}
propagate(false);
propagate(false);
++num_resolves;
}
if (scope_lvl() == 1) {
@ -3213,7 +3213,7 @@ namespace sat {
else {
is_sat = bounded_search();
if (is_sat == l_undef) {
restart();
restart();
}
}
}
@ -3224,7 +3224,7 @@ namespace sat {
if (is_sat == l_true) {
delete_unfixed(vars);
}
extract_fixed_consequences(num_units, assumptions, vars, conseq);
extract_fixed_consequences(num_units, assumptions, vars, conseq);
IF_VERBOSE(1, verbose_stream() << "(sat.get-consequences"
<< " iterations: " << num_iterations
<< " variables: " << vars.size()
@ -3244,10 +3244,10 @@ namespace sat {
if (value(lit) == l_true) {
to_keep.insert(lit);
}
}
}
unfixed = to_keep;
}
void solver::extract_fixed_consequences(unsigned& start, literal_set const& assumptions, literal_set& unfixed, vector<literal_vector>& conseq) {
if (scope_lvl() > 1) {
pop(scope_lvl() - 1);
@ -3297,7 +3297,7 @@ namespace sat {
}
void solver::extract_fixed_consequences(literal lit, literal_set const& assumptions, literal_set& unfixed, vector<literal_vector>& conseq) {
index_set s;
index_set s;
if (assumptions.contains(lit)) {
s.insert(lit.index());
}

View file

@ -200,7 +200,7 @@ namespace sat {
iterator begin() const { return m_set.begin(); }
iterator end() const { return m_set.end(); }
void reset() { m_set.reset(); m_in_set.reset(); }
void cleanup() { m_set.finalize(); m_in_set.finalize(); }
void finalize() { m_set.finalize(); m_in_set.finalize(); }
uint_set& operator&=(uint_set const& other) {
unsigned j = 0;
for (unsigned i = 0; i < m_set.size(); ++i) {
@ -259,7 +259,7 @@ namespace sat {
bool empty() const { return m_set.empty(); }
unsigned size() const { return m_set.size(); }
void reset() { m_set.reset(); }
void cleanup() { m_set.cleanup(); }
void finalize() { m_set.finalize(); }
class iterator {
uint_set::iterator m_it;
public: