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Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>
This commit is contained in:
Nikolaj Bjorner 2017-04-19 08:59:49 -07:00
parent a3f4d58b00
commit e65f106a83
13 changed files with 573 additions and 32 deletions

View file

@ -3,6 +3,7 @@ z3_add_component(sat
card_extension.cpp
dimacs.cpp
sat_asymm_branch.cpp
sat_ccc.cpp
sat_clause.cpp
sat_clause_set.cpp
sat_clause_use_list.cpp

View file

@ -26,8 +26,7 @@ namespace sat {
m_index(index),
m_lit(lit),
m_k(k),
m_size(lits.size())
{
m_size(lits.size()) {
for (unsigned i = 0; i < lits.size(); ++i) {
m_lits[i] = lits[i];
}
@ -42,6 +41,27 @@ namespace sat {
SASSERT(m_size >= m_k && m_k > 0);
}
card_extension::pb::pb(unsigned index, literal lit, svector<card_extension::wliteral> const& wlits, unsigned k):
m_index(index),
m_lit(lit),
m_k(k),
m_size(wlits.size()) {
for (unsigned i = 0; i < wlits.size(); ++i) {
m_wlits[i] = wlits[i];
}
}
void card_extension::pb::negate() {
m_lit.neg();
unsigned w = 0;
for (unsigned i = 0; i < m_size; ++i) {
m_wlits[i].second.neg();
w += m_wlits[i].first;
}
m_k = w - m_k + 1;
SASSERT(w >= m_k && m_k > 0);
}
card_extension::xor::xor(unsigned index, literal lit, literal_vector const& lits):
m_index(index),
m_lit(lit),
@ -191,6 +211,15 @@ namespace sat {
SASSERT(s().inconsistent());
}
// pb:
void card_extension::init_watch(pb& p, bool is_true) {
NOT_IMPLEMENTED_YET();
}
// xor:
void card_extension::clear_watch(xor& x) {
unwatch_literal(x[0], &x);
unwatch_literal(x[1], &x);
@ -510,7 +539,7 @@ namespace sat {
process_card(c, offset);
++m_stats.m_num_card_resolves;
}
else {
else if (is_xor_index(index)) {
// jus.push_back(js);
m_lemma.reset();
m_bound += offset;
@ -521,6 +550,12 @@ namespace sat {
}
++m_stats.m_num_xor_resolves;
}
else if (is_pb_index(index)) {
NOT_IMPLEMENTED_YET();
}
else {
UNREACHABLE();
}
break;
}
default:
@ -758,7 +793,7 @@ namespace sat {
}
void card_extension::add_at_least(bool_var v, literal_vector const& lits, unsigned k) {
unsigned index = 2*m_cards.size();
unsigned index = 4*m_cards.size();
literal lit = v == null_bool_var ? null_literal : literal(v, false);
card* c = new (memory::allocate(card::get_obj_size(lits.size()))) card(index, lit, lits, k);
m_cards.push_back(c);
@ -774,9 +809,26 @@ namespace sat {
}
}
void card_extension::add_pb_ge(bool_var v, svector<wliteral> const& wlits, unsigned k) {
unsigned index = 4*m_pb.size() + 0x11;
literal lit = v == null_bool_var ? null_literal : literal(v, false);
pb* p = new (memory::allocate(pb::get_obj_size(wlits.size()))) pb(index, lit, wlits, k);
m_pb.push_back(p);
if (v == null_bool_var) {
init_watch(*p, true);
m_pb_axioms.push_back(p);
}
else {
init_watch(v);
m_var_infos[v].m_pb = p;
m_var_trail.push_back(v);
}
}
void card_extension::add_xor(bool_var v, literal_vector const& lits) {
m_has_xor = true;
unsigned index = 2*m_xors.size()+1;
unsigned index = 4*m_xors.size() + 0x01;
xor* x = new (memory::allocate(xor::get_obj_size(lits.size()))) xor(index, literal(v, false), lits);
m_xors.push_back(x);
init_watch(v);
@ -819,7 +871,7 @@ namespace sat {
unsigned level = lvl(l);
bool_var v = l.var();
SASSERT(js.get_kind() == justification::EXT_JUSTIFICATION);
SASSERT(!is_card_index(js.get_ext_justification_idx()));
SASSERT(is_xor_index(js.get_ext_justification_idx()));
TRACE("sat", tout << l << ": " << js << "\n"; tout << s().m_trail << "\n";);
unsigned num_marks = 0;
@ -828,7 +880,7 @@ namespace sat {
++count;
if (js.get_kind() == justification::EXT_JUSTIFICATION) {
unsigned idx = js.get_ext_justification_idx();
if (is_card_index(idx)) {
if (!is_xor_index(idx)) {
r.push_back(l);
}
else {
@ -912,7 +964,7 @@ namespace sat {
r.push_back(~c[i]);
}
}
else {
else if (is_xor_index(idx)) {
xor& x = index2xor(idx);
if (x.lit() != null_literal) r.push_back(x.lit());
TRACE("sat", display(tout << l << " ", x, true););
@ -931,6 +983,12 @@ namespace sat {
r.push_back(value(x[i]) == l_true ? x[i] : ~x[i]);
}
}
else if (is_pb_index(idx)) {
NOT_IMPLEMENTED_YET();
}
else {
UNREACHABLE();
}
}
@ -1281,13 +1339,19 @@ namespace sat {
}
out << ">= " << c.k();
}
else {
else if (is_xor_index(idx)) {
xor& x = index2xor(idx);
out << "xor " << x.lit() << ": ";
for (unsigned i = 0; i < x.size(); ++i) {
out << x[i] << " ";
}
}
else if (is_pb_index(idx)) {
NOT_IMPLEMENTED_YET();
}
else {
UNREACHABLE();
}
return out;
}
@ -1382,7 +1446,7 @@ namespace sat {
}
if (c.lit() != null_literal) p.push(~c.lit(), offset*c.k());
}
else {
else if (is_xor_index(index)) {
literal_vector ls;
get_antecedents(lit, index, ls);
p.reset(offset);
@ -1392,6 +1456,12 @@ namespace sat {
literal lxor = index2xor(index).lit();
if (lxor != null_literal) p.push(~lxor, offset);
}
else if (is_pb_index(index)) {
NOT_IMPLEMENTED_YET();
}
else {
UNREACHABLE();
}
break;
}
default:

View file

@ -58,6 +58,26 @@ namespace sat {
void swap(unsigned i, unsigned j) { std::swap(m_lits[i], m_lits[j]); }
void negate();
};
typedef std::pair<unsigned, literal> wliteral;
class pb {
unsigned m_index;
literal m_lit;
unsigned m_k;
unsigned m_size;
wliteral m_wlits[0];
public:
static size_t get_obj_size(unsigned num_lits) { return sizeof(card) + num_lits * sizeof(wliteral); }
pb(unsigned index, literal lit, svector<wliteral> const& wlits, unsigned k);
unsigned index() const { return m_index; }
literal lit() const { return m_lit; }
wliteral operator[](unsigned i) const { return m_wlits[i]; }
unsigned k() const { return m_k; }
unsigned size() const { return m_size; }
void swap(unsigned i, unsigned j) { std::swap(m_wlits[i], m_wlits[j]); }
void negate();
};
class xor {
unsigned m_index;
@ -85,20 +105,28 @@ namespace sat {
typedef ptr_vector<card> card_watch;
typedef ptr_vector<xor> xor_watch;
typedef ptr_vector<pb> pb_watch;
struct var_info {
card_watch* m_card_watch[2];
pb_watch* m_pb_watch[2];
xor_watch* m_xor_watch;
card* m_card;
pb* m_pb;
xor* m_xor;
var_info(): m_xor_watch(0), m_card(0), m_xor(0) {
var_info(): m_xor_watch(0), m_card(0), m_xor(0), m_pb(0) {
m_card_watch[0] = 0;
m_card_watch[1] = 0;
m_pb_watch[0] = 0;
m_pb_watch[1] = 0;
}
void reset() {
dealloc(m_card);
dealloc(m_xor);
dealloc(m_pb);
dealloc(card_extension::set_tag_non_empty(m_card_watch[0]));
dealloc(card_extension::set_tag_non_empty(m_card_watch[1]));
dealloc(card_extension::set_tag_non_empty(m_pb_watch[0]));
dealloc(card_extension::set_tag_non_empty(m_pb_watch[1]));
dealloc(card_extension::set_tag_non_empty(m_xor_watch));
}
};
@ -125,8 +153,10 @@ namespace sat {
ptr_vector<card> m_cards;
ptr_vector<xor> m_xors;
ptr_vector<pb> m_pb;
scoped_ptr_vector<card> m_card_axioms;
scoped_ptr_vector<pb> m_pb_axioms;
// watch literals
svector<var_info> m_var_infos;
@ -173,11 +203,17 @@ namespace sat {
lbool add_assign(xor& x, literal alit);
void asserted_xor(literal l, ptr_vector<xor>* xors, xor* x);
bool is_card_index(unsigned idx) const { return 0 == (idx & 0x1); }
card& index2card(unsigned idx) const { SASSERT(is_card_index(idx)); return *m_cards[idx >> 1]; }
xor& index2xor(unsigned idx) const { SASSERT(!is_card_index(idx)); return *m_xors[idx >> 1]; }
bool is_card_index(unsigned idx) const { return 0x00 == (idx & 0x11); }
bool is_xor_index(unsigned idx) const { return 0x01 == (idx & 0x11); }
bool is_pb_index(unsigned idx) const { return 0x11 == (idx & 0x11); }
card& index2card(unsigned idx) const { SASSERT(is_card_index(idx)); return *m_cards[idx >> 2]; }
xor& index2xor(unsigned idx) const { SASSERT(!is_card_index(idx)); return *m_xors[idx >> 2]; }
pb& index2pb(unsigned idx) const { SASSERT(is_pb_index(idx)); return *m_pb[idx >> 2]; }
void get_xor_antecedents(literal l, unsigned inddex, justification js, literal_vector& r);
void init_watch(pb& p, bool is_true);
template<typename T>
bool remove(ptr_vector<T>& ts, T* t) {
@ -233,6 +269,7 @@ namespace sat {
virtual ~card_extension();
virtual void set_solver(solver* s) { m_solver = s; }
void add_at_least(bool_var v, literal_vector const& lits, unsigned k);
void add_pb_ge(bool_var v, svector<wliteral> const& wlits, unsigned k);
void add_xor(bool_var v, literal_vector const& lits);
virtual void propagate(literal l, ext_constraint_idx idx, bool & keep);
virtual bool resolve_conflict();

271
src/sat/sat_ccc.cpp Normal file
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@ -0,0 +1,271 @@
/*++
Copyright (c) 2017 Microsoft Corporation
Module Name:
sat_ccc.cpp
Abstract:
A variant of Concurrent Cube and Conquer
Author:
Nikolaj Bjorner (nbjorner) 2017-4-17
Notes:
--*/
#include "sat_solver.h"
#include "sat_lookahead.h"
#include "sat_ccc.h"
using namespace sat;
lbool ccc::cube() {
unsigned branch_id = 0;
unsigned_vector id_trail;
lookahead lh(s);
lh.init_search();
lh.m_model.reset();
lookahead::scoped_level _sl(lh, lh.c_fixed_truth);
literal_vector trail;
lh.m_search_mode = lookahead_mode::searching;
while (!m_cancel) {
// remove old branch ids from id_trail.
while (id_trail.size() > trail.size()) {
id_trail.pop_back();
}
TRACE("sat", lh.display(tout););
lh.inc_istamp();
s.checkpoint();
if (lh.inconsistent()) {
if (!lh.backtrack(trail)) return l_false;
continue;
}
// check if CDCL solver got ahead.
bool repeat = false;
#pragma omp critical (ccc_solved)
{
if (!m_solved.empty()) {
unsigned solved_id = m_solved.top();
if (id_trail.contains(solved_id)) {
lh.set_conflict();
}
else {
m_solved.pop();
}
repeat = true;
}
}
if (repeat) continue;
++branch_id;
if (!trail.empty()) {
#pragma omp critical (ccc_decisions)
{
m_decisions.push(decision(branch_id, trail.size()-1, trail.back()));
}
}
literal l = lh.choose();
if (lh.inconsistent()) {
if (!lh.backtrack(trail)) return l_false;
continue;
}
if (l == null_literal) {
m_model = lh.get_model();
return l_true;
}
// update trail and set of ids
id_trail.push_back(branch_id);
trail.push_back(l);
SASSERT(id_trail.size() == trail.size());
TRACE("sat", tout << "choose: " << l << " " << trail << "\n";);
++lh.m_stats.m_decisions;
IF_VERBOSE(1, verbose_stream() << "select " << pp_prefix(lh.m_prefix, lh.m_trail_lim.size()) << ": " << l << " " << lh.m_trail.size() << "\n";);
lh.push(l, lh.c_fixed_truth);
SASSERT(lh.inconsistent() || !lh.is_unsat());
}
return l_undef;
}
lbool ccc::conquer(solver& s) {
try {
if (s.inconsistent()) return l_false;
s.init_search();
s.propagate(false);
if (s.inconsistent()) return l_false;
s.init_assumptions(0, 0);
s.propagate(false);
if (s.check_inconsistent()) return l_false;
s.cleanup();
s.simplify_problem();
if (s.check_inconsistent()) return l_false;
unsigned_vector ids;
while (true) {
SASSERT(!s.inconsistent());
lbool r = bounded_search(s, ids);
if (r != l_undef)
return r;
if (s.m_conflicts > s.m_config.m_max_conflicts) {
IF_VERBOSE(SAT_VB_LVL, verbose_stream() << "(sat \"abort: max-conflicts = " << s.m_conflicts << "\")\n";);
return l_undef;
}
s.restart();
s.simplify_problem();
if (s.check_inconsistent()) return l_false;
s.gc();
}
}
catch (solver::abort_solver) {
return l_undef;
}
}
lbool ccc::bounded_search(solver& s, unsigned_vector& ids) {
decision d;
while (true) {
s.checkpoint();
bool done = false;
while (!done) {
lbool is_sat = s.propagate_and_backjump_step(done);
if (is_sat != l_true) return is_sat;
}
if (s.m_scope_lvl < ids.size()) {
while (ids.size() > s.m_scope_lvl + 1) ids.pop_back();
unsigned id = ids.back();
ids.pop_back();
#pragma omp critical (ccc_solved)
{
m_solved.push(id);
}
}
s.gc();
bool cube_decision = false;
#pragma omp critical (ccc_decisions)
{
if (!m_decisions.empty()) {
d = m_decisions.pop();
cube_decision = true;
}
}
if (cube_decision) {
if (d.m_depth > ids.size()) continue;
ids.push_back(d.m_id);
s.pop_reinit(s.m_scope_lvl - d.m_depth); // TBD: check alignment of scopes
s.push();
s.assign(d.m_last, justification());
}
else if (!s.decide()) {
lbool is_sat = s.final_check();
if (is_sat != l_undef) {
return is_sat;
}
}
}
}
lbool ccc::search() {
enum par_exception_kind {
DEFAULT_EX,
ERROR_EX
};
m_cancel = false;
scoped_limits scoped_rlimit(s.rlimit());
vector<reslimit> limits;
ptr_vector<solver> solvers;
int finished_id = -1;
std::string ex_msg;
par_exception_kind ex_kind;
unsigned error_code = 0;
lbool result = l_undef;
bool canceled = false;
int num_threads = s.m_config.m_num_threads + 1;
for (int i = 1; i < num_threads; ++i) {
limits.push_back(reslimit());
}
for (int i = 1; i < num_threads; ++i) {
s.m_params.set_uint("random_seed", s.m_rand());
solvers[i] = alloc(sat::solver, s.m_params, limits[i]);
solvers[i]->copy(s);
scoped_rlimit.push_child(&solvers[i]->rlimit());
}
#pragma omp parallel for
for (int i = 0; i < num_threads; ++i) {
try {
lbool r = l_undef;
if (i == 0) {
r = cube();
}
else {
r = conquer(*solvers[i-1]);
}
bool first = false;
#pragma omp critical (par_solver)
{
if (finished_id == -1) {
finished_id = i;
first = true;
result = r;
}
}
if (first) {
for (unsigned j = 0; j < solvers.size(); ++j) {
solvers[j]->rlimit().cancel();
}
// cancel lookahead solver:
m_cancel = true;
}
}
catch (z3_error & err) {
error_code = err.error_code();
ex_kind = ERROR_EX;
}
catch (z3_exception & ex) {
ex_msg = ex.msg();
ex_kind = DEFAULT_EX;
}
}
if (finished_id > 0 && result == l_true) {
// set model from auxiliary solver
m_model = solvers[finished_id - 1]->get_model();
}
for (unsigned i = 0; i < solvers.size(); ++i) {
dealloc(solvers[i]);
}
if (finished_id == -1) {
switch (ex_kind) {
case ERROR_EX: throw z3_error(error_code);
default: throw default_exception(ex_msg.c_str());
}
}
return result;
}

66
src/sat/sat_ccc.h Normal file
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@ -0,0 +1,66 @@
/*++
Copyright (c) 2017 Microsoft Corporation
Module Name:
sat_ccc.h
Abstract:
A variant of Concurrent Cube and Conquer
Author:
Nikolaj Bjorner (nbjorner) 2017-4-17
Notes:
--*/
#ifndef _SAT_CCC_H_
#define _SAT_CCC_H_
#include "queue.h"
namespace sat {
class ccc {
struct decision {
unsigned m_id;
unsigned m_depth;
literal m_last;
decision(unsigned id, unsigned d, literal last):
m_id(id), m_depth(d), m_last(last) {}
decision(): m_id(0), m_depth(0), m_last(null_literal) {}
};
solver& s;
queue<unsigned> m_solved;
queue<decision> m_decisions;
model m_model;
volatile bool m_cancel;
struct config {
config() {
}
};
struct stats {
stats() { reset(); }
void reset() { memset(this, 0, sizeof(*this)); }
};
lbool conquer(solver& s);
lbool bounded_search(solver& s, unsigned_vector& ids);
lbool cube();
public:
ccc(solver& s): s(s) {}
lbool search();
};
}
#endif

View file

@ -82,6 +82,7 @@ namespace sat {
m_max_conflicts = p.max_conflicts();
m_num_threads = p.threads();
m_local_search = p.local_search();
m_local_search_threads = p.local_search_threads();
m_lookahead_search = p.lookahead_search();
// These parameters are not exposed

View file

@ -58,7 +58,8 @@ namespace sat {
unsigned m_burst_search;
unsigned m_max_conflicts;
unsigned m_num_threads;
unsigned m_local_search;
unsigned m_local_search_threads;
bool m_local_search;
bool m_lookahead_search;
unsigned m_simplify_mult1;

View file

@ -61,6 +61,8 @@ namespace sat {
class lookahead {
solver& s;
friend class ccc;
struct config {
double m_dl_success;
float m_alpha;
@ -70,6 +72,7 @@ namespace sat {
unsigned m_level_cand;
float m_delta_rho;
unsigned m_dl_max_iterations;
unsigned m_tc1_limit;
config() {
m_max_hlevel = 50;
@ -79,6 +82,7 @@ namespace sat {
m_level_cand = 600;
m_delta_rho = (float)0.9995;
m_dl_max_iterations = 32;
m_tc1_limit = 10000000;
}
};
@ -126,6 +130,8 @@ namespace sat {
vector<literal_vector> m_binary; // literal: binary clauses
unsigned_vector m_binary_trail; // trail of added binary clauses
unsigned_vector m_binary_trail_lim;
unsigned m_num_tc1;
unsigned_vector m_num_tc1_lim;
unsigned m_qhead; // propagation queue head
unsigned_vector m_qhead_lim;
clause_vector m_clauses; // non-binary clauses
@ -314,8 +320,11 @@ namespace sat {
assign(u);
return false;
}
IF_VERBOSE(3, verbose_stream() << "tc1: " << u << " " << w << "\n";);
add_binary(u, w);
if (m_num_tc1 < m_config.m_tc1_limit) {
++m_num_tc1;
IF_VERBOSE(3, verbose_stream() << "tc1: " << u << " " << w << "\n";);
add_binary(u, w);
}
}
}
return true;
@ -1055,11 +1064,10 @@ namespace sat {
unsigned trail_sz = s.init_trail_size();
for (unsigned i = 0; i < trail_sz; ++i) {
literal l = s.m_trail[i];
if (!s.was_eliminated(l.var()))
{
if (s.m_config.m_drat) m_drat.add(l, false);
assign(l);
}
if (!s.was_eliminated(l.var())) {
if (s.m_config.m_drat) m_drat.add(l, false);
assign(l);
}
}
propagate();
m_qhead = m_trail.size();
@ -1090,6 +1098,7 @@ namespace sat {
SASSERT(m_search_mode == lookahead_mode::searching);
m_binary_trail_lim.push_back(m_binary_trail.size());
m_trail_lim.push_back(m_trail.size());
m_num_tc1_lim.push_back(m_num_tc1);
m_retired_clause_lim.push_back(m_retired_clauses.size());
m_retired_ternary_lim.push_back(m_retired_ternary.size());
m_qhead_lim.push_back(m_qhead);
@ -1116,6 +1125,9 @@ namespace sat {
}
m_trail.shrink(old_sz); // reset assignment.
m_trail_lim.pop_back();
m_num_tc1 = m_num_tc1_lim.back();
m_num_tc1_lim.pop_back();
// unretire clauses
old_sz = m_retired_clause_lim.back();
@ -1792,11 +1804,17 @@ namespace sat {
return out;
}
void init_search() {
m_search_mode = lookahead_mode::searching;
scoped_level _sl(*this, c_fixed_truth);
init();
}
public:
lookahead(solver& s) :
s(s),
m_drat(s),
m_num_tc1(0),
m_level(2),
m_prefix(0) {
}
@ -1806,11 +1824,7 @@ namespace sat {
}
lbool check() {
{
m_search_mode = lookahead_mode::searching;
scoped_level _sl(*this, c_fixed_truth);
init();
}
init_search();
return search();
}

View file

@ -28,6 +28,7 @@ def_module_params('sat',
('drat.check', BOOL, False, 'build up internal proof and check'),
('cardinality.solver', BOOL, False, 'use cardinality solver'),
('xor.solver', BOOL, False, 'use xor solver'),
('local_search', UINT, 0, 'number of local search threads to find satisfiable solution'),
('local_search_threads', UINT, 0, 'number of local search threads to find satisfiable solution'),
('local_search', BOOL, False, 'use local search instead of CDCL'),
('lookahead_search', BOOL, False, 'use lookahead solver')
))

View file

@ -787,7 +787,10 @@ namespace sat {
if (m_config.m_lookahead_search && num_lits == 0) {
return lookahead_search();
}
if ((m_config.m_num_threads > 1 || m_config.m_local_search > 0) && !m_par) {
if (m_config.m_local_search) {
return do_local_search(num_lits, lits);
}
if ((m_config.m_num_threads > 1 || m_config.m_local_search_threads > 0) && !m_par) {
return check_par(num_lits, lits);
}
flet<bool> _searching(m_searching, true);
@ -859,6 +862,18 @@ namespace sat {
ERROR_EX
};
lbool solver::do_local_search(unsigned num_lits, literal const* lits) {
scoped_limits scoped_rl(rlimit());
local_search srch;
srch.config().set_seed(m_config.m_random_seed);
srch.import(*this, false);
scoped_rl.push_child(&srch.rlimit());
lbool r = srch.check(num_lits, lits, 0);
m_model = srch.get_model();
// srch.collect_statistics(m_lookahead_stats);
return r;
}
lbool solver::lookahead_search() {
lookahead lh(*this);
lbool r = l_undef;
@ -876,9 +891,9 @@ namespace sat {
lbool solver::check_par(unsigned num_lits, literal const* lits) {
scoped_ptr_vector<local_search> ls;
int num_threads = static_cast<int>(m_config.m_num_threads + m_config.m_local_search);
int num_threads = static_cast<int>(m_config.m_num_threads + m_config.m_local_search_threads);
int num_extra_solvers = m_config.m_num_threads - 1;
int num_local_search = static_cast<int>(m_config.m_local_search);
int num_local_search = static_cast<int>(m_config.m_local_search_threads);
for (int i = 0; i < num_local_search; ++i) {
local_search* l = alloc(local_search);
l->config().set_seed(m_config.m_random_seed + i);

View file

@ -160,6 +160,7 @@ namespace sat {
friend class lookahead;
friend class local_search;
friend struct mk_stat;
friend class ccc;
public:
solver(params_ref const & p, reslimit& l);
~solver();
@ -349,6 +350,7 @@ namespace sat {
void exchange_par();
lbool check_par(unsigned num_lits, literal const* lits);
lbool lookahead_search();
lbool do_local_search(unsigned num_lits, literal const* lits);
// -----------------------
//
@ -465,7 +467,7 @@ namespace sat {
lbool get_consequences(literal_vector const& assms, bool_var_vector const& vars, vector<literal_vector>& conseq);
// initialize and retrieve local search.
local_search& init_local_search();
// local_search& init_local_search();
private:

View file

@ -57,6 +57,7 @@ static void throw_out_of_memory() {
{
g_memory_out_of_memory = true;
}
if (g_exit_when_out_of_memory) {
std::cerr << g_out_of_memory_msg << "\n";
exit(ERR_MEMOUT);

61
src/util/queue.h Normal file
View file

@ -0,0 +1,61 @@
/*++
Copyright (c) 2017 Microsoft Corporation
Module Name:
queue.h
Abstract:
Generic queue.
Author:
Nikolaj Bjorner (nbjorner) 2017-4-17
Notes:
--*/
#ifndef _QUEUE_H_
#define _QUEUE_H_
#include "vector.h"
template<class T>
class queue {
vector<T> m_elems;
unsigned m_head;
unsigned m_capacity;
public:
queue(): m_head(0), m_capacity(0) {}
void push(T const& t) { m_elems.push_back(t); }
bool empty() const {
return m_head == m_elems.size();
}
T top() const {
return m_elems[m_head];
}
T pop() {
SASSERT(!empty());
m_capacity = std::max(m_capacity, m_elems.size());
SASSERT(m_head < m_elems.size());
if (2 * m_head > m_capacity && m_capacity > 10) {
for (unsigned i = 0; i < m_elems.size() - m_head; ++i) {
m_elems[i] = m_elems[i + m_head];
}
m_elems.shrink(m_elems.size() - m_head);
m_head = 0;
}
return m_elems[m_head++];
}
};
#endif