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Cleaned up final SLS version. Enjoy!

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This commit is contained in:
Andreas Froehlich 2014-04-25 13:56:15 +01:00 • committed by Christoph M. Wintersteiger
parent 80c94ef0b6
commit 7d18a17bb3
6 changed files with 94 additions and 146 deletions
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43
src/tactic/sls/sls_engine.cpp
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@ -71,6 +71,8 @@ void sls_engine::updt_params(params_ref const & _p) {
m_restart_init = p.restart_init();
m_early_prune = p.early_prune();
m_random_offset = p.random_offset();
m_rescore = p.rescore();
// Andreas: Would cause trouble because repick requires an assertion being picked before which is not the case in GSAT.
if (m_walksat_repick && !m_walksat)
@ -174,6 +176,9 @@ bool sls_engine::what_if(
m_mpz_manager.del(old_value);
#endif
// Andreas: Had this idea on my last day. Maybe we could add a noise here similar to the one that worked so well for ucb assertion selection.
// r += 0.0001 * m_tracker.get_random_uint(8);
// Andreas: For some reason it is important to use > here instead of >=. Probably related to prefering the LSB.
if (r > best_score) {
best_score = r;
@ -248,9 +253,15 @@ void sls_engine::mk_random_move(ptr_vector<func_decl> & unsat_constants)
{
if (m_mpz_manager.is_one(m_tracker.get_random_bool())) rnd_mv = 2;
if (m_mpz_manager.is_one(m_tracker.get_random_bool())) rnd_mv++;
// Andreas: The other option would be to scale the probability for flips according to the bit-width.
/* unsigned bv_sz2 = m_bv_util.get_bv_size(srt);
rnd_mv = m_tracker.get_random_uint(16) % (bv_sz2 + 3);
if (rnd_mv > 3) rnd_mv = 0; */
move_type mt = (move_type)rnd_mv;
// inversion doesn't make sense, let's do a flip instead.
// Andreas: Christoph claimed inversion doesn't make sense, let's do a flip instead. Is this really true?
if (mt == MV_INV) mt = MV_FLIP;
unsigned bit = 0;
@ -306,10 +317,13 @@ double sls_engine::find_best_move(
unsigned bv_sz;
double new_score = score;
//unsigned offset = m_tracker.get_random_uint(16) % to_evaluate.size();
//for (unsigned j = 0; j < to_evaluate.size(); j++) {
//unsigned i = (j + offset) % to_evaluate.size();
for (unsigned i = 0; i < to_evaluate.size(); i++) {
// Andreas: Introducting a bit of randomization by using a random offset and a random direction to go through the candidate list.
unsigned sz = to_evaluate.size();
unsigned offset = (m_random_offset) ? m_tracker.get_random_uint(16) % sz : 0;
for (unsigned j = 0; j < sz; j++) {
unsigned i = j + offset;
if (i >= sz) i -= sz;
//for (unsigned i = 0; i < to_evaluate.size(); i++) {
func_decl * fd = to_evaluate[i];
sort * srt = fd->get_range();
bv_sz = (m_manager.is_bool(srt)) ? 1 : m_bv_util.get_bv_size(srt);
@ -361,7 +375,13 @@ double sls_engine::find_best_move_mc(ptr_vector<func_decl> & to_evaluate, double
unsigned bv_sz;
double new_score = score;
for (unsigned i = 0; i < to_evaluate.size(); i++) {
// Andreas: Introducting a bit of randomization by using a random offset and a random direction to go through the candidate list.
unsigned sz = to_evaluate.size();
unsigned offset = (m_random_offset) ? m_tracker.get_random_uint(16) % sz : 0;
for (unsigned j = 0; j < sz; j++) {
unsigned i = j + offset;
if (i >= sz) i -= sz;
//for (unsigned i = 0; i < to_evaluate.size(); i++) {
func_decl * fd = to_evaluate[i];
sort * srt = fd->get_range();
bv_sz = (m_manager.is_bool(srt)) ? 1 : m_bv_util.get_bv_size(srt);
@ -405,15 +425,16 @@ lbool sls_engine::search() {
while (check_restart(m_stats.m_moves)) {
checkpoint();
m_stats.m_moves++;
// Andreas: Every base restart interval ...
if (m_stats.m_moves % m_restart_base == 0)
{
// ... potentially smooth the touched counters ...
m_tracker.ucb_forget(m_assertions);
//score = rescore();
// ... or normalize the top-level score.
if (m_rescore) score = rescore();
}
#if _REAL_RS_
//m_tracker.debug_real(g, m_stats.m_moves);
#endif
// get candidate variables
ptr_vector<func_decl> & to_evaluate = m_tracker.get_unsat_constants(m_assertions);
if (!to_evaluate.size())
@ -513,8 +534,6 @@ void sls_engine::operator()(goal_ref const & g, model_converter_ref & mc) {
for (unsigned i = 0; i < g->size(); i++)
assert_expr(g->form(i));
verbose_stream() << "_REAL_RS_ " << _REAL_RS_ << std::endl;
lbool res = operator()();
if (res == l_true) {