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elaborating on local-search rephase strategy

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This commit is contained in:
Nikolaj Bjorner 2023-02-07 03:17:52 -08:00
parent f3ae7692ca
commit 90a75866fb
9 changed files with 131 additions and 56 deletions
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52
src/sat/sat_ddfw.cpp
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@ -57,11 +57,11 @@ namespace sat {
double sec = m_stopwatch.get_current_seconds();
double kflips_per_sec = (m_flips - m_last_flips) / (1000.0 * sec);
if (m_last_flips == 0) {
IF_VERBOSE(0, verbose_stream() << "(sat.ddfw :unsat :models :kflips/sec :flips :restarts :reinits :unsat_vars :shifts";
IF_VERBOSE(1, verbose_stream() << "(sat.ddfw :unsat :models :kflips/sec :flips :restarts :reinits :unsat_vars :shifts";
if (m_par) verbose_stream() << " :par";
verbose_stream() << ")\n");
}
IF_VERBOSE(0, verbose_stream() << "(sat.ddfw "
IF_VERBOSE(1, verbose_stream() << "(sat.ddfw "
<< std::setw(07) << m_min_sz
<< std::setw(07) << m_models.size()
<< std::setw(10) << kflips_per_sec
@ -106,7 +106,6 @@ namespace sat {
if (r > 0) {
lim_pos -= score(r);
if (lim_pos <= 0) {
if (m_par) update_reward_avg(v);
return v;
}
}
@ -139,9 +138,8 @@ namespace sat {
}
void ddfw::add(solver const& s) {
for (auto& ci : m_clauses) {
for (auto& ci : m_clauses)
m_alloc.del_clause(ci.m_clause);
}
m_clauses.reset();
m_use_list.reset();
m_num_non_binary_clauses = 0;
@ -281,6 +279,7 @@ namespace sat {
ci.add(nlit);
}
value(v) = !value(v);
update_reward_avg(v);
}
bool ddfw::should_reinit_weights() {
@ -379,36 +378,35 @@ namespace sat {
return m_par != nullptr && m_flips >= m_parsync_next;
}
void ddfw::save_priorities() {
m_probs.reset();
for (unsigned v = 0; v < num_vars(); ++v)
m_probs.push_back(-m_vars[v].m_reward_avg);
}
void ddfw::do_parallel_sync() {
if (m_par->from_solver(*this)) {
// Sum exp(xi) / exp(a) = Sum exp(xi - a)
double max_avg = 0;
for (unsigned v = 0; v < num_vars(); ++v) {
max_avg = std::max(max_avg, (double)m_vars[v].m_reward_avg);
}
double sum = 0;
for (unsigned v = 0; v < num_vars(); ++v) {
sum += exp(m_config.m_itau * (m_vars[v].m_reward_avg - max_avg));
}
if (sum == 0) {
sum = 0.01;
}
m_probs.reset();
for (unsigned v = 0; v < num_vars(); ++v) {
m_probs.push_back(exp(m_config.m_itau * (m_vars[v].m_reward_avg - max_avg)) / sum);
}
if (m_par->from_solver(*this))
m_par->to_solver(*this);
}
++m_parsync_count;
m_parsync_next *= 3;
m_parsync_next /= 2;
}
void ddfw::save_model() {
m_model.reserve(num_vars());
for (unsigned i = 0; i < num_vars(); ++i)
m_model[i] = to_lbool(value(i));
save_priorities();
}
void ddfw::save_best_values() {
if (m_unsat.empty()) {
m_model.reserve(num_vars());
for (unsigned i = 0; i < num_vars(); ++i)
m_model[i] = to_lbool(value(i));
if (m_unsat.empty())
save_model();
else if (m_unsat.size() < m_min_sz) {
if (m_unsat.size() < 50 || m_min_sz * 10 > m_unsat.size() * 11)
save_model();
}
if (m_unsat.size() < m_min_sz) {
m_models.reset();