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include chronological backtracking, two-phase sat, xor inprocessing, probsat, ddfw

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Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>
This commit is contained in:
Nikolaj Bjorner 2019-06-13 03:34:31 -07:00
parent 46d23ea8d7
commit d17248821a
32 changed files with 3246 additions and 654 deletions
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50
src/sat/sat_local_search.cpp
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@ -216,10 +216,10 @@ namespace sat {
void local_search::set_best_unsat() {
m_best_unsat = m_unsat_stack.size();
if (m_best_unsat == 1) {
constraint const& c = m_constraints[m_unsat_stack[0]];
IF_VERBOSE(2, display(verbose_stream() << "single unsat:", c));
}
m_best_phase.reserve(m_vars.size());
for (unsigned i = m_vars.size(); i-- > 0; ) {
m_best_phase[i] = m_vars[i].m_value;
}
}
void local_search::verify_solution() const {
@ -351,7 +351,16 @@ namespace sat {
m_par(nullptr) {
}
void local_search::import(solver& s, bool _init) {
void local_search::reinit(solver& s) {
import(s, true);
if (s.m_best_phase_size > 0) {
for (unsigned i = num_vars(); i-- > 0; ) {
set_phase(i, s.m_best_phase[i]);
}
}
}
void local_search::import(solver const& s, bool _init) {
flet<bool> linit(m_initializing, true);
m_is_pb = false;
m_vars.reset();
@ -364,7 +373,7 @@ namespace sat {
if (m_config.phase_sticky()) {
unsigned v = 0;
for (var_info& vi : m_vars) {
vi.m_bias = s.m_phase[v++] == POS_PHASE ? 98 : 2;
vi.m_bias = s.m_phase[v++] ? 98 : 2;
}
}
@ -495,7 +504,7 @@ namespace sat {
lbool local_search::check() {
return check(0, nullptr);
return check(0, nullptr, nullptr);
}
#define PROGRESS(tries, flips) \
@ -530,7 +539,25 @@ namespace sat {
}
total_flips += step;
PROGRESS(tries, total_flips);
if (m_par && m_par->get_phase(*this)) {
if (m_par) {
double max_avg = 0;
for (unsigned v = 0; v < num_vars(); ++v) {
max_avg = std::max(max_avg, (double)m_vars[v].m_slow_break);
}
double sum = 0;
for (unsigned v = 0; v < num_vars(); ++v) {
sum += exp(m_config.itau() * (m_vars[v].m_slow_break - max_avg));
}
if (sum == 0) {
sum = 0.01;
}
for (unsigned v = 0; v < num_vars(); ++v) {
m_vars[v].m_break_prob = exp(m_config.itau() * (m_vars[v].m_slow_break - max_avg)) / sum;
}
m_par->to_solver(*this);
}
if (m_par && m_par->from_solver(*this)) {
reinit();
}
if (tries % 10 == 0 && !m_unsat_stack.empty()) {
@ -834,11 +861,10 @@ namespace sat {
}
void local_search::set_phase(bool_var v, lbool f) {
void local_search::set_phase(bool_var v, bool f) {
unsigned& bias = m_vars[v].m_bias;
if (f == l_true && bias < 100) bias++;
if (f == l_false && bias > 0) bias--;
// f == l_undef ?
if (f && bias < 100) bias++;
if (!f && bias > 0) bias--;
}
void local_search::set_bias(bool_var v, lbool f) {