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take 1 on flip conditions

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Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>
This commit is contained in:
Nikolaj Bjorner 2024-12-31 11:44:38 -08:00
parent a511b8bcf0
commit b415b82625
7 changed files with 71 additions and 35 deletions
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29
src/ast/sls/sls_bv_lookahead.cpp
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@ -38,6 +38,7 @@ namespace sls {
* before any other propagation with the main BV solver.
*/
void bv_lookahead::start_propagation() {
//verbose_stream() << "start_propagation " << m_stats.m_num_propagations << "\n";
if (m_stats.m_num_propagations++ % m_config.propagation_base == 0)
search();
}
@ -54,6 +55,8 @@ namespace sls {
updt_params(ctx.get_params());
rescore();
m_config.max_moves = m_stats.m_moves + m_config.max_moves_base;
TRACE("bv", tout << "search " << m_stats.m_moves << " " << m_config.max_moves << "\n";);
IF_VERBOSE(3, verbose_stream() << "lookahead-search moves:" << m_stats.m_moves << " max-moves:" << m_config.max_moves << "\n");
while (m.inc() && m_stats.m_moves < m_config.max_moves) {
m_stats.m_moves++;
@ -62,8 +65,8 @@ namespace sls {
// get candidate variables
auto& vars = get_candidate_uninterp();
if (vars.empty())
return;
if (vars.empty())
return;
// random walk
if (ctx.rand(2047) < m_config.wp && apply_random_move(vars))
@ -73,6 +76,9 @@ namespace sls {
if (apply_guided_move(vars))
continue;
if (apply_flip())
return;
// bail out if no progress, and try random update
if (apply_random_update(get_candidate_uninterp()))
recalibrate_weights();
@ -133,6 +139,17 @@ namespace sls {
return apply_update(e, m_v_updated, "random move");
}
bool bv_lookahead::apply_flip() {
if (!m_last_atom)
return false;
auto const& cond = m_ev.terms.condition_occurs(m_last_atom);
if (cond.empty())
return false;
expr* e = cond[ctx.rand(cond.size())];
ctx.flip(ctx.atom2bool_var(e));
return true;
}
/**
* Retrieve a candidate top-level predicate that is false, give preference to
* those with high score, but back off if they are frequently chosen.
@ -163,13 +180,15 @@ namespace sls {
if (is_false_bv_literal(lit) && ctx.rand() % ++n == 0)
e = to_app(ctx.atom(lit.var()));
}
CTRACE("bv", !e, tout << "no candidate\n";
ctx.display(tout);
display_weights(tout););
CTRACE("bv", !e, ; display_weights(ctx.display(tout << "no candidate\n")););
m_last_atom = e;
if (!e)
return m_empty_vars;
auto const& vars = m_ev.terms.uninterp_occurs(e);
TRACE("bv", tout << "candidates " << mk_bounded_pp(e, m) << ": ";