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align updated version of lookahead with legacy heuristics

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This commit is contained in:
Nikolaj Bjorner 2024-12-29 21:22:32 -08:00
parent 6ea68310c9
commit d81de1a67e
4 changed files with 257 additions and 145 deletions
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8
src/ast/sls/sls_bv_engine.cpp
View file

@ -96,7 +96,6 @@ double sls_engine::top_score() {
for (expr* e : m_assertions) { for (expr* e : m_assertions) {
top_sum += m_tracker.get_score(e); top_sum += m_tracker.get_score(e);
} }
TRACE("sls_top", tout << "Score distribution:"; TRACE("sls_top", tout << "Score distribution:";
for (expr* e : m_assertions) for (expr* e : m_assertions)
tout << " " << m_tracker.get_score(e); tout << " " << m_tracker.get_score(e);
@ -466,7 +465,6 @@ lbool sls_engine::search() {
// randomize if no increasing move was found // randomize if no increasing move was found
if (new_const == static_cast<unsigned>(-1)) { if (new_const == static_cast<unsigned>(-1)) {
score = old_score;
if (m_walksat_repick) if (m_walksat_repick)
m_evaluator.randomize_local(m_assertions); m_evaluator.randomize_local(m_assertions);
else else
@ -481,16 +479,16 @@ lbool sls_engine::search() {
// smooth weights with probability sp / 1024 // smooth weights with probability sp / 1024
if (m_tracker.get_random_uint(10) < m_paws_sp) if (m_tracker.get_random_uint(10) < m_paws_sp)
{ {
if (m_mpz_manager.eq(m_tracker.get_value(q),m_one)) if (m_mpz_manager.eq(m_tracker.get_value(q), m_one))
m_tracker.decrease_weight(q); m_tracker.decrease_weight(q);
} }
// increase weights otherwise // increase weights otherwise
else else
{ {
if (m_mpz_manager.eq(m_tracker.get_value(q),m_zero)) if (m_mpz_manager.eq(m_tracker.get_value(q), m_zero))
m_tracker.increase_weight(q); m_tracker.increase_weight(q);
} }
} }
} }
} }
// otherwise, apply most increasing move // otherwise, apply most increasing move

4
src/ast/sls/sls_bv_fixed.cpp
View file

@ -27,9 +27,7 @@ namespace sls {
ctx(ctx) ctx(ctx)
{} {}
void bv_fixed::init() { void bv_fixed::init() {
return;
for (auto e : ctx.subterms()) for (auto e : ctx.subterms())
set_fixed(e); set_fixed(e);

340
src/ast/sls/sls_bv_lookahead.cpp
View file

@ -33,11 +33,12 @@ namespace sls {
m(ev.m) { m(ev.m) {
} }
void bv_lookahead::init_updates() { void bv_lookahead::start_propagation() {
m_best_expr = nullptr; if (m_stats.m_num_propagations++ % m_config.propagation_base == 0)
search();
} }
lbool bv_lookahead::search() { void bv_lookahead::search() {
updt_params(ctx.get_params()); updt_params(ctx.get_params());
rescore(); rescore();
m_config.max_moves = m_stats.m_moves + m_config.max_moves_base; m_config.max_moves = m_stats.m_moves + m_config.max_moves_base;
@ -50,92 +51,181 @@ namespace sls {
auto& vars = get_candidate_uninterp(); auto& vars = get_candidate_uninterp();
if (vars.empty()) if (vars.empty())
return l_true; return;
// random walk with probability 1000/wp // random walk with probability 1024/wp
if (ctx.rand(10) < m_config.wp && apply_random_update(vars)) if (ctx.rand(2047) < m_config.wp && apply_random_move(vars))
continue; continue;
if (apply_guided_update(vars)) if (apply_guided_move(vars))
continue; continue;
apply_random_update(vars); if (apply_random_update(get_candidate_uninterp()))
recalibrate_weights(); recalibrate_weights();
} }
m_config.max_moves_base += 100; m_config.max_moves_base += 100;
return l_undef;
} }
bool bv_lookahead::apply_guided_update(ptr_vector<expr> const& vars) { bool bv_lookahead::apply_guided_move(ptr_vector<expr> const& vars) {
init_updates(); m_best_expr = nullptr;
double old_top_score = m_top_score; m_best_score = m_top_score;
for (auto u : vars) unsigned sz = vars.size();
add_updates(u); unsigned start = ctx.rand(sz);
m_top_score = old_top_score; for (unsigned i = 0; i < sz; ++i)
return apply_update(); add_updates(vars[(start + i) % sz]);
TRACE("bv", tout << "guided update " << m_best_score << " " << (m_best_expr?"no update":"") << "\n";);
if (!m_best_expr)
return false;
apply_update(m_best_expr, m_best_value);
//verbose_stream() << "increasing move " << mk_bounded_pp(m_best_expr, m)
// << " := " << m_best_value << " score: " << m_top_score << "\n";
return true;
} }
ptr_vector<expr> const& bv_lookahead::get_candidate_uninterp() { ptr_vector<expr> const& bv_lookahead::get_candidate_uninterp() {
auto const& lits = ctx.root_literals(); auto const& lits = ctx.root_literals();
unsigned start = ctx.rand(lits.size()); app* e = nullptr;
for (unsigned i = 0; i < lits.size(); ++i) { if (m_config.ucb) {
auto lit = lits[(i + start) % lits.size()]; double max = -1.0;
auto e = ctx.atom(lit.var()); for (auto lit : ctx.root_literals()) {
if (!e || !is_app(e)) if (!is_false_bv_literal(lit))
continue; continue;
app* a = to_app(e); auto a = to_app(ctx.atom(lit.var()));
if (!m_ev.can_eval1(a)) auto score = old_score(a);
continue; auto q = score
if (m_ev.bval0(a) == m_ev.bval1(a)) + m_config.ucb_constant * sqrt(log((double)m_touched) / get_touched(a))
continue; + m_config.ucb_noise * ctx.rand(512);
auto const& vars = m_ev.terms.uninterp_occurs(a); if (q > max)
VERIFY(!vars.empty()); max = q, e = a;
TRACE("bv", tout << "candidates " << mk_bounded_pp(e, m) << ": "; }
for (auto e : vars) tout << mk_bounded_pp(e, m) << " "; if (e) {
tout << "\n";); m_touched++;
return vars; inc_touched(e);
}
} }
return m_empty_vars; else {
unsigned n = 0;
for (auto lit : ctx.root_literals())
if (is_false_bv_literal(lit) && ctx.rand() % ++n == 0)
e = to_app(ctx.atom(lit.var()));
}
if (!e)
return m_empty_vars;
auto const& vars = m_ev.terms.uninterp_occurs(e);
VERIFY(!vars.empty());
TRACE("bv", tout << "candidates " << mk_bounded_pp(e, m) << ": ";
for (auto e : vars) tout << mk_bounded_pp(e, m) << " ";
tout << "\n";);
return vars;
} }
bool bv_lookahead::apply_random_update(ptr_vector<expr> const& vars) {
expr* e = vars[ctx.rand(vars.size())];
auto& v = wval(e);
m_v_updated.set_bw(v.bw);
v.get_variant(m_v_updated, m_ev.m_rand);
if (!v.can_set(m_v_updated))
return false;
apply_update(e, m_v_updated);
bool bv_lookahead::apply_random_update(ptr_vector<expr> const& vars) { //verbose_stream() << "random update " << mk_bounded_pp(e, m) << " := " << m_v_updated << " score " << m_top_score << "\n";
while (true) { return true;
expr* e = vars[ctx.rand(vars.size())]; }
auto& v = wval(e);
m_v_updated.set_bw(v.bw); bool bv_lookahead::apply_random_move(ptr_vector<expr> const& vars) {
v.get_variant(m_v_updated, m_ev.m_rand); expr* e = vars[ctx.rand(vars.size())];
v.eval = m_v_updated; auto& v = wval(e);
if (!v.commit_eval()) m_v_updated.set_bw(v.bw);
continue; v.bits().copy_to(v.nw, m_v_updated);
apply_update(e, m_v_updated); switch (ctx.rand(3)) {
case 0: {
// flip a random bit
auto bit = ctx.rand(v.bw);
m_v_updated.set(bit, !m_v_updated.get(bit));
break; break;
} }
case 1:
v.add1(m_v_updated);
break;
default:
v.sub1(m_v_updated);
break;
}
if (!v.can_set(m_v_updated))
return false;
apply_update(e, m_v_updated);
TRACE("bv", tout << "random move " << mk_bounded_pp(e, m) << " := " << m_v_updated << "\n";);
// verbose_stream() << "random move " << mk_bounded_pp(e, m) << " := " << m_v_updated << " score " << m_top_score << "\n";
return true; return true;
} }
void bv_lookahead::check_restart() { void bv_lookahead::check_restart() {
if (m_stats.m_moves % m_config.restart_base == 0) if (m_stats.m_moves % m_config.restart_base == 0) {
// ucb_forget(); ucb_forget();
rescore(); rescore();
}
if (m_stats.m_moves < m_config.restart_next) if (m_stats.m_moves < m_config.restart_next)
return; return;
if (m_stats.m_restarts & 1) ++m_stats.m_restarts;
if (0x1 == (m_stats.m_restarts & 0x1))
m_config.restart_next += m_config.restart_base; m_config.restart_next += m_config.restart_base;
else else
m_config.restart_next += (2 << (m_stats.m_restarts >> 1)) * m_config.restart_base; m_config.restart_next += (2 << (m_stats.m_restarts >> 1)) * m_config.restart_base;
m_stats.m_restarts++; reset_uninterp_in_false_literals();
rescore();
// TODO: reset values of uninterpreted to 0
} }
void bv_lookahead::reset_uninterp_in_false_literals() {
auto const& lits = ctx.root_literals();
expr_mark marked;
for (auto lit : ctx.root_literals()) {
if (!is_false_bv_literal(lit))
continue;
app* a = to_app(ctx.atom(lit.var()));
auto const& occs = m_ev.terms.uninterp_occurs(a);
for (auto e : occs) {
if (marked.is_marked(e))
continue;
marked.mark(e);
auto& v = wval(e);
m_v_updated.set_bw(v.bw);
m_v_updated.set_zero();
if (v.can_set(m_v_updated)) {
apply_update(e, m_v_updated);
}
}
}
}
bool bv_lookahead::is_bv_literal(sat::literal lit) {
if (!ctx.is_true(lit))
return false;
auto e = ctx.atom(lit.var());
if (!e || !is_app(e))
return false;
app* a = to_app(e);
return m_ev.can_eval1(a);
}
bool bv_lookahead::is_false_bv_literal(sat::literal lit) {
if (!is_bv_literal(lit))
return false;
app* a = to_app(ctx.atom(lit.var()));
return (m_ev.bval0(a) != m_ev.bval1(a));
}
void bv_lookahead::updt_params(params_ref const& _p) { void bv_lookahead::updt_params(params_ref const& _p) {
sls_params p(_p); sls_params p(_p);
//m_config.max_restarts = p.max_restarts();
m_config.walksat = p.walksat(); m_config.walksat = p.walksat();
m_config.walksat_repick = p.walksat_repick(); m_config.walksat_repick = p.walksat_repick();
m_config.paws_sp = p.paws_sp(); m_config.paws_sp = p.paws_sp();
@ -145,6 +235,12 @@ namespace sls {
m_config.restart_next = m_config.restart_base; m_config.restart_next = m_config.restart_base;
m_config.restart_init = p.restart_init(); m_config.restart_init = p.restart_init();
m_config.early_prune = p.early_prune(); m_config.early_prune = p.early_prune();
m_config.ucb = p.walksat_ucb();
m_config.ucb_constant = p.walksat_ucb_constant();
m_config.ucb_forget = p.walksat_ucb_forget();
m_config.ucb_init = p.walksat_ucb_init();
m_config.ucb_noise = p.walksat_ucb_noise();
} }
double bv_lookahead::new_score(app* a) { double bv_lookahead::new_score(app* a) {
@ -163,7 +259,9 @@ namespace sls {
for (unsigned i = 0; i < vx.bw; ++i) for (unsigned i = 0; i < vx.bw; ++i)
if (vx.bits().get(i) != vy.bits().get(i)) if (vx.bits().get(i) != vy.bits().get(i))
++delta; ++delta;
return 1 - (delta / vx.bw); auto d = 1.0 - (delta / (double)vx.bw);
//verbose_stream() << "hamming distance " << mk_bounded_pp(a, m) << " " << d << "\n";
return d;
} }
else if (bv.is_ule(a, x, y)) { else if (bv.is_ule(a, x, y)) {
auto const& vx = wval(x); auto const& vx = wval(x);
@ -229,12 +327,13 @@ namespace sls {
return 0; return 0;
} }
double bv_lookahead::lookahead(expr* e, bvect const& new_value) { double bv_lookahead::lookahead_update(expr* e, bvect const& new_value) {
SASSERT(bv.is_bv(e)); SASSERT(bv.is_bv(e));
SASSERT(is_uninterp(e)); SASSERT(is_uninterp(e));
SASSERT(m_restore.empty()); SASSERT(m_restore.empty());
bool has_tabu = false; bool has_tabu = false;
double score = m_top_score;
wval(e).eval = new_value; wval(e).eval = new_value;
if (!insert_update(e)) { if (!insert_update(e)) {
@ -254,11 +353,14 @@ namespace sls {
max_depth = std::max(max_depth, get_depth(p)); max_depth = std::max(max_depth, get_depth(p));
} }
} }
else else {
IF_VERBOSE(1, verbose_stream() << "tabu " << mk_bounded_pp(a, m) << "\n");
has_tabu = true; has_tabu = true;
}
}
else if (is_root(a)) {
score += get_weight(a) * (new_score(a) - old_score(a));
} }
else if (is_root(a))
rescore(a);
else if (m.is_bool(a)) else if (m.is_bool(a))
continue; continue;
else { else {
@ -275,17 +377,15 @@ namespace sls {
if (has_tabu) if (has_tabu)
return -10000; return -10000;
if (m_top_score <= 0.000001) return score;
return -10000;
return m_top_score;
} }
void bv_lookahead::try_set(expr* u, bvect const& new_value) { void bv_lookahead::try_set(expr* u, bvect const& new_value) {
if (!wval(u).can_set(new_value)) if (!wval(u).can_set(new_value))
return; return;
auto score = lookahead(u, new_value); auto score = lookahead_update(u, new_value);
++m_stats.m_num_updates; ++m_stats.m_num_updates;
verbose_stream() << mk_bounded_pp(u, m) << " " << new_value << " score: " << score << "\n"; //verbose_stream() << mk_bounded_pp(u, m) << " := " << new_value << " score: " << score << "\n";
if (score > m_best_score) { if (score > m_best_score) {
m_best_score = score; m_best_score = score;
m_best_expr = u; m_best_expr = u;
@ -323,12 +423,6 @@ namespace sls {
if (v.bw <= 1) if (v.bw <= 1)
return; return;
// invert
for (unsigned i = 0; i < v.nw; ++i)
m_v_updated[i] = ~m_v_updated[i];
v.clear_overflow_bits(m_v_updated);
try_set(u, m_v_updated);
// increment // increment
m_v_saved.copy_to(v.nw, m_v_updated); m_v_saved.copy_to(v.nw, m_v_updated);
v.add1(m_v_updated); v.add1(m_v_updated);
@ -339,16 +433,12 @@ namespace sls {
v.sub1(m_v_updated); v.sub1(m_v_updated);
try_set(u, m_v_updated); try_set(u, m_v_updated);
// reset to original value // invert
try_set(u, m_v_saved); m_v_saved.copy_to(v.nw, m_v_updated);
} for (unsigned i = 0; i < v.nw; ++i)
m_v_updated[i] = ~m_v_updated[i];
bool bv_lookahead::apply_update() { v.clear_overflow_bits(m_v_updated);
CTRACE("bv", !m_best_expr, tout << "no update\n"); try_set(u, m_v_updated);
if (!m_best_expr)
return false;
apply_update(m_best_expr, m_best_value);
return true;
} }
void bv_lookahead::apply_update(expr* e, bvect const& new_value) { void bv_lookahead::apply_update(expr* e, bvect const& new_value) {
@ -357,6 +447,7 @@ namespace sls {
SASSERT(is_uninterp(e)); SASSERT(is_uninterp(e));
SASSERT(m_restore.empty()); SASSERT(m_restore.empty());
wval(e).eval = new_value; wval(e).eval = new_value;
double old_top_score = m_top_score;
//verbose_stream() << mk_bounded_pp(e, m) << " := " << new_value << "\n"; //verbose_stream() << mk_bounded_pp(e, m) << " := " << new_value << "\n";
@ -370,6 +461,7 @@ namespace sls {
m_ev.eval(e); // updates wval(e).eval m_ev.eval(e); // updates wval(e).eval
if (!wval(e).commit_eval()) { if (!wval(e).commit_eval()) {
TRACE("bv", tout << "failed to commit " << mk_bounded_pp(e, m) << " " << wval(e) << "\n"); TRACE("bv", tout << "failed to commit " << mk_bounded_pp(e, m) << " " << wval(e) << "\n");
IF_VERBOSE(0, verbose_stream() << "failed to commit " << mk_bounded_pp(e, m) << " " << wval(e) << "\n");
// bv_plugin::is_sat picks up discrepancies // bv_plugin::is_sat picks up discrepancies
continue; continue;
} }
@ -379,7 +471,9 @@ namespace sls {
} }
} }
else if (is_root(e)) { else if (is_root(e)) {
rescore(e); double score = new_score(e);
m_top_score += get_weight(e) * (score - old_score(e));
set_score(e, score);
} }
else if (m.is_bool(e)) else if (m.is_bool(e))
continue; continue;
@ -390,6 +484,8 @@ namespace sls {
m_update_stack[depth].reset(); m_update_stack[depth].reset();
} }
m_in_update_stack.reset(); m_in_update_stack.reset();
TRACE("bv", tout << mk_bounded_pp(e, m) << " := "
<< new_value << " " << m_top_score << " (" << old_top_score << ")\n");
} }
bool bv_lookahead::insert_update(expr* e) { bool bv_lookahead::insert_update(expr* e) {
@ -427,77 +523,79 @@ namespace sls {
return m_on_restore.is_marked(e); return m_on_restore.is_marked(e);
} }
unsigned bv_lookahead::get_weight(expr* e) { bv_lookahead::bool_info& bv_lookahead::get_bool_info(expr* e) {
return m_bool_info.insert_if_not_there(e, { m_config.paws_init, 0 }).weight; return m_bool_info.insert_if_not_there(e, { m_config.paws_init, 0, 1});
}
void bv_lookahead::inc_weight(expr* e) {
m_bool_info.insert_if_not_there(e, { m_config.paws_init, 0 }).weight += 1;
} }
void bv_lookahead::dec_weight(expr* e) { void bv_lookahead::dec_weight(expr* e) {
auto& w = m_bool_info.insert_if_not_there(e, { m_config.paws_init, 0 }).weight; auto& w = get_bool_info(e).weight;
w = w > m_config.paws_init ? w - 1 : m_config.paws_init; w = w > m_config.paws_init ? w - 1 : m_config.paws_init;
} }
void bv_lookahead::set_score(app* a, double d) {
m_bool_info.insert_if_not_there(a, { m_config.paws_init, 0 }).score = d;
}
double bv_lookahead::old_score(app* a) {
return m_bool_info.insert_if_not_there(a, { m_config.paws_init, 0 }).score;
}
void bv_lookahead::rescore() { void bv_lookahead::rescore() {
m_top_score = 0; m_top_score = 0;
m_rescore = false;
m_is_root.reset(); m_is_root.reset();
for (auto lit : ctx.root_literals()) { for (auto lit : ctx.root_literals()) {
auto e = ctx.atom(lit.var()); if (!is_bv_literal(lit))
if (!e || !is_app(e))
continue; continue;
app* a = to_app(e); auto a = to_app(ctx.atom(lit.var()));
if (!m_ev.can_eval1(a))
continue;
double score = new_score(a); double score = new_score(a);
set_score(a, score); set_score(a, score);
m_top_score += score; m_top_score += score;
m_is_root.mark(a); m_is_root.mark(a);
} }
verbose_stream() << "top score " << m_top_score << "\n";
}
void bv_lookahead::rescore(app* e) {
double score = new_score(e);
m_top_score += get_weight(e) * (score - old_score(e));
set_score(e, score);
} }
void bv_lookahead::recalibrate_weights() { void bv_lookahead::recalibrate_weights() {
for (auto lit : ctx.root_literals()) { for (auto lit : ctx.root_literals()) {
auto e = ctx.atom(lit.var()); if (!is_bv_literal(lit))
if (!e || !is_app(e))
continue; continue;
app* a = to_app(e); auto a = to_app(ctx.atom(lit.var()));
if (!m_ev.can_eval1(a)) bool is_true0 = m_ev.bval0(a);
continue; bool is_true1 = m_ev.bval1(a);
bool is_true = ctx.is_true(lit); if (ctx.rand(2047) < m_config.paws_sp) {
bool is_true_a = m_ev.bval1(a); if (is_true0 == is_true1)
if (ctx.rand(10) < m_config.paws_sp) {
if (is_true == is_true_a)
dec_weight(a); dec_weight(a);
} }
else if (is_true != is_true_a) else if (is_true0 != is_true1)
inc_weight(a); inc_weight(a);
} }
m_best_score = 0;
IF_VERBOSE(20, display_weights(verbose_stream()));
}
std::ostream& bv_lookahead::display_weights(std::ostream& out) {
for (auto lit : ctx.root_literals()) {
if (!is_bv_literal(lit))
continue;
auto a = to_app(ctx.atom(lit.var()));
out
<< get_weight(a) << " "
<< mk_bounded_pp(a, m) << " "
<< old_score(a) << "\n";
}
return out;
}
void bv_lookahead::ucb_forget() {
if (m_config.ucb_forget >= 1.0)
return;
for (auto lit : ctx.root_literals()) {
if (!is_bv_literal(lit))
continue;
auto a = to_app(ctx.atom(lit.var()));
auto touched_old = get_touched(a);
auto touched_new = static_cast<unsigned>((touched_old - 1) * m_config.ucb_forget + 1);
set_touched(a, touched_new);
m_touched += touched_new - touched_old;
}
} }
void bv_lookahead::collect_statistics(statistics& st) const { void bv_lookahead::collect_statistics(statistics& st) const {
st.update("sls-bv-lookahead", m_stats.m_num_lookahead); st.update("sls-bv-lookahead", m_stats.m_num_lookahead);
st.update("sls-bv-updates", m_stats.m_num_updates); st.update("sls-bv-updates", m_stats.m_num_updates);
st.update("sls-bv-moves", m_stats.m_moves); st.update("sls-bv-moves", m_stats.m_moves);
st.update("sls-bv-restarts", m_stats.m_restarts);
} }
} }

50
src/ast/sls/sls_bv_lookahead.h
View file

@ -38,7 +38,13 @@ namespace sls {
unsigned restart_init = 1000; unsigned restart_init = 1000;
bool early_prune = true; bool early_prune = true;
unsigned max_moves = 0; unsigned max_moves = 0;
unsigned max_moves_base = 200; unsigned max_moves_base = 800;
unsigned propagation_base = 10000;
bool ucb = true;
double ucb_constant = 1.0;
double ucb_forget = 0.1;
bool ucb_init = false;
double ucb_noise = 0.1;
}; };
struct stats { struct stats {
@ -46,11 +52,13 @@ namespace sls {
unsigned m_num_updates = 0; unsigned m_num_updates = 0;
unsigned m_moves = 0; unsigned m_moves = 0;
unsigned m_restarts = 0; unsigned m_restarts = 0;
unsigned m_num_propagations = 0;
}; };
struct bool_info { struct bool_info {
unsigned weight = 0; unsigned weight = 40;
double score = 0; double score = 0;
unsigned touched = 1;
}; };
bv_util bv; bv_util bv;
@ -66,51 +74,61 @@ namespace sls {
double m_best_score = 0, m_top_score = 0; double m_best_score = 0, m_top_score = 0;
bvect m_best_value; bvect m_best_value;
expr* m_best_expr = nullptr; expr* m_best_expr = nullptr;
bool m_rescore = true;
ptr_vector<expr> m_empty_vars; ptr_vector<expr> m_empty_vars;
obj_map<expr, bool_info> m_bool_info; obj_map<expr, bool_info> m_bool_info;
expr_mark m_is_root; expr_mark m_is_root;
unsigned m_touched = 1;
void init_updates(); std::ostream& display_weights(std::ostream& out);
bv_valuation& wval(expr* e) const; bv_valuation& wval(expr* e) const;
void insert_update_stack(expr* e); void insert_update_stack(expr* e);
bool insert_update(expr* e); bool insert_update(expr* e);
void restore_lookahead(); void restore_lookahead();
double lookahead(expr* u, bvect const& new_value);
double old_score(app* c); bool_info& get_bool_info(expr* e);
double lookahead_update(expr* u, bvect const& new_value);
double old_score(app* c) { return get_bool_info(c).score; }
void set_score(app* c, double d) { get_bool_info(c).score = d; }
double new_score(app* c); double new_score(app* c);
void set_score(app* c, double d);
void rescore(app* c);
void rescore(); void rescore();
unsigned get_weight(expr* e) { return get_bool_info(e).weight; }
unsigned get_weight(expr* e); void inc_weight(expr* e) { ++get_bool_info(e).weight; }
void inc_weight(expr* e);
void dec_weight(expr* e); void dec_weight(expr* e);
void recalibrate_weights(); void recalibrate_weights();
bool is_root(expr* e) { return m_is_root.is_marked(e); } bool is_root(expr* e) { return m_is_root.is_marked(e); }
void ucb_forget();
unsigned get_touched(app* e) { return get_bool_info(e).touched; }
void set_touched(app* e, unsigned t) { get_bool_info(e).touched = t; }
void inc_touched(app* e) { ++get_bool_info(e).touched; }
void try_set(expr* u, bvect const& new_value); void try_set(expr* u, bvect const& new_value);
void add_updates(expr* u); void add_updates(expr* u);
void apply_update(expr* e, bvect const& new_value); void apply_update(expr* e, bvect const& new_value);
bool apply_update(); bool apply_random_move(ptr_vector<expr> const& vars);
bool apply_guided_move(ptr_vector<expr> const& vars);
bool apply_random_update(ptr_vector<expr> const& vars); bool apply_random_update(ptr_vector<expr> const& vars);
bool apply_guided_update(ptr_vector<expr> const& vars);
ptr_vector<expr> const& get_candidate_uninterp(); ptr_vector<expr> const& get_candidate_uninterp();
void check_restart(); void check_restart();
void reset_uninterp_in_false_literals();
bool is_bv_literal(sat::literal lit);
bool is_false_bv_literal(sat::literal lit);
void search();
public: public:
bv_lookahead(bv_eval& ev); bv_lookahead(bv_eval& ev);
void updt_params(params_ref const& p); void updt_params(params_ref const& p);
lbool search(); void start_propagation();
void start_propagation() { m_rescore = true; }
bool on_restore(expr* e) const; bool on_restore(expr* e) const;