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Store only literals in the conflict state

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This commit is contained in:
Jakob Rath 2022-04-11 15:00:06 +02:00
parent fde78f99c3
commit 63031548cb
10 changed files with 73 additions and 145 deletions
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121
src/math/polysat/conflict.cpp
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@ -60,10 +60,16 @@ namespace polysat {
return out;
}
bool conflict::empty() const {
return m_literals.empty()
&& m_vars.empty()
&& m_bail_vars.empty()
&& m_conflict_var == null_var;
}
void conflict::reset() {
for (auto c : *this)
unset_mark(c);
m_constraints.reset();
m_literals.reset();
m_vars.reset();
m_bail_vars.reset();
@ -135,19 +141,15 @@ namespace polysat {
void conflict::insert(signed_constraint c) {
if (c.is_always_true())
return;
if (c->is_marked())
if (is_marked(c))
return;
LOG("inserting: " << c);
SASSERT(!c->vars().empty());
set_mark(c);
if (c->has_bvar())
insert_literal(c.blit());
else
m_constraints.push_back(c);
m_literals.insert(c.blit().index());
}
void conflict::propagate(signed_constraint c) {
cm().ensure_bvar(c.get());
switch (c.bvalue(s)) {
case l_undef:
s.assign_eval(c.blit());
@ -175,13 +177,11 @@ namespace polysat {
* Ensure that c is assigned and justified
*/
void conflict::insert(signed_constraint c, vector<signed_constraint> const& premises) {
keep(c);
// keep(c);
clause_builder c_lemma(s);
for (auto premise : premises) {
LOG_H3("premise: " << premise);
keep(premise);
SASSERT(premise->has_bvar());
// keep(premise);
SASSERT(premise.bvalue(s) != l_false);
c_lemma.push(~premise.blit());
}
@ -194,12 +194,8 @@ namespace polysat {
}
void conflict::remove(signed_constraint c) {
SASSERT(!c->has_bvar() || std::count(m_constraints.begin(), m_constraints.end(), c) == 0);
unset_mark(c);
if (c->has_bvar())
remove_literal(c.blit());
else
m_constraints.erase(c);
m_literals.remove(c.blit().index());
}
void conflict::replace(signed_constraint c_old, signed_constraint c_new, vector<signed_constraint> const& c_new_premises) {
@ -207,12 +203,12 @@ namespace polysat {
insert(c_new, c_new_premises);
}
bool conflict::contains(signed_constraint c) const {
return m_literals.contains(c.blit().index());
}
bool conflict::contains(signed_constraint c) {
if (c->has_bvar())
return m_literals.contains(c.blit().index());
else
return m_constraints.contains(c);
bool conflict::contains(sat::literal lit) const {
return m_literals.contains(lit.index());
}
void conflict::set_bailout() {
@ -228,14 +224,12 @@ namespace polysat {
SASSERT(lit != sat::null_literal);
SASSERT(~lit != sat::null_literal);
SASSERT(std::all_of(m_constraints.begin(), m_constraints.end(), [](signed_constraint const& c){ return !c->has_bvar(); }));
SASSERT(contains_literal(lit));
SASSERT(contains(lit));
SASSERT(std::count(cl.begin(), cl.end(), lit) > 0);
SASSERT(!contains_literal(~lit));
SASSERT(!contains(~lit));
SASSERT(std::count(cl.begin(), cl.end(), ~lit) == 0);
remove_literal(lit);
unset_mark(s.lit2cnstr(lit));
remove(s.lit2cnstr(lit));
for (sat::literal lit2 : cl)
if (lit2 != lit)
insert(s.lit2cnstr(~lit2));
@ -247,9 +241,8 @@ namespace polysat {
SASSERT(lit != sat::null_literal);
SASSERT(~lit != sat::null_literal);
SASSERT(std::all_of(m_constraints.begin(), m_constraints.end(), [](signed_constraint const& c){ return !c->has_bvar(); }));
SASSERT(contains_literal(lit));
SASSERT(!contains_literal(~lit));
SASSERT(contains(lit));
SASSERT(!contains(~lit));
signed_constraint c = s.lit2cnstr(lit);
bool has_decision = false;
@ -260,35 +253,19 @@ namespace polysat {
if (!has_decision) {
remove(c);
for (pvar v : c->vars())
if (s.is_assigned(v))
if (s.is_assigned(v)) {
// TODO: 'lit' was propagated at level 'lvl'; can we here ignore variables above that?
SASSERT(s.get_level(v) <= lvl);
m_vars.insert(v);
}
}
}
/**
* If the constraint c is a temporary constraint derived by core saturation,
* insert it (and recursively, its premises) into \Gamma
*/
void conflict::keep(signed_constraint c) {
if (c->has_bvar())
return;
LOG_H3("keeping: " << c);
remove(c);
cm().ensure_bvar(c.get());
insert(c);
}
clause_builder conflict::build_lemma() {
// SASSERT(std::all_of(m_vars.begin(), m_vars.end(), [&](pvar v) { return s.is_assigned(v); }));
SASSERT(std::all_of(m_constraints.begin(), m_constraints.end(), [](signed_constraint const& c) { return !c->has_bvar(); }));
LOG_H3("Build lemma from core");
LOG("core: " << *this);
clause_builder lemma(s);
while (!m_constraints.empty())
keep(m_constraints.back());
for (auto c : *this)
minimize_vars(c);
@ -297,7 +274,6 @@ namespace polysat {
for (unsigned v : m_vars) {
auto eq = s.eq(s.var(v), s.get_value(v));
cm().ensure_bvar(eq.get());
if (eq.bvalue(s) == l_undef)
s.assign_eval(eq.blit());
lemma.push(~eq);
@ -410,50 +386,27 @@ namespace polysat {
}
void conflict::set_mark(signed_constraint c) {
if (c->is_marked())
return;
c->set_mark();
if (c->has_bvar())
set_bmark(c->bvar());
}
/**
* unset marking on the constraint, but keep variable dependencies.
*/
void conflict::unset_mark(signed_constraint c) {
if (!c->is_marked())
return;
c->unset_mark();
if (c->has_bvar())
unset_bmark(c->bvar());
}
void conflict::set_bmark(sat::bool_var b) {
sat::bool_var b = c->bvar();
if (b >= m_bvar2mark.size())
m_bvar2mark.resize(b + 1);
SASSERT(!m_bvar2mark[b]);
m_bvar2mark[b] = true;
}
void conflict::unset_bmark(sat::bool_var b) {
/**
* unset marking on the constraint, but keep variable dependencies.
*/
void conflict::unset_mark(signed_constraint c) {
sat::bool_var b = c->bvar();
SASSERT(m_bvar2mark[b]);
m_bvar2mark[b] = false;
}
bool conflict::is_bmarked(sat::bool_var b) const {
bool conflict::is_marked(signed_constraint c) const {
return is_marked(c->bvar());
}
bool conflict::is_marked(sat::bool_var b) const {
return m_bvar2mark.get(b, false);
}
bool conflict::contains_literal(sat::literal lit) const {
return m_literals.contains(lit.to_uint());
}
void conflict::insert_literal(sat::literal lit) {
m_literals.insert(lit.to_uint());
}
void conflict::remove_literal(sat::literal lit) {
m_literals.remove(lit.to_uint());
}
}