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merge

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Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>
This commit is contained in:
Nikolaj Bjorner 2021-09-10 15:43:36 +02:00
commit af0e4d402b
4 changed files with 78 additions and 16 deletions
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28
src/math/polysat/solver.cpp
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@ -446,6 +446,8 @@ namespace polysat {
LOG_H2("Resolve conflict");
LOG("\n" << *this);
LOG("search state: " << m_search);
for (pvar v = 0; v < m_cjust.size(); ++v)
LOG("cjust[v" << v << "]: " << m_cjust[v]);
++m_stats.m_num_conflicts;
SASSERT(is_conflict());
@ -461,9 +463,10 @@ namespace polysat {
set_marks(m_conflict);
}
for (unsigned i = m_search.size(); i-- > 0; ) {
search_iterator search_it(m_search);
while (search_it.next()) {
LOG("Conflict: " << m_conflict);
auto const& item = m_search[i];
auto const& item = *search_it;
if (item.is_assignment()) {
// Resolve over variable assignment
pvar v = item.var();
@ -620,17 +623,9 @@ namespace polysat {
backjump(lvl - 1);
// TODO: we need to decide_bool on the clause (learn_lemma takes care of this).
// if the lemma was asserting, then this will propagate the last literal. otherwise we do the enumerative guessing as normal.
// we need to exclude the current value of v. narrowing of the guessed constraint *should* take care of it but we cannot count on that.
// TODO: what do we add as 'cjust' for this restriction? the guessed
// constraint from the lemma should be the right choice. but, how to
// carry this over when the guess is reverted? need to remember the
// variable 'v' somewhere on the lemma.
// the restriction v /= val can live before the guess... (probably should ensure that the guess stays close to the current position in the stack to prevent confusion...)
// The justification for this restriction is the guessed constraint from the lemma.
// cjust[v] will be updated accordingly by decide_bool.
m_viable.add_non_viable(v, val);
learn_lemma(v, std::move(lemma));
if (is_conflict()) {
@ -779,8 +774,13 @@ namespace polysat {
if (!lemma)
return;
LOG("Lemma: " << show_deref(lemma));
for (sat::literal l : *lemma)
LOG(" Literal " << l << " is: " << m_constraints.lookup(l));
for (sat::literal lit : *lemma) {
LOG(" Literal " << lit << " is: " << m_constraints.lookup(lit));
// TODO: fully evaluated constraints must be put onto the stack as propagations.
signed_constraint c = m_constraints.lookup(lit);
SASSERT(m_bvars.is_assigned(lit) && !c.is_currently_false(*this));
SASSERT(m_bvars.is_assigned(lit) && !c.is_currently_true(*this));
}
SASSERT(lemma->size() > 0);
clause* cl = m_constraints.store(std::move(lemma));
m_redundant_clauses.push_back(cl);