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fix drat output for elim_eqs

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>
This commit is contained in:
Nikolaj Bjorner 2019-01-10 15:25:10 -08:00
parent b12c1b1cba
commit 6e60926cc3
4 changed files with 60 additions and 27 deletions

View file

@ -23,9 +23,15 @@ Revision History:
namespace sat {
elim_eqs::elim_eqs(solver & s):
m_solver(s) {
m_solver(s),
m_to_delete(nullptr) {
}
elim_eqs::~elim_eqs() {
dealloc(m_to_delete);
}
inline literal norm(literal_vector const & roots, literal l) {
if (l.sign())
return ~roots[l.var()];
@ -86,6 +92,12 @@ namespace sat {
m_new_bin.reset();
}
void elim_eqs::drat_delete_clause() {
if (m_solver.m_config.m_drat) {
m_solver.m_drat.del(*m_to_delete->get());
}
}
void elim_eqs::cleanup_clauses(literal_vector const & roots, clause_vector & cs) {
clause_vector::iterator it = cs.begin();
clause_vector::iterator it2 = it;
@ -107,8 +119,16 @@ namespace sat {
it2++;
continue;
}
if (!c.frozen())
if (!c.frozen()) {
m_solver.detach_clause(c);
}
// save clause to be deleted for drat
if (m_solver.m_config.m_drat) {
if (!m_to_delete) m_to_delete = alloc(tmp_clause);
m_to_delete->set(sz, c.begin(), c.is_learned());
}
// apply substitution
for (i = 0; i < sz; i++) {
literal lit = c[i];
@ -124,60 +144,69 @@ namespace sat {
CTRACE("sat", l != norm(roots, l), tout << l << " " << norm(roots, l) << "\n"; tout.flush(););
SASSERT(l == norm(roots, l));
} });
// remove duplicates, and check if it is a tautology
literal l_prev = null_literal;
unsigned j = 0;
literal l_prev = null_literal;
for (i = 0; i < sz; i++) {
literal l = c[i];
if (l == l_prev)
continue;
if (l == ~l_prev)
if (l == ~l_prev) {
break;
}
if (l == l_prev) {
continue;
}
SASSERT(l != ~l_prev);
l_prev = l;
lbool val = m_solver.value(l);
if (val == l_true)
break; // clause was satisfied
if (val == l_false)
if (val == l_true) {
break;
}
if (val == l_false) {
continue; // skip
}
c[j] = l;
j++;
}
TRACE("elim_eqs", tout << "after removing duplicates: " << c << " j: " << j << "\n";);
if (i < sz) {
// clause is a tautology or was simplified to true
m_solver.del_clause(c);
drat_delete_clause();
m_solver.del_clause(c, false);
continue;
}
if (j == 0) {
// empty clause
switch (j) {
case 0:
m_solver.set_conflict(justification());
for (; it != end; ++it) {
*it2 = *it;
it2++;
}
cs.set_end(it2);
return;
}
TRACE("elim_eqs", tout << "after removing duplicates: " << c << " j: " << j << "\n";);
SASSERT(j >= 1);
switch (j) {
return;
case 1:
m_solver.assign(c[0], justification());
m_solver.del_clause(c);
m_solver.del_clause(c, false);
drat_delete_clause();
break;
case 2:
m_solver.mk_bin_clause(c[0], c[1], c.is_learned());
m_solver.del_clause(c);
m_solver.del_clause(c, false);
drat_delete_clause();
break;
default:
SASSERT(*it == &c);
if (j < sz) {
if (m_solver.m_config.m_drat) m_solver.m_drat.del(c);
c.shrink(j);
if (m_solver.m_config.m_drat) m_solver.m_drat.add(c, true);
}
else
else {
c.update_approx();
}
if (m_solver.m_config.m_drat) {
m_solver.m_drat.add(c, true);
drat_delete_clause();
}
DEBUG_CODE(for (literal l : c) VERIFY(l == norm(roots, l)););