static lbool core_chunking(sat::solver& s, sat::bool_var_vector& vars, sat::literal_vector const& asms, vector<sat::literal_vector>& conseq, unsigned K) {
lbool r = s.check(asms.size(), asms.c_ptr());
if (r != l_true) {
return r;
}
sat::model const & m = s.get_model();
sat::literal_vector lambda, backbones;
for (unsigned i = 0; i < vars.size(); i++) {
lambda.push_back(sat::literal(vars[i], m[vars[i]] == l_false));
}
while (!lambda.empty()) {
IF_VERBOSE(1, verbose_stream() << "(sat-backbone-core " << lambda.size() << " " << backbones.size() << ")\n";);
unsigned k = std::min(K, lambda.size());
sat::literal_vector gamma, omegaN;
for (unsigned i = 0; i < k; ++i) {
sat::literal l = lambda[lambda.size() - i - 1];
gamma.push_back(l);
omegaN.push_back(~l);
}
while (true) {
sat::literal_vector asms1(asms);
asms1.append(omegaN);
r = s.check(asms1.size(), asms1.c_ptr());
if (r == l_true) {
IF_VERBOSE(1, verbose_stream() << "(sat) " << omegaN << "\n";);
prune_unfixed(lambda, s.get_model());
break;
}
static void brute_force_consequences(sat::solver& s, sat::literal_vector const& asms, sat::literal_vector const& gamma, sat::literal_vector& backbones) {
for (unsigned i = 0; i < gamma.size(); ++i) {
sat::literal nlit = ~gamma[i];
sat::literal_vector asms1(asms);
asms1.push_back(nlit);
lbool r = s.check(asms1.size(), asms1.c_ptr());
if (r == l_false) {
backbones.push_back(gamma[i]);
}
}
}
lbool solver::get_consequences_core(expr_ref_vector const& asms, expr_ref_vector const& vars, expr_ref_vector& consequences) {
ast_manager& m = asms.get_manager();
lbool is_sat = check_sat(asms);
if (is_sat != l_true) {
return is_sat;
}
model_ref model;
get_model(model);
expr_ref tmp(m), nlit(m), lit(m), val(m);
expr_ref_vector asms1(asms);
model_evaluator eval(*model.get());
unsigned k = 0;
for (unsigned i = 0; i < vars.size(); ++i) {
expr_ref_vector core(m);
tmp = vars[i];
val = eval(tmp);
if (!m.is_value(val)) {
continue;
}
if (m.is_bool(tmp) && is_uninterp_const(tmp)) {
if (m.is_true(val)) {
nlit = m.mk_not(tmp);
lit = tmp;
}
else if (m.is_false(val)) {
nlit = tmp;
lit = m.mk_not(tmp);
}
else {
continue;
}
scoped_assumption_push _scoped_push(asms1, nlit);
is_sat = check_sat(asms1);
switch (is_sat) {
case l_undef:
return is_sat;
case l_true:
break;
case l_false:
get_unsat_core(core);
k = 0;
for (unsigned j = 0; j < core.size(); ++j) {
if (core[j].get() != nlit) {
core[k] = core[j].get();
++k;
}
}
core.resize(k);
consequences.push_back(m.mk_implies(mk_and(core), lit));
break;
}
}
else {
lit = m.mk_eq(tmp, val);
nlit = m.mk_not(lit);
scoped_push _scoped_push(*this);
assert_expr(nlit);
is_sat = check_sat(asms);
switch (is_sat) {
case l_undef:
return is_sat;
case l_true:
break;
case l_false:
get_unsat_core(core);
consequences.push_back(m.mk_implies(mk_and(core), lit));
break;
}
}
}
return l_true;
}