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fix pbge and reduce_tr

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Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>
This commit is contained in:
Nikolaj Bjorner 2018-03-13 09:07:58 -07:00
parent e7d43ed516
commit 64954cc551
8 changed files with 83 additions and 23 deletions
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5
src/ast/rewriter/pb_rewriter.cpp
View file

@ -296,8 +296,7 @@ br_status pb_rewriter::mk_app_core(func_decl * f, unsigned num_args, expr * cons
slack -= c;
k -= c;
}
else if (c >= k) {
slack -= c;
else if (c >= k && k.is_pos()) {
disj.push_back(m_args[i]);
}
else {
@ -309,7 +308,7 @@ br_status pb_rewriter::mk_app_core(func_decl * f, unsigned num_args, expr * cons
m_args.shrink(j);
m_coeffs.shrink(j);
sz = j;
if (k.is_pos() && sz > 0 && slack >= k) {
if (sz > 0) {
disj.push_back(m_util.mk_ge(sz, m_coeffs.c_ptr(), m_args.c_ptr(), k));
}
if (!disj.empty()) {

29
src/sat/sat_big.cpp
View file

@ -165,9 +165,11 @@ namespace sat {
}
unsigned big::reduce_tr(solver& s) {
unsigned num_lits = s.num_vars() * 2;
unsigned idx = 0;
unsigned elim = 0;
m_del_bin.reset();
for (watch_list & wlist : s.m_watches) {
if (s.inconsistent()) break;
literal u = to_literal(idx++);
@ -178,8 +180,9 @@ namespace sat {
watched& w = *it;
if (learned() ? w.is_binary_learned_clause() : w.is_binary_clause()) {
literal v = w.get_literal();
if (reaches(u, v) && u != get_parent(v)) {
if (u != get_parent(v) && safe_reach(u, v)) {
++elim;
m_del_bin.push_back(std::make_pair(~u, v));
if (find_binary_watch(wlist, ~v)) {
IF_VERBOSE(10, verbose_stream() << "binary: " << ~u << "\n");
s.assign(~u, justification());
@ -193,11 +196,33 @@ namespace sat {
itprev++;
}
wlist.set_end(itprev);
}
}
s.propagate(false);
return elim;
}
bool big::safe_reach(literal u, literal v) {
if (!reaches(u, v)) return false;
while (u != v) {
literal w = next(u, v);
if (m_del_bin.contains(std::make_pair(~u, w)) ||
m_del_bin.contains(std::make_pair(~w, u))) {
return false;
}
u = w;
}
return true;
}
literal big::next(literal u, literal v) const {
SASSERT(reaches(u, v));
for (literal w : m_dag[u.index()]) {
if (reaches(u, w) && (w == v || reaches(w, v))) return w;
}
UNREACHABLE();
return null_literal;
}
void big::display(std::ostream& out) const {
unsigned idx = 0;
for (auto& next : m_dag) {

6
src/sat/sat_big.h
View file

@ -36,9 +36,15 @@ namespace sat {
bool m_learned;
bool m_binary; // is the BIG produced from binary clauses or hyper-binary resolution?
svector<std::pair<literal, literal>> m_del_bin;
void init_dfs_num();
struct pframe;
bool safe_reach(literal u, literal v);
literal next(literal u, literal v) const;
public:
big(random_gen& rand);

36
src/sat/sat_elim_eqs.cpp
View file

@ -33,17 +33,18 @@ namespace sat {
return roots[l.var()];
}
void elim_eqs::cleanup_bin_watches(literal_vector const & roots) {
void elim_eqs::cleanup_bin_watches(literal_vector const & roots) {
unsigned l_idx = 0;
m_new_bin.reset();
for (watch_list & wlist : m_solver.m_watches) {
literal l1 = ~to_literal(l_idx++);
literal r1 = norm(roots, l1);
watch_list::iterator it2 = wlist.begin();
watch_list::iterator itprev = it2;
watch_list::iterator end2 = wlist.end();
for (; it2 != end2; ++it2) {
if (it2->is_binary_clause()) {
literal l2 = it2->get_literal();
watch_list::iterator it = wlist.begin();
watch_list::iterator itprev = it;
watch_list::iterator end = wlist.end();
for (; it != end; ++it) {
if (it->is_binary_clause()) {
literal l2 = it->get_literal();
literal r2 = norm(roots, l2);
if (r1 == r2) {
m_solver.assign(r1, justification());
@ -56,18 +57,33 @@ namespace sat {
// consume tautology
continue;
}
#if 0
if (l1 != r1) {
// add half r1 => r2, the other half ~r2 => ~r1 is added when traversing l2
m_solver.m_watches[(~r1).index()].push_back(watched(r2, it2->is_learned()));
m_solver.m_watches[(~r1).index()].push_back(watched(r2, it->is_learned()));
continue;
}
it2->set_literal(r2); // keep it
it->set_literal(r2); // keep it.
#else
if (l1 != r1 || l2 != r2) {
if (r1.index() < r2.index()) {
m_new_bin.push_back(bin(r1, r2, it->is_learned()));
}
continue;
}
// keep it
#endif
}
*itprev = *it2;
*itprev = *it;
itprev++;
}
wlist.set_end(itprev);
}
for (auto const& b : m_new_bin) {
m_solver.mk_bin_clause(b.l1, b.l2, b.learned);
}
m_new_bin.reset();
}
void elim_eqs::cleanup_clauses(literal_vector const & roots, clause_vector & cs) {

6
src/sat/sat_elim_eqs.h
View file

@ -25,6 +25,12 @@ namespace sat {
class solver;
class elim_eqs {
struct bin {
literal l1, l2;
bool learned;
bin(literal l1, literal l2, bool learned): l1(l1), l2(l2), learned(learned) {}
};
svector<bin> m_new_bin;
solver & m_solver;
void save_elim(literal_vector const & roots, bool_var_vector const & to_elim);
void cleanup_clauses(literal_vector const & roots, clause_vector & cs);

2
src/sat/sat_scc.cpp
View file

@ -222,7 +222,7 @@ namespace sat {
}
}
TRACE("scc", for (unsigned i = 0; i < roots.size(); i++) { tout << i << " -> " << roots[i] << "\n"; }
tout << "to_elim: "; for (unsigned i = 0; i < to_elim.size(); i++) tout << to_elim[i] << " "; tout << "\n";);
tout << "to_elim: "; for (literal l : to_elim) tout << l << " "; tout << "\n";);
m_num_elim += to_elim.size();
elim_eqs eliminator(m_solver);
eliminator(roots, to_elim);

21
src/sat/sat_solver.cpp
View file

@ -1632,7 +1632,6 @@ namespace sat {
IF_VERBOSE(10, verbose_stream() << "\"checking model\"\n";);
if (!check_clauses(m_model)) {
UNREACHABLE();
throw solver_exception("check model failed");
}
@ -1644,7 +1643,6 @@ namespace sat {
if (!check_clauses(m_model)) {
IF_VERBOSE(0, verbose_stream() << "failure checking clauses on transformed model\n";);
UNREACHABLE();
throw solver_exception("check model failed");
}
@ -1652,8 +1650,12 @@ namespace sat {
if (m_clone) {
IF_VERBOSE(SAT_VB_LVL, verbose_stream() << "\"checking model (on original set of clauses)\"\n";);
if (!m_clone->check_model(m_model))
if (!m_clone->check_model(m_model)) {
//IF_VERBOSE(0, display(verbose_stream()));
//IF_VERBOSE(0, display_watches(verbose_stream()));
//IF_VERBOSE(0, m_mc.display(verbose_stream()));
throw solver_exception("check model failed (for cloned solver)");
}
}
}
@ -1683,8 +1685,11 @@ namespace sat {
if (!w.is_binary_non_learned_clause())
continue;
literal l2 = w.get_literal();
if (l.index() > l2.index())
continue;
if (value_at(l2, m) != l_true) {
IF_VERBOSE(0, verbose_stream() << "failed binary: " << l << " " << l2 << "\n";);
IF_VERBOSE(0, verbose_stream() << "failed binary: " << l << " := " << value_at(l, m) << " " << l2 << " := " << value_at(l2, m) << "\n");
IF_VERBOSE(0, verbose_stream() << "elim l1: " << was_eliminated(l.var()) << " elim l2: " << was_eliminated(l2) << "\n");
TRACE("sat", m_mc.display(tout << "failed binary: " << l << " " << l2 << "\n"););
ok = false;
}
@ -3399,14 +3404,16 @@ namespace sat {
out.flush();
}
void solver::display_watches(std::ostream & out, literal lit) const {
sat::display_watch_list(out << lit << ": ", m_cls_allocator, get_wlist(lit)) << "\n";
}
void solver::display_watches(std::ostream & out) const {
unsigned l_idx = 0;
for (watch_list const& wlist : m_watches) {
literal l = to_literal(l_idx++);
out << l << ": ";
sat::display_watch_list(out, m_cls_allocator, wlist);
out << "\n";
if (!wlist.empty())
sat::display_watch_list(out << l << ": ", m_cls_allocator, wlist) << "\n";
}
}

1
src/sat/sat_solver.h
View file

@ -625,6 +625,7 @@ namespace sat {
bool check_invariant() const;
void display(std::ostream & out) const;
void display_watches(std::ostream & out) const;
void display_watches(std::ostream & out, literal lit) const;
void display_dimacs(std::ostream & out) const;
void display_wcnf(std::ostream & out, unsigned sz, literal const* lits, unsigned const* weights) const;
void display_assignment(std::ostream & out) const;