mirror of
https://github.com/Z3Prover/z3
synced 2025-04-28 19:35:50 +00:00
fix bug in PB constraint init_watch handling, adding transitive reduction, HLE, ULT,
Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>
This commit is contained in:
Nikolaj Bjorner
parent
427b5ef002
commit
018411bc58
10 changed files with 248 additions and 136 deletions
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@ -216,12 +216,12 @@ namespace sat {
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// ----------------------------
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// card
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bool ba_solver::init_watch(card& c, bool is_true) {
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bool ba_solver::init_watch(card& c) {
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clear_watch(c);
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literal root = c.lit();
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if (root != null_literal && root.sign() == is_true) {
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if (root != null_literal && value(root) == l_false) {
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c.negate();
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root.neg();
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root.neg();
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}
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if (root != null_literal) {
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if (!is_watched(root, c)) watch_literal(root, c);
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@ -352,7 +352,7 @@ namespace sat {
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IF_VERBOSE(100, display(verbose_stream() << "nullify tracking literal\n", p, true););
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SASSERT(lvl(p.lit()) == 0);
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nullify_tracking_literal(p);
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init_watch(p, true);
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init_watch(p);
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}
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SASSERT(p.lit() == null_literal || value(p.lit()) != l_false);
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@ -379,7 +379,7 @@ namespace sat {
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}
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else if (true_val == 0 && num_false == 0) {
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if (p.lit() == null_literal || value(p.lit()) == l_true) {
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init_watch(p, true);
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init_watch(p);
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}
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}
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else if (true_val >= p.k()) {
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@ -431,7 +431,7 @@ namespace sat {
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return;
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}
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else if (p.lit() == null_literal || value(p.lit()) == l_true) {
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init_watch(p, true);
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init_watch(p);
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}
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else {
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SASSERT(value(p.lit()) == l_undef);
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@ -510,13 +510,13 @@ namespace sat {
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// watch a prefix of literals, such that the slack of these is >= k
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bool ba_solver::init_watch(pb& p, bool is_true) {
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bool ba_solver::init_watch(pb& p) {
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clear_watch(p);
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if (p.lit() != null_literal && p.lit().sign() == is_true) {
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p.negate();
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if (p.lit() != null_literal && value(p.lit()) == l_false) {
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p.negate();
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}
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SASSERT(p.lit() == null_literal || value(p.lit()) == l_true);
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VERIFY(p.lit() == null_literal || value(p.lit()) == l_true);
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unsigned sz = p.size(), bound = p.k();
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// put the non-false literals into the head.
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@ -548,7 +548,7 @@ namespace sat {
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if (slack < bound) {
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literal lit = p[j].second;
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SASSERT(value(lit) == l_false);
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VERIFY(value(lit) == l_false);
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for (unsigned i = j + 1; i < sz; ++i) {
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if (lvl(lit) < lvl(p[i].second)) {
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lit = p[i].second;
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@ -826,7 +826,7 @@ namespace sat {
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SASSERT(p.well_formed());
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if (p.lit() == null_literal || value(p.lit()) == l_true) {
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init_watch(p, true);
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init_watch(p);
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}
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}
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}
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@ -909,9 +909,9 @@ namespace sat {
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return odd;
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}
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bool ba_solver::init_watch(xor& x, bool is_true) {
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bool ba_solver::init_watch(xor& x) {
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clear_watch(x);
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if (x.lit() != null_literal && x.lit().sign() == is_true) {
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if (x.lit() != null_literal && value(x.lit()) == l_false) {
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x.negate();
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}
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TRACE("ba", display(tout, x, true););
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@ -1566,7 +1566,7 @@ namespace sat {
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m_constraint_to_reinit.push_back(c);
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}
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else if (lit == null_literal) {
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init_watch(*c, true);
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init_watch(*c);
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}
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else {
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if (m_solver) m_solver->set_external(lit.var());
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@ -1577,12 +1577,12 @@ namespace sat {
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}
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bool ba_solver::init_watch(constraint& c, bool is_true) {
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bool ba_solver::init_watch(constraint& c) {
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if (inconsistent()) return false;
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switch (c.tag()) {
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case card_t: return init_watch(c.to_card(), is_true);
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case pb_t: return init_watch(c.to_pb(), is_true);
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case xor_t: return init_watch(c.to_xor(), is_true);
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case card_t: return init_watch(c.to_card());
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case pb_t: return init_watch(c.to_pb());
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case xor_t: return init_watch(c.to_xor());
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}
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UNREACHABLE();
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return false;
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@ -1642,7 +1642,7 @@ namespace sat {
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constraint& c = index2constraint(idx);
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TRACE("ba", tout << l << "\n";);
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if (c.lit() != null_literal && l.var() == c.lit().var()) {
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init_watch(c, !l.sign());
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init_watch(c);
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return true;
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}
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else if (c.lit() != null_literal && value(c.lit()) != l_true) {
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@ -2358,7 +2358,7 @@ namespace sat {
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unsigned sz = m_constraint_to_reinit_last_sz;
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for (unsigned i = sz; i < m_constraint_to_reinit.size(); ++i) {
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constraint* c = m_constraint_to_reinit[i];
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if (!init_watch(*c, true) && !s().at_base_lvl()) {
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if (!init_watch(*c) && !s().at_base_lvl()) {
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m_constraint_to_reinit[sz++] = c;
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}
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}
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@ -2677,7 +2677,7 @@ namespace sat {
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}
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else {
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if (c.lit() == null_literal || value(c.lit()) == l_true) {
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init_watch(c, true);
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init_watch(c);
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}
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SASSERT(c.lit() == null_literal || is_watched(c.lit(), c));
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SASSERT(c.well_formed());
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@ -2753,10 +2753,7 @@ namespace sat {
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recompile(c);
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}
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else {
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// review for potential incompleteness: if c.lit() == l_false, do propagations happen?
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if (c.lit() == null_literal || value(c.lit()) == l_true) {
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init_watch(c, true);
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}
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if (c.lit() == null_literal || value(c.lit()) != l_undef) init_watch(c);
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SASSERT(c.well_formed());
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}
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}
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@ -2870,7 +2867,6 @@ namespace sat {
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s().set_external(v);
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}
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}
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IF_VERBOSE(10, verbose_stream() << "non-external variables converted: " << ext << "\n";);
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return ext;
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}
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@ -2897,7 +2893,6 @@ namespace sat {
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++pure_literals;
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}
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}
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IF_VERBOSE(10, verbose_stream() << "pure literals converted: " << pure_literals << " " << inconsistent() << "\n";);
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return pure_literals;
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}
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@ -3119,7 +3114,7 @@ namespace sat {
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}
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}
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c2.set_size(c2.size() - 1);
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init_watch(c2, true);
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init_watch(c2);
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m_simplify_change = true;
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#endif
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}
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@ -296,7 +296,7 @@ namespace sat {
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void watch_literal(wliteral w, pb& p);
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bool is_watched(literal l, constraint const& c) const;
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void add_constraint(constraint* c);
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bool init_watch(constraint& c, bool is_true);
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bool init_watch(constraint& c);
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void init_watch(bool_var v);
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void clear_watch(constraint& c);
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lbool add_assign(constraint& c, literal l);
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@ -320,7 +320,7 @@ namespace sat {
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// cardinality
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bool init_watch(card& c, bool is_true);
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bool init_watch(card& c);
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lbool add_assign(card& c, literal lit);
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void clear_watch(card& c);
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void reset_coeffs();
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@ -334,7 +334,7 @@ namespace sat {
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// xor specific functionality
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void clear_watch(xor& x);
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bool init_watch(xor& x, bool is_true);
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bool init_watch(xor& x);
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bool parity(xor const& x, unsigned offset) const;
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lbool add_assign(xor& x, literal alit);
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void get_xor_antecedents(literal l, unsigned index, justification js, literal_vector& r);
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@ -345,7 +345,7 @@ namespace sat {
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// pb functionality
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unsigned m_a_max;
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bool init_watch(pb& p, bool is_true);
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bool init_watch(pb& p);
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lbool add_assign(pb& p, literal alit);
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void add_index(pb& p, unsigned index, literal lit);
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void clear_watch(pb& p);
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@ -59,7 +59,7 @@ namespace sat {
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}
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};
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void asymm_branch::process(clause_vector& clauses) {
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void asymm_branch::process(scc& scc, clause_vector& clauses) {
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int64 limit = -m_asymm_branch_limit;
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std::stable_sort(clauses.begin(), clauses.end(), clause_size_lt());
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m_counter -= clauses.size();
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@ -83,8 +83,9 @@ namespace sat {
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}
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s.checkpoint();
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clause & c = *(*it);
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if (!process(c))
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if (m_asymm_branch_sampled ? !process_sampled(scc, c) : !process(c)) {
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continue; // clause was removed
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}
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*it2 = *it;
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++it2;
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}
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@ -103,7 +104,7 @@ namespace sat {
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void asymm_branch::operator()(bool force) {
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++m_calls;
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if (m_calls <= 1)
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if (m_calls <= m_asymm_branch_delay)
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return;
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if (!m_asymm_branch && !m_asymm_branch_all)
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return;
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@ -118,9 +119,27 @@ namespace sat {
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TRACE("asymm_branch_detail", s.display(tout););
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report rpt(*this);
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svector<char> saved_phase(s.m_phase);
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m_counter = 0;
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process(s.m_clauses);
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m_counter = -m_counter;
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if (m_asymm_branch_sampled) {
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scc scc(s, m_params);
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while (true) {
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unsigned elim = m_elim_literals;
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scc.init_big(true);
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process(scc, s.m_clauses);
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process(scc, s.m_learned);
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s.propagate(false);
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if (s.m_inconsistent)
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break;
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std::cout << m_elim_literals - elim << "\n";
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if (m_elim_literals == elim)
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break;
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}
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}
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else {
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scc scc(s, m_params);
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m_counter = 0;
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process(scc, s.m_clauses);
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m_counter = -m_counter;
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}
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s.m_phase = saved_phase;
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m_asymm_branch_limit *= 2;
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if (m_asymm_branch_limit > UINT_MAX)
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@ -145,12 +164,6 @@ namespace sat {
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return true;
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}
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void asymm_branch::setup_big() {
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scc scc(s, m_params);
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vector<literal_vector> const& big = scc.get_big(true); // include learned binary clauses
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}
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struct asymm_branch::compare_left {
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scc& s;
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compare_left(scc& s): s(s) {}
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@ -206,19 +219,34 @@ namespace sat {
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right = right2;
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}
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}
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right = scc.get_right(m_neg[0]);
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for (unsigned i = 1; i < m_neg.size(); ++i) {
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literal lit = m_neg[i];
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int right2 = scc.get_right(lit);
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if (right > right2) {
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// ~first => ~lit
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m_to_delete.push_back(~lit);
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}
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else {
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right = right2;
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if (m_to_delete.empty()) {
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right = scc.get_right(m_neg[0]);
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for (unsigned i = 1; i < m_neg.size(); ++i) {
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literal lit = m_neg[i];
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int right2 = scc.get_right(lit);
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if (right > right2) {
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// ~first => ~lit
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m_to_delete.push_back(~lit);
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}
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else {
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right = right2;
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}
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}
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}
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if (!m_to_delete.empty()) {
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#if 0
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std::cout << "delete " << m_to_delete << "\n";
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std::cout << "pos\n";
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for (literal l : m_pos) {
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std::cout << l << ": " << scc.get_left(l) << " " << scc.get_right(l) << "\n";
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}
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std::cout << "neg\n";
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for (literal l : m_neg) {
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std::cout << l << ": " << scc.get_left(l) << " " << scc.get_right(l) << "\n";
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}
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std::cout << "\n";
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#endif
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unsigned j = 0;
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for (unsigned i = 0; i < c.size(); ++i) {
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if (!m_to_delete.contains(c[i])) {
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@ -282,13 +310,13 @@ namespace sat {
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break;
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}
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}
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new_sz = j;
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m_elim_literals += c.size() - new_sz;
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new_sz = j;
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// std::cout << "cleanup: " << c.id() << ": " << literal_vector(new_sz, c.begin()) << " delta: " << (c.size() - new_sz) << " " << skip_idx << " " << new_sz << "\n";
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return re_attach(scoped_d, c, new_sz);
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}
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bool asymm_branch::re_attach(scoped_detach& scoped_d, clause& c, unsigned new_sz) {
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m_elim_literals += c.size() - new_sz;
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switch(new_sz) {
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case 0:
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s.set_conflict(justification());
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@ -315,8 +343,9 @@ namespace sat {
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}
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}
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bool asymm_branch::process2(scc& scc, clause & c) {
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bool asymm_branch::process_sampled(scc& scc, clause & c) {
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scoped_detach scoped_d(s, c);
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sort(scc, c);
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if (uhte(scc, c)) {
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scoped_d.del_clause();
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return false;
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@ -372,6 +401,8 @@ namespace sat {
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void asymm_branch::updt_params(params_ref const & _p) {
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sat_asymm_branch_params p(_p);
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m_asymm_branch = p.asymm_branch();
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m_asymm_branch_delay = p.asymm_branch_delay();
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m_asymm_branch_sampled = p.asymm_branch_sampled();
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m_asymm_branch_limit = p.asymm_branch_limit();
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m_asymm_branch_all = p.asymm_branch_all();
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if (m_asymm_branch_limit > UINT_MAX)
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@ -39,6 +39,8 @@ namespace sat {
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// config
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bool m_asymm_branch;
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unsigned m_asymm_branch_delay;
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bool m_asymm_branch_sampled;
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bool m_asymm_branch_all;
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int64 m_asymm_branch_limit;
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@ -60,9 +62,9 @@ namespace sat {
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bool process(clause & c);
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bool process2(scc& scc, clause & c);
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bool process_sampled(scc& scc, clause & c);
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void process(clause_vector & c);
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void process(scc& scc, clause_vector & c);
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bool process_all(clause & c);
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@ -72,8 +74,6 @@ namespace sat {
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bool propagate_literal(clause const& c, literal l);
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void setup_big();
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public:
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asymm_branch(solver & s, params_ref const & p);
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@ -2,5 +2,7 @@ def_module_params(module_name='sat',
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class_name='sat_asymm_branch_params',
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export=True,
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params=(('asymm_branch', BOOL, True, 'asymmetric branching'),
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('asymm_branch.delay', UINT, 1, 'number of simplification rounds to wait until invoking asymmetric branch simplification'),
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('asymm_branch.sampled', BOOL, False, 'use sampling based asymmetric branching based on binary implication graph'),
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('asymm_branch.limit', UINT, 100000000, 'approx. maximum number of literals visited during asymmetric branching'),
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('asymm_branch.all', BOOL, False, 'asymmetric branching on all literals per clause')))
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@ -20,6 +20,7 @@ Notes:
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#include "sat/sat_solver.h"
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#include "sat/sat_extension.h"
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#include "sat/sat_lookahead.h"
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#include "sat/sat_scc.h"
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#include "util/union_find.h"
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namespace sat {
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@ -2304,15 +2305,86 @@ namespace sat {
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|||
|
||||
void lookahead::add_hyper_binary() {
|
||||
|
||||
unsigned num_lits = m_s.num_vars() * 2;
|
||||
|
||||
#if 0
|
||||
std::cout << "binary trail size: " << m_binary_trail.size() << "\n";
|
||||
std::cout << "Are windfalls still on the trail at base level?\n";
|
||||
unsigned num_lits = m_s.num_vars() * 2;
|
||||
#endif
|
||||
|
||||
unsigned disconnected1 = 0;
|
||||
unsigned disconnected2 = 0;
|
||||
|
||||
#if 1
|
||||
typedef std::pair<unsigned, unsigned> u_pair;
|
||||
hashtable<u_pair, pair_hash<unsigned_hash, unsigned_hash>, default_eq<u_pair> > imp;
|
||||
for (unsigned idx = 0; idx < num_lits; ++idx) {
|
||||
literal u = get_parent(to_literal(idx));
|
||||
if (null_literal != u) {
|
||||
for (watched const& w : m_s.m_watches[idx]) {
|
||||
if (!w.is_binary_clause()) continue;
|
||||
literal v = get_parent(w.get_literal());
|
||||
if (null_literal != v) {
|
||||
imp.insert(std::make_pair(u.index(), v.index()));
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
scc scc(m_s, m_s.m_params);
|
||||
scc.init_big(true);
|
||||
svector<std::pair<literal, literal>> candidates;
|
||||
|
||||
unsigned_vector bin_size(num_lits);
|
||||
for (unsigned idx : m_binary_trail) {
|
||||
bin_size[idx]++;
|
||||
}
|
||||
|
||||
for (unsigned idx = 0; idx < num_lits; ++idx) {
|
||||
literal u = to_literal(idx);
|
||||
if (u != get_parent(u)) continue;
|
||||
if (m_s.was_eliminated(u.var())) continue;
|
||||
literal_vector const& lits = m_binary[idx];
|
||||
for (unsigned sz = bin_size[idx]; sz > 0; --sz) {
|
||||
literal v = lits[lits.size() - sz];
|
||||
if (v != get_parent(v)) continue;
|
||||
if (m_s.was_eliminated(v.var())) continue;
|
||||
if (imp.contains(std::make_pair(u.index(), v.index()))) continue;
|
||||
if (scc.reaches(u, v)) continue;
|
||||
candidates.push_back(std::make_pair(u, v));
|
||||
}
|
||||
}
|
||||
for (unsigned i = 0; i < 5; ++i) {
|
||||
scc.init_big(true);
|
||||
unsigned k = 0;
|
||||
union_find_default_ctx ufctx;
|
||||
union_find<union_find_default_ctx> uf(ufctx);
|
||||
for (unsigned i = 0; i < num_lits; ++i) uf.mk_var();
|
||||
for (unsigned j = 0; j < candidates.size(); ++j) {
|
||||
literal u = candidates[j].first;
|
||||
literal v = candidates[j].second;
|
||||
if (!scc.reaches(u, v)) {
|
||||
if (uf.find(u.index()) != uf.find(v.index())) {
|
||||
++disconnected1;
|
||||
uf.merge(u.index(), v.index());
|
||||
uf.merge((~u).index(), (~v).index());
|
||||
m_s.mk_clause(~u, v, true);
|
||||
}
|
||||
else {
|
||||
candidates[k] = candidates[j];
|
||||
++k;
|
||||
}
|
||||
}
|
||||
}
|
||||
std::cout << candidates.size() << " -> " << k << "\n";
|
||||
if (k == candidates.size()) break;
|
||||
candidates.shrink(k);
|
||||
}
|
||||
|
||||
std::cout << "candidates: " << candidates.size() << "\n";
|
||||
|
||||
#endif
|
||||
|
||||
#if 0
|
||||
union_find_default_ctx ufctx;
|
||||
union_find<union_find_default_ctx> uf(ufctx);
|
||||
for (unsigned i = 0; i < num_lits; ++i) uf.mk_var();
|
||||
|
|
@ -2329,21 +2401,25 @@ namespace sat {
|
|||
}
|
||||
}
|
||||
|
||||
unsigned disconnected = 0;
|
||||
for (unsigned i = 0; i < m_binary.size(); ++i) {
|
||||
literal u = to_literal(i);
|
||||
if (u == get_parent(u)) {
|
||||
if (u == get_parent(u) && !m_s.was_eliminated(u.var())) {
|
||||
for (literal v : m_binary[i]) {
|
||||
if (v == get_parent(v) && uf.find(u.index()) != uf.find(v.index())) {
|
||||
++disconnected;
|
||||
if (v == get_parent(v) &&
|
||||
!m_s.was_eliminated(v.var()) &&
|
||||
uf.find(u.index()) != uf.find(v.index())) {
|
||||
++disconnected2;
|
||||
uf.merge(u.index(), v.index());
|
||||
m_s.mk_clause(~u, v, true);
|
||||
// m_s.mk_clause(~u, v, true);
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
IF_VERBOSE(10, verbose_stream() << "(sat-lookahead :bca " << disconnected << ")\n";);
|
||||
m_stats.m_bca += disconnected;
|
||||
#endif
|
||||
|
||||
IF_VERBOSE(10, verbose_stream() << "(sat-lookahead :bca " << disconnected1 << " " << disconnected2 << ")\n";);
|
||||
//IF_VERBOSE(10, verbose_stream() << "(sat-lookahead :bca " << disconnected << ")\n";);
|
||||
//m_stats.m_bca += disconnected;
|
||||
}
|
||||
|
||||
void lookahead::normalize_parents() {
|
||||
|
|
|
|||
|
|
@ -234,17 +234,7 @@ namespace sat {
|
|||
return to_elim.size();
|
||||
}
|
||||
|
||||
// shuffle vertices to obtain different DAG traversal each time
|
||||
void scc::shuffle(literal_vector& lits) {
|
||||
unsigned sz = lits.size();
|
||||
if (sz > 1) {
|
||||
for (unsigned i = sz; i-- > 0; ) {
|
||||
std::swap(lits[i], lits[m_rand(i+1)]);
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
vector<literal_vector> const& scc::get_big(bool learned) {
|
||||
void scc::init_big(bool learned) {
|
||||
unsigned num_lits = m_solver.num_vars() * 2;
|
||||
m_dag.reset();
|
||||
m_roots.reset();
|
||||
|
|
@ -263,53 +253,21 @@ namespace sat {
|
|||
edges.push_back(v);
|
||||
}
|
||||
}
|
||||
shuffle(edges);
|
||||
shuffle<literal>(edges.size(), edges.c_ptr(), m_rand);
|
||||
}
|
||||
return m_dag;
|
||||
init_dfs_num(learned);
|
||||
}
|
||||
|
||||
void scc::get_dfs_num(bool learned) {
|
||||
unsigned num_lits = m_solver.num_vars() * 2;
|
||||
SASSERT(m_left.size() == num_lits);
|
||||
SASSERT(m_right.size() == num_lits);
|
||||
literal_vector todo;
|
||||
// retrieve literals that have no predecessors
|
||||
for (unsigned l_idx = 0; l_idx < num_lits; l_idx++) {
|
||||
literal u(to_literal(l_idx));
|
||||
if (m_roots[u.index()]) todo.push_back(u);
|
||||
}
|
||||
shuffle(todo);
|
||||
int dfs_num = 0;
|
||||
while (!todo.empty()) {
|
||||
literal u = todo.back();
|
||||
int& d = m_left[u.index()];
|
||||
// already visited
|
||||
if (d > 0) {
|
||||
if (m_right[u.index()] < 0) {
|
||||
m_right[u.index()] = dfs_num;
|
||||
}
|
||||
todo.pop_back();
|
||||
}
|
||||
// visited as child:
|
||||
else if (d < 0) {
|
||||
d = -d;
|
||||
for (literal v : m_dag[u.index()]) {
|
||||
if (m_left[v.index()] == 0) {
|
||||
m_left[v.index()] = - d - 1;
|
||||
m_root[v.index()] = m_root[u.index()];
|
||||
m_parent[v.index()] = u;
|
||||
todo.push_back(v);
|
||||
}
|
||||
}
|
||||
}
|
||||
// new root.
|
||||
else {
|
||||
d = --dfs_num;
|
||||
}
|
||||
}
|
||||
}
|
||||
struct scc::pframe {
|
||||
literal m_parent;
|
||||
literal m_child;
|
||||
pframe(literal p, literal c):
|
||||
m_parent(p), m_child(c) {}
|
||||
literal child() const { return m_child; }
|
||||
literal parent() const { return m_parent; }
|
||||
};
|
||||
|
||||
unsigned scc::reduce_tr(bool learned) {
|
||||
void scc::init_dfs_num(bool learned) {
|
||||
unsigned num_lits = m_solver.num_vars() * 2;
|
||||
m_left.reset();
|
||||
m_right.reset();
|
||||
|
|
@ -317,11 +275,61 @@ namespace sat {
|
|||
m_parent.reset();
|
||||
m_left.resize(num_lits, 0);
|
||||
m_right.resize(num_lits, -1);
|
||||
m_root.resize(num_lits, null_literal);
|
||||
m_parent.resize(num_lits, null_literal);
|
||||
for (unsigned i = 0; i < num_lits; ++i) {
|
||||
m_root[i] = to_literal(i);
|
||||
m_parent[i] = to_literal(i);
|
||||
}
|
||||
get_dfs_num(learned);
|
||||
svector<pframe> todo;
|
||||
// retrieve literals that have no predecessors
|
||||
for (unsigned l_idx = 0; l_idx < num_lits; l_idx++) {
|
||||
literal u(to_literal(l_idx));
|
||||
if (m_roots[u.index()]) {
|
||||
todo.push_back(pframe(null_literal, u));
|
||||
}
|
||||
}
|
||||
shuffle<pframe>(todo.size(), todo.c_ptr(), m_rand);
|
||||
int dfs_num = 0;
|
||||
while (!todo.empty()) {
|
||||
literal u = todo.back().child();
|
||||
if (m_left[u.index()] > 0) {
|
||||
// already visited
|
||||
if (m_right[u.index()] < 0) {
|
||||
m_right[u.index()] = ++dfs_num;
|
||||
}
|
||||
todo.pop_back();
|
||||
}
|
||||
else {
|
||||
SASSERT(m_left[u.index()] == 0);
|
||||
m_left[u.index()] = ++dfs_num;
|
||||
for (literal v : m_dag[u.index()]) {
|
||||
if (m_left[v.index()] == 0) {
|
||||
todo.push_back(pframe(u, v));
|
||||
}
|
||||
}
|
||||
literal p = todo.back().parent();
|
||||
if (p != null_literal) {
|
||||
m_root[u.index()] = m_root[p.index()];
|
||||
m_parent[u.index()] = p;
|
||||
}
|
||||
}
|
||||
}
|
||||
for (unsigned i = 0; i < num_lits; ++i) {
|
||||
if (m_right[i] < 0) {
|
||||
VERIFY(m_left[i] == 0);
|
||||
m_left[i] = ++dfs_num;
|
||||
m_right[i] = ++dfs_num;
|
||||
}
|
||||
}
|
||||
for (unsigned i = 0; i < num_lits; ++i) {
|
||||
VERIFY(m_left[i] < m_right[i]);
|
||||
}
|
||||
}
|
||||
|
||||
unsigned scc::reduce_tr(bool learned) {
|
||||
unsigned num_lits = m_solver.num_vars() * 2;
|
||||
init_big(learned);
|
||||
unsigned idx = 0;
|
||||
unsigned elim = m_num_elim_bin;
|
||||
for (watch_list & wlist : m_solver.m_watches) {
|
||||
|
|
@ -333,7 +341,7 @@ namespace sat {
|
|||
watched& w = *it;
|
||||
if (learned ? w.is_binary_learned_clause() : w.is_binary_unblocked_clause()) {
|
||||
literal v = w.get_literal();
|
||||
if (m_left[u.index()] + 1 < m_left[v.index()]) {
|
||||
if (reaches(u, v) && u != get_parent(v)) {
|
||||
++m_num_elim_bin;
|
||||
}
|
||||
else {
|
||||
|
|
|
|||
|
|
@ -44,10 +44,13 @@ namespace sat {
|
|||
svector<int> m_left, m_right;
|
||||
literal_vector m_root, m_parent;
|
||||
|
||||
void shuffle(literal_vector& lits);
|
||||
void reduce_tr();
|
||||
unsigned reduce_tr(bool learned);
|
||||
|
||||
void init_dfs_num(bool learned);
|
||||
|
||||
struct pframe;
|
||||
|
||||
public:
|
||||
|
||||
scc(solver & s, params_ref const & p);
|
||||
|
|
@ -60,17 +63,14 @@ namespace sat {
|
|||
void reset_statistics();
|
||||
|
||||
/*
|
||||
\brief retrieve binary implication graph
|
||||
\brief create binary implication graph and associated data-structures to check transitivity.
|
||||
*/
|
||||
vector<literal_vector> const& get_big(bool learned);
|
||||
|
||||
void init_big(bool learned);
|
||||
int get_left(literal l) const { return m_left[l.index()]; }
|
||||
int get_right(literal l) const { return m_right[l.index()]; }
|
||||
literal get_parent(literal l) const { return m_parent[l.index()]; }
|
||||
literal get_root(literal l) const { return m_root[l.index()]; }
|
||||
|
||||
void get_dfs_num(bool learned);
|
||||
|
||||
bool reaches(literal u, literal v) const { return m_left[u.index()] < m_left[v.index()] && m_right[v.index()] < m_right[u.index()]; }
|
||||
};
|
||||
};
|
||||
|
||||
|
|
|
|||
|
|
@ -2,7 +2,7 @@ def_module_params(module_name='sat',
|
|||
class_name='sat_simplifier_params',
|
||||
export=True,
|
||||
params=(('elim_blocked_clauses', BOOL, False, 'eliminate blocked clauses'),
|
||||
('abce', BOOL, BOOL, False, 'eliminate blocked clauses using asymmmetric literals'),
|
||||
('abce', BOOL, False, 'eliminate blocked clauses using asymmmetric literals'),
|
||||
('cce', BOOL, False, 'eliminate covered clauses'),
|
||||
('acce', BOOL, False, 'eliminate covered clauses using asymmetric added literals'),
|
||||
('elim_blocked_clauses_at', UINT, 2, 'eliminate blocked clauses only once at the given simplification round'),
|
||||
|
|
|
|||
|
|
@ -191,7 +191,7 @@ namespace sat {
|
|||
// Misc
|
||||
//
|
||||
// -----------------------
|
||||
void updt_params(params_ref const & p);
|
||||
void updt_params(params_ref const & p);
|
||||
static void collect_param_descrs(param_descrs & d);
|
||||
|
||||
void collect_statistics(statistics & st) const;
|
||||
|
|
|
|||
Loading…
Add table
Add a link
Reference in a new issue