mirror of
https://github.com/Z3Prover/z3
synced 2025-04-28 19:35:50 +00:00
update conflict resolution for cardinality case
Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>
This commit is contained in:
Nikolaj Bjorner
parent
e36eba1168
commit
cb6c6332b3
6 changed files with 189 additions and 328 deletions
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@ -264,7 +264,7 @@ br_status pb_rewriter::mk_app_core(func_decl * f, unsigned num_args, expr * cons
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result = m_util.mk_eq(sz, m_coeffs.c_ptr(), m_args.c_ptr(), k);
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}
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}
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else if (all_unit && k.is_one()) {
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else if (all_unit && k.is_one() && sz < 10) {
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result = mk_or(m, sz, m_args.c_ptr());
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}
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else if (all_unit && k == rational(sz)) {
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@ -3342,10 +3342,6 @@ namespace smt {
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bool context::restart(lbool& status, unsigned curr_lvl) {
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std::cout << "restart: " << m_lemmas.size() << "\n";
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for (unsigned i = 0; i < m_lemmas.size(); ++i) {
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display_clause(std::cout, m_lemmas[i]); std::cout << "\n";
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}
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if (m_last_search_failure != OK) {
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if (status != l_false) {
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@ -599,21 +599,20 @@ namespace smt {
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break;
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case b_justification::BIN_CLAUSE: {
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literal l2 = j.get_literal();
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out << "bin-clause ";
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display_literal(out, l2);
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out << "bin-clause " << l2;
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break;
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}
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case b_justification::CLAUSE: {
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clause * cls = j.get_clause();
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out << "clause ";
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if (cls) display_literals_verbose(out, cls->get_num_literals(), cls->begin_literals());
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if (cls) out << literal_vector(cls->get_num_literals(), cls->begin_literals());
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break;
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}
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case b_justification::JUSTIFICATION: {
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out << "justification ";
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literal_vector lits;
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const_cast<conflict_resolution&>(*m_conflict_resolution).justification2literals(j.get_justification(), lits);
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display_literals_verbose(out, lits.size(), lits.c_ptr());
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out << lits;
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break;
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}
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default:
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@ -1343,6 +1343,7 @@ namespace smt {
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cls->swap_lits(1, w2_idx);
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TRACE("mk_th_lemma", display_clause(tout, cls); tout << "\n";);
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}
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// display_clause(std::cout, cls); std::cout << "\n";
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m_lemmas.push_back(cls);
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add_watch_literal(cls, 0);
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add_watch_literal(cls, 1);
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@ -65,9 +65,6 @@ namespace smt {
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};
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};
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const unsigned theory_pb::null_index = UINT_MAX;
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unsigned theory_pb::arg_t::get_hash() const {
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return get_composite_hash<arg_t, arg_t::kind_hash, arg_t::child_hash>(*this, size());
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}
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@ -275,7 +272,7 @@ namespace smt {
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// conflict
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if (0 != index && ctx.get_assignment(m_args[0]) == l_false) {
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TRACE("pb", tout << "conflict " << m_args[0] << " " << lit << "\n";);
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set_conflict(th, m_args[0], lit);
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set_conflict(th, lit);
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return l_false;
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}
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@ -289,6 +286,7 @@ namespace smt {
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}
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SASSERT(m_args[0] == lit);
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literal_vector lits;
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lits.push_back(m_lit);
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lits.push_back(~lit);
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for (unsigned i = m_bound + 1; i < sz; ++i) {
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SASSERT(ctx.get_assignment(m_args[i]) == l_false);
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@ -303,7 +301,7 @@ namespace smt {
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break;
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case l_false:
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TRACE("pb", tout << "conflict: " << lit << " " << lit2 << "\n";);
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set_conflict(th, lit, lit2);
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set_conflict(th, lit2);
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return l_false;
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case l_undef:
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SASSERT(validate_assign(th, lits, lit2));
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@ -314,15 +312,26 @@ namespace smt {
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return l_true;
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}
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/**
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\brief The conflict clause position for cardinality constraint have the following properties:
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0. The position for the literal corresponding to the cardinality constraint.
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1. The literal at position 0 of the cardinality constraint.
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2. The asserting literal.
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3. .. the remaining false literals.
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*/
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void theory_pb::card::set_conflict(theory_pb& th, literal l1, literal l2) {
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void theory_pb::card::set_conflict(theory_pb& th, literal l) {
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SASSERT(validate_conflict(th));
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context& ctx = th.get_context();
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literal l0 = m_args[0];
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literal_vector lits;
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SASSERT(ctx.get_assignment(l1) == l_false);
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SASSERT(ctx.get_assignment(l2) == l_false);
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lits.push_back(l1);
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lits.push_back(l2);
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SASSERT(ctx.get_assignment(l0) == l_false);
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SASSERT(ctx.get_assignment(l) == l_false);
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SASSERT(ctx.get_assignment(lit()) == l_true);
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lits.push_back(~lit());
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lits.push_back(l0);
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lits.push_back(l);
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unsigned sz = size();
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for (unsigned i = m_bound + 1; i < sz; ++i) {
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SASSERT(ctx.get_assignment(m_args[i]) == l_false);
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@ -369,7 +378,20 @@ namespace smt {
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}
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// j is the number of non-false, sz - j the number of false.
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if (j < m_bound) {
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set_conflict(th, m_args[m_bound], m_args[m_bound-1]);
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std::swap(m_args[0], m_args[m_bound-1]);
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//
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// we need the assignment level of the asserting literal to be maximal.
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// such that conflict resolution can use the asserting literal as a starting
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// point.
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if (ctx.get_assign_level(m_args[0]) > ctx.get_assign_level(m_args[m_bound])) {
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std::swap(m_args[0], m_args[m_bound]);
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}
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for (i = m_bound + 1; i < sz; ++i) {
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if (ctx.get_assign_level(m_args[i]) > ctx.get_assign_level(m_args[m_bound])) {
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std::swap(m_args[i], m_args[m_bound]);
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}
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}
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set_conflict(th, m_args[m_bound]);
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}
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else if (j == m_bound) {
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literal_vector lits(size() - m_bound, m_args.c_ptr() + m_bound);
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@ -557,7 +579,6 @@ namespace smt {
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}
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row r = m_simplex.get_infeasible_row();
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// m_simplex.display_row(std::cout, r, true);
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mpz const& coeff = m_simplex.get_base_coeff(r);
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bool_var base_var = m_simplex.get_base_var(r);
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SASSERT(m_simplex.below_lower(base_var) || m_simplex.above_upper(base_var));
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@ -1086,6 +1107,7 @@ namespace smt {
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if (proofs_enabled()) {
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js = alloc(theory_lemma_justification, get_id(), ctx, lits.size(), lits.c_ptr());
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}
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resolve_conflict(c, lits);
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c.inc_propagations(*this);
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ctx.mk_clause(lits.size(), lits.c_ptr(), js, CLS_AUX_LEMMA, 0);
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}
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@ -1094,7 +1116,7 @@ namespace smt {
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c.inc_propagations(*this);
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m_stats.m_num_propagations++;
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context& ctx = get_context();
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TRACE("pb", tout << "#prop:" << c.num_propagations() << " - " << lits << " " << c.lit() << " => " << l << "\n";);
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TRACE("pb", tout << "#prop: " << c.num_propagations() << " - " << lits << " " << c.lit() << " => " << l << "\n";);
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ctx.assign(l, ctx.mk_justification(
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card_justification(
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@ -1488,7 +1510,6 @@ namespace smt {
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bool removed = false;
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context& ctx = get_context();
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ineq& c = *watch[watch_index];
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//display(std::cout << v << " ", c, true);
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unsigned w = c.find_lit(v, 0, c.watch_size());
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SASSERT(ctx.get_assignment(c.lit()) == l_true);
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SASSERT(is_true == c.lit(w).sign());
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@ -1856,229 +1877,128 @@ namespace smt {
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inc_propagations(c);
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m_stats.m_num_conflicts++;
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context& ctx = get_context();
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#if 0
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if (m_stats.m_num_conflicts == 1000) {
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display(std::cout);
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}
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#endif
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TRACE("pb", tout << "#prop:" << c.m_num_propagations << " - ";
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for (unsigned i = 0; i < lits.size(); ++i) {
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tout << lits[i] << " ";
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}
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tout << "\n";
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display(tout, c, true););
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TRACE("pb", tout << "#prop:" << c.m_num_propagations << " - " << lits << "\n";
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display(tout, c, true););
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justification* js = 0;
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if (m_conflict_frequency == 0 || (m_conflict_frequency -1 == (c.m_num_propagations % m_conflict_frequency))) {
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resolve_conflict(c);
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}
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if (proofs_enabled()) {
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js = alloc(theory_lemma_justification, get_id(), ctx, lits.size(), lits.c_ptr());
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}
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TRACE("pb", tout << lits << "\n";);
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ctx.mk_clause(lits.size(), lits.c_ptr(), js, CLS_AUX_LEMMA, 0);
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}
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void theory_pb::set_mark(bool_var v, unsigned idx) {
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SASSERT(v != null_bool_var);
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if (v >= static_cast<bool_var>(m_conseq_index.size())) {
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m_conseq_index.resize(v+1, null_index);
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int theory_pb::get_coeff(bool_var v) const {
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return m_coeffs.get(v, 0);
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}
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void theory_pb::reset_coeffs() {
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for (unsigned i = 0; i < m_active_coeffs.size(); ++i) {
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m_coeffs[m_active_coeffs[i]] = 0;
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}
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SASSERT(!is_marked(v) || m_conseq_index[v] == idx);
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m_marked.push_back(v);
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m_conseq_index[v] = idx;
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m_active_coeffs.reset();
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}
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bool theory_pb::is_marked(bool_var v) const {
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return
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(v < static_cast<bool_var>(m_conseq_index.size())) &&
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(m_conseq_index[v] != null_index);
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}
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void theory_pb::unset_mark(bool_var v) {
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SASSERT(v != null_bool_var);
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if (v < static_cast<bool_var>(m_conseq_index.size())) {
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m_conseq_index[v] = null_index;
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}
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}
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void theory_pb::unset_marks() {
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for (unsigned i = 0; i < m_marked.size(); ++i) {
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unset_mark(m_marked[i]);
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}
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m_marked.reset();
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}
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void theory_pb::process_antecedent(literal l, numeral coeff) {
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void theory_pb::process_antecedent(literal l, int offset) {
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context& ctx = get_context();
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SASSERT(ctx.get_assignment(l) == l_false);
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bool_var v = l.var();
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unsigned lvl = ctx.get_assign_level(v);
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if (ctx.get_assignment(l) != l_false) {
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m_lemma.m_k -= coeff;
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if (m_learn_complements && is_marked(v)) {
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SASSERT(ctx.get_assignment(l) == l_true);
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numeral& lcoeff = m_lemma[m_conseq_index[v]].second;
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lcoeff -= coeff;
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if (!lcoeff.is_pos()) {
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// perhaps let lemma simplification change coefficient
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// when negative?
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remove_from_lemma(m_conseq_index[v]);
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}
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}
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TRACE("pb", tout << l << " " << ctx.is_marked(v) << " " << m_conflict_lvl << " " << ctx.get_base_level() << "\n";);
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if (lvl > ctx.get_base_level() && !ctx.is_marked(v) && lvl == m_conflict_lvl) {
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ctx.set_mark(v);
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++m_num_marks;
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}
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else if (lvl > ctx.get_base_level()) {
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if (is_marked(v)) {
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m_lemma[m_conseq_index[v]].second += coeff;
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SASSERT(m_lemma[m_conseq_index[v]].second.is_pos());
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}
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else {
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if (lvl == m_conflict_lvl) {
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TRACE("pb", tout << "add mark: " << l << " " << coeff << "\n";);
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++m_num_marks;
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}
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set_mark(v, m_lemma.size());
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m_lemma.push_back(std::make_pair(l, coeff));
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}
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TRACE("pb_verbose", tout
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<< "ante: " << m_lemma.lit(m_conseq_index[v]) << "*"
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<< m_lemma.coeff(m_conseq_index[v]) << " " << lvl << "\n";);
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if (lvl > ctx.get_base_level()) {
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inc_coeff(l, offset);
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}
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}
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void theory_pb::process_ineq(ineq& c, literal conseq, numeral coeff1) {
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//
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// Create CUT.
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//
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//
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// . find coeff2
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// . find lcm of coefficients to conseq.
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// . multiply m_lemma by lcm/coeff coefficient to align.
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// . create lcm/coeff_2 to multiply on this side.
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// . cut resolve constraints.
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//
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void theory_pb::process_card(card& c, int offset) {
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context& ctx = get_context();
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numeral coeff2 = (conseq==null_literal)?numeral::one():numeral::zero();
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for (unsigned i = 0; i < c.size(); ++i) {
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if (c.lit(i) == conseq) {
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coeff2 = c.coeff(i);
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break;
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}
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process_antecedent(c.lit(0), offset);
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for (unsigned i = c.k() + 1; i < c.size(); ++i) {
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process_antecedent(c.lit(i), offset);
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}
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SASSERT(coeff2.is_pos());
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numeral lc = lcm(coeff1, coeff2);
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numeral g = lc/coeff1;
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SASSERT(g.is_int());
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if (g > numeral::one()) {
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for (unsigned i = 0; i < m_lemma.size(); ++i) {
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m_lemma[i].second *= g;
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}
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m_lemma.m_k *= g;
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for (unsigned i = 1; i <= c.k(); ++i) {
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inc_coeff(c.lit(i), offset);
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}
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g = lc/coeff2;
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SASSERT(g.is_int());
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m_lemma.m_k += g*c.k();
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for (unsigned i = 0; i < c.size(); ++i) {
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process_antecedent(c.lit(i), g*c.coeff(i));
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}
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SASSERT(ctx.get_assignment(c.lit()) == l_true);
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if (ctx.get_assign_level(c.lit()) > ctx.get_base_level()) {
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m_ineq_literals.push_back(c.lit());
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m_antecedents.push_back(c.lit());
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}
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SASSERT(ctx.get_assignment(c.lit()) == l_true);
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}
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void theory_pb::inc_coeff(literal l, int offset) {
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if (l.sign()) {
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m_bound -= offset;
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}
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bool_var v = l.var();
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SASSERT(v != null_bool_var);
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if (static_cast<bool_var>(m_coeffs.size()) <= v) {
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m_coeffs.resize(v + 1, 0);
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}
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if (m_coeffs[v] == 0) {
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m_active_coeffs.push_back(v);
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}
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int inc = l.sign() ? -offset : offset;
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m_coeffs[v] += inc;
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}
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//
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// modeled after sat_solver/smt_context
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//
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bool theory_pb::resolve_conflict(ineq& c) {
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bool theory_pb::resolve_conflict(card& c, literal_vector const& confl) {
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if (!c.is_ge()) {
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return false;
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}
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TRACE("pb", display(tout, c, true););
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TRACE("pb", display(tout, c, true); get_context().display(tout););
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bool_var v;
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literal conseq;
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context& ctx = get_context();
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unsigned& lvl = m_conflict_lvl = 0;
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for (unsigned i = 0; i < c.size(); ++i) {
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if (ctx.get_assignment(c.lit(i)) == l_false) {
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lvl = std::max(lvl, ctx.get_assign_level(c.lit(i)));
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}
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m_conflict_lvl = 0;
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for (unsigned i = 0; i < confl.size(); ++i) {
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literal lit = confl[i];
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SASSERT(ctx.get_assignment(lit) == l_false);
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m_conflict_lvl = std::max(m_conflict_lvl, ctx.get_assign_level(lit));
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}
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if (lvl < ctx.get_assign_level(c.lit()) || lvl == ctx.get_base_level()) {
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if (m_conflict_lvl < ctx.get_assign_level(c.lit()) || m_conflict_lvl == ctx.get_base_level()) {
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return false;
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}
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unset_marks();
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reset_coeffs();
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m_num_marks = 0;
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m_lemma.reset();
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m_lemma.m_k.reset();
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m_ineq_literals.reset();
|
||||
process_ineq(c, null_literal, numeral::one()); // add consequent to lemma.
|
||||
m_bound = c.k();
|
||||
m_antecedents.reset();
|
||||
literal_vector ante;
|
||||
|
||||
process_card(c, 1);
|
||||
|
||||
// point into stack of assigned literals
|
||||
literal_vector const& lits = ctx.assigned_literals();
|
||||
SASSERT(!lits.empty());
|
||||
unsigned idx = lits.size()-1;
|
||||
|
||||
b_justification js;
|
||||
literal conseq = ~confl[2];
|
||||
|
||||
while (m_num_marks > 0) {
|
||||
|
||||
TRACE("pb_verbose", display(tout << "lemma ", m_lemma););
|
||||
v = conseq.var();
|
||||
TRACE("pb", display_resolved_lemma(tout << conseq << "\n"););
|
||||
|
||||
lbool is_sat = m_lemma.normalize(false);
|
||||
if (is_sat == l_false) {
|
||||
break;
|
||||
}
|
||||
if (is_sat == l_true) {
|
||||
IF_VERBOSE(0, verbose_stream() << "lemma already evaluated\n";);
|
||||
TRACE("pb", tout << "lemma already evaluated\n";);
|
||||
return false;
|
||||
}
|
||||
TRACE("pb", display(tout, m_lemma););
|
||||
SASSERT(m_lemma.well_formed());
|
||||
|
||||
//
|
||||
// find the next marked variable in the assignment stack
|
||||
//
|
||||
do {
|
||||
conseq = lits[idx];
|
||||
v = conseq.var();
|
||||
--idx;
|
||||
int offset = get_coeff(v);
|
||||
|
||||
if (offset == 0) {
|
||||
goto process_next_resolvent;
|
||||
}
|
||||
while (!is_marked(v) && idx > 0);
|
||||
if (idx == 0 && !is_marked(v)) {
|
||||
//
|
||||
// Yes, this can (currently) happen because
|
||||
// the decisions for performing unit propagation
|
||||
// are made asynchronously.
|
||||
// In other words, PB unit propagation does not follow the
|
||||
// same order as the assignment stack.
|
||||
// It is not a correctness bug but causes to miss lemmas.
|
||||
//
|
||||
IF_VERBOSE(12, display_resolved_lemma(verbose_stream()););
|
||||
TRACE("pb", display_resolved_lemma(tout););
|
||||
return false;
|
||||
else if (offset < 0) {
|
||||
offset = -offset;
|
||||
}
|
||||
|
||||
js = ctx.get_justification(v);
|
||||
|
||||
TRACE("pb", tout << "conseq: " << conseq << "\n";);
|
||||
|
||||
unsigned conseq_index = m_conseq_index[v];
|
||||
numeral conseq_coeff = m_lemma.coeff(conseq_index);
|
||||
inc_coeff(conseq, offset);
|
||||
|
||||
TRACE("pb", display(tout, m_lemma, true);
|
||||
tout << "conseq: " << conseq << " at index: " << conseq_index << "\n";);
|
||||
|
||||
SASSERT(~conseq == m_lemma.lit(conseq_index));
|
||||
|
||||
remove_from_lemma(conseq_index);
|
||||
|
||||
b_justification js = ctx.get_justification(v);
|
||||
m_bound += offset;
|
||||
|
||||
//
|
||||
// Resolve selected conseq with antecedents.
|
||||
|
|
@ -2092,109 +2012,68 @@ namespace smt {
|
|||
if (cjs && !is_proof_justification(*cjs)) {
|
||||
TRACE("pb", tout << "skipping justification for clause over: " << conseq << " "
|
||||
<< typeid(*cjs).name() << "\n";);
|
||||
m_ineq_literals.push_back(conseq);
|
||||
break;
|
||||
}
|
||||
unsigned num_lits = cls.get_num_literals();
|
||||
if (cls.get_literal(0) == conseq) {
|
||||
process_antecedent(cls.get_literal(1), conseq_coeff);
|
||||
process_antecedent(cls.get_literal(1), offset);
|
||||
}
|
||||
else {
|
||||
SASSERT(cls.get_literal(1) == conseq);
|
||||
process_antecedent(cls.get_literal(0), conseq_coeff);
|
||||
process_antecedent(cls.get_literal(0), offset);
|
||||
}
|
||||
for (unsigned i = 2; i < num_lits; ++i) {
|
||||
process_antecedent(cls.get_literal(i), conseq_coeff);
|
||||
process_antecedent(cls.get_literal(i), offset);
|
||||
}
|
||||
TRACE("pb", for (unsigned i = 0; i < num_lits; ++i) tout << cls.get_literal(i) << " "; tout << "\n";);
|
||||
TRACE("pb", tout << literal_vector(cls.get_num_literals(), cls.begin_literals()) << "\n";);
|
||||
break;
|
||||
}
|
||||
case b_justification::BIN_CLAUSE:
|
||||
process_antecedent(~js.get_literal(), conseq_coeff);
|
||||
process_antecedent(~js.get_literal(), offset);
|
||||
TRACE("pb", tout << "binary: " << js.get_literal() << "\n";);
|
||||
break;
|
||||
case b_justification::AXIOM:
|
||||
if (ctx.get_assign_level(v) > ctx.get_base_level()) {
|
||||
m_ineq_literals.push_back(conseq);
|
||||
}
|
||||
TRACE("pb", tout << "axiom " << conseq << "\n";);
|
||||
break;
|
||||
case b_justification::JUSTIFICATION: {
|
||||
justification* j = js.get_justification();
|
||||
pb_justification* pbj = 0;
|
||||
card_justification* pbj = 0;
|
||||
|
||||
if (!conseq.sign() && j->get_from_theory() == get_id()) {
|
||||
pbj = dynamic_cast<pb_justification*>(j);
|
||||
if (j->get_from_theory() == get_id()) {
|
||||
pbj = dynamic_cast<card_justification*>(j);
|
||||
}
|
||||
if (pbj && pbj->get_ineq().is_eq()) {
|
||||
// only resolve >= that are positive consequences.
|
||||
pbj = 0;
|
||||
}
|
||||
if (pbj && pbj->get_ineq().lit() == conseq) {
|
||||
// can't resolve against literal representing inequality.
|
||||
pbj = 0;
|
||||
}
|
||||
if (pbj) {
|
||||
// weaken the lemma and resolve.
|
||||
TRACE("pb", display(tout << "resolve with inequality", pbj->get_ineq(), true););
|
||||
process_ineq(pbj->get_ineq(), conseq, conseq_coeff);
|
||||
if (pbj == 0) {
|
||||
TRACE("pb", tout << "skip justification for " << conseq << "\n";);
|
||||
}
|
||||
else {
|
||||
TRACE("pb", tout << "skipping justification for " << conseq
|
||||
<< " from theory " << j->get_from_theory() << " "
|
||||
<< typeid(*j).name() << "\n";);
|
||||
m_ineq_literals.push_back(conseq);
|
||||
process_card(pbj->get_card(), offset);
|
||||
}
|
||||
break;
|
||||
}
|
||||
default:
|
||||
UNREACHABLE();
|
||||
}
|
||||
}
|
||||
|
||||
TRACE("pb",
|
||||
for (unsigned i = 0; i < m_ineq_literals.size(); ++i) {
|
||||
tout << m_ineq_literals[i] << " ";
|
||||
}
|
||||
display(tout << "=> ", m_lemma););
|
||||
process_next_resolvent:
|
||||
|
||||
// 3x + 3y + z + u >= 4
|
||||
// ~x /\ ~y => z + u >=
|
||||
|
||||
IF_VERBOSE(14, display(verbose_stream() << "lemma1: ", m_lemma););
|
||||
hoist_maximal_values();
|
||||
lbool is_true = m_lemma.normalize(false);
|
||||
m_lemma.prune(false);
|
||||
|
||||
IF_VERBOSE(14, display(verbose_stream() << "lemma2: ", m_lemma););
|
||||
//unsigned l_size = m_ineq_literals.size() + ((is_true==l_false)?0:m_lemma.size());
|
||||
//if (s_min_l_size >= l_size) {
|
||||
// verbose_stream() << "(pb.conflict min size: " << l_size << ")\n";
|
||||
// s_min_l_size = l_size;
|
||||
//}
|
||||
//IF_VERBOSE(1, verbose_stream() << "(pb.conflict " << m_ineq_literals.size() << " " << m_lemma.size() << "\n";);
|
||||
switch(is_true) {
|
||||
case l_true:
|
||||
UNREACHABLE();
|
||||
return false;
|
||||
case l_false:
|
||||
inc_propagations(c);
|
||||
m_stats.m_num_conflicts++;
|
||||
for (unsigned i = 0; i < m_ineq_literals.size(); ++i) {
|
||||
m_ineq_literals[i].neg();
|
||||
// find the next marked variable in the assignment stack
|
||||
//
|
||||
while (true) {
|
||||
conseq = lits[idx];
|
||||
v = conseq.var();
|
||||
if (ctx.is_marked(v)) break;
|
||||
SASSERT(idx > 0);
|
||||
--idx;
|
||||
}
|
||||
TRACE("pb", tout << m_ineq_literals << "\n";);
|
||||
ctx.mk_clause(m_ineq_literals.size(), m_ineq_literals.c_ptr(), justify(m_ineq_literals), CLS_AUX_LEMMA, 0);
|
||||
break;
|
||||
default: {
|
||||
app_ref tmp = m_lemma.to_expr(false, ctx, get_manager());
|
||||
internalize_atom(tmp, false);
|
||||
ctx.mark_as_relevant(tmp.get());
|
||||
literal l(ctx.get_bool_var(tmp));
|
||||
add_assign(c, m_ineq_literals, l);
|
||||
break;
|
||||
}
|
||||
|
||||
SASSERT(ctx.get_assign_level(v) == m_conflict_lvl);
|
||||
ctx.unset_mark(v);
|
||||
--idx;
|
||||
--m_num_marks;
|
||||
}
|
||||
|
||||
TRACE("pb", display_resolved_lemma(tout << "done\n"););
|
||||
|
||||
return true;
|
||||
}
|
||||
|
||||
|
|
@ -2219,30 +2098,6 @@ namespace smt {
|
|||
return js;
|
||||
}
|
||||
|
||||
void theory_pb::hoist_maximal_values() {
|
||||
for (unsigned i = 0; i < m_lemma.size(); ++i) {
|
||||
if (m_lemma.coeff(i) >= m_lemma.k()) {
|
||||
m_ineq_literals.push_back(~m_lemma.lit(i));
|
||||
std::swap(m_lemma[i], m_lemma[m_lemma.size()-1]);
|
||||
m_lemma.pop_back();
|
||||
--i;
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
void theory_pb::remove_from_lemma(unsigned idx) {
|
||||
// Remove conseq from lemma:
|
||||
literal lit = m_lemma.lit(idx);
|
||||
unsigned last = m_lemma.size()-1;
|
||||
if (idx != last) {
|
||||
m_lemma[idx] = m_lemma[last];
|
||||
m_conseq_index[m_lemma.lit(idx).var()] = idx;
|
||||
}
|
||||
m_lemma.pop_back();
|
||||
unset_mark(lit.var());
|
||||
--m_num_marks;
|
||||
}
|
||||
|
||||
// debug methods
|
||||
|
||||
void theory_pb::validate_watch(ineq const& c) const {
|
||||
|
|
@ -2333,32 +2188,45 @@ namespace smt {
|
|||
unsigned lvl;
|
||||
out << "num marks: " << m_num_marks << "\n";
|
||||
out << "conflict level: " << m_conflict_lvl << "\n";
|
||||
for (unsigned i = 0; i < lits.size(); ++i) {
|
||||
for (unsigned i = lits.size(); i > 0;) {
|
||||
--i;
|
||||
v = lits[i].var();
|
||||
lvl = ctx.get_assign_level(v);
|
||||
out << lits[i]
|
||||
<< "@ " << lvl
|
||||
<< " " << (is_marked(v)?"m":"u")
|
||||
<< "\n";
|
||||
|
||||
if (lvl == m_conflict_lvl && is_marked(v)) {
|
||||
out << "skipped: " << lits[i] << ":"<< i << "\n";
|
||||
out << lvl << ": " << lits[i] << " " << (ctx.is_marked(v)?"m":"u") << " ";
|
||||
ctx.display(out, ctx.get_justification(v));
|
||||
}
|
||||
|
||||
if (!m_antecedents.empty()) {
|
||||
out << m_antecedents << " ==> ";
|
||||
}
|
||||
int bound = m_bound;
|
||||
uint_set seen;
|
||||
for (unsigned i = 0; i < m_active_coeffs.size(); ++i) {
|
||||
bool_var v = m_active_coeffs[i];
|
||||
if (seen.contains(v)) {
|
||||
continue;
|
||||
}
|
||||
seen.insert(v);
|
||||
int coeff = get_coeff(v);
|
||||
if (coeff == 0) {
|
||||
// skip
|
||||
}
|
||||
else if (coeff == 1) {
|
||||
out << literal(v) << " ";
|
||||
}
|
||||
else if (coeff == -1) {
|
||||
out << literal(v, true) << " ";
|
||||
bound -= coeff;
|
||||
}
|
||||
else if (coeff > 0) {
|
||||
out << coeff << " " << literal(v) << " ";
|
||||
}
|
||||
else {
|
||||
out << (-coeff) << " " << literal(v, true) << " ";
|
||||
bound -= coeff;
|
||||
}
|
||||
}
|
||||
display(out, m_lemma, true);
|
||||
|
||||
unsigned nc = 0;
|
||||
for (unsigned i = 0; i < m_lemma.size(); ++i) {
|
||||
v = m_lemma.lit(i).var();
|
||||
lvl = ctx.get_assign_level(v);
|
||||
if (lvl == m_conflict_lvl) ++nc;
|
||||
out << m_lemma.lit(i)
|
||||
<< "@" << lvl
|
||||
<< " " << (is_marked(v)?"m":"u")
|
||||
<< " " << ctx.get_assignment(m_lemma.lit(i))
|
||||
<< "\n";
|
||||
}
|
||||
out << "num conflicts: " << nc << "\n";
|
||||
out << " >= " << bound << "\n";
|
||||
}
|
||||
|
||||
std::ostream& theory_pb::display(std::ostream& out, arg_t const& c, bool values) const {
|
||||
|
|
|
|||
|
|
@ -225,7 +225,7 @@ namespace smt {
|
|||
|
||||
bool validate_assign(theory_pb& th, literal_vector const& lits, literal l);
|
||||
|
||||
void set_conflict(theory_pb& th, literal l1, literal l2);
|
||||
void set_conflict(theory_pb& th, literal l);
|
||||
};
|
||||
|
||||
typedef ptr_vector<card> card_watch;
|
||||
|
|
@ -366,22 +366,19 @@ namespace smt {
|
|||
//
|
||||
unsigned m_num_marks;
|
||||
unsigned m_conflict_lvl;
|
||||
arg_t m_lemma;
|
||||
literal_vector m_ineq_literals;
|
||||
svector<bool_var> m_marked;
|
||||
svector<int> m_coeffs;
|
||||
svector<bool_var> m_active_coeffs;
|
||||
int m_bound;
|
||||
literal_vector m_antecedents;
|
||||
|
||||
// bool_var |-> index into m_lemma
|
||||
unsigned_vector m_conseq_index;
|
||||
static const unsigned null_index;
|
||||
bool is_marked(bool_var v) const;
|
||||
void set_mark(bool_var v, unsigned idx);
|
||||
void unset_mark(bool_var v);
|
||||
void unset_marks();
|
||||
void inc_coeff(literal l, int offset);
|
||||
int get_coeff(bool_var v) const;
|
||||
|
||||
bool resolve_conflict(ineq& c);
|
||||
void process_antecedent(literal l, numeral coeff);
|
||||
void process_ineq(ineq& c, literal conseq, numeral coeff);
|
||||
void remove_from_lemma(unsigned idx);
|
||||
void reset_coeffs();
|
||||
|
||||
bool resolve_conflict(card& c, literal_vector const& conflict_clause);
|
||||
void process_antecedent(literal l, int offset);
|
||||
void process_card(card& c, int offset);
|
||||
bool is_proof_justification(justification const& j) const;
|
||||
|
||||
void hoist_maximal_values();
|
||||
|
|
|
|||
Loading…
Add table
Add a link
Reference in a new issue