fix hidden tautology bug on non-learned clauses

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

src/sat/sat_asymm_branch.cpp

@@ -399,13 +399,11 @@ namespace sat {
     bool asymm_branch::process_sampled(big& big, clause & c) {
         scoped_detach scoped_d(s, c);
         sort(big, c);
-#if 1
-        if (uhte(big, c)) {
+        if (c.is_learned() && uhte(big, c)) {
             ++m_hidden_tautologies;
             scoped_d.del_clause();
             return false;
         }
-#endif
         return uhle(scoped_d, big, c);        
     }
 

src/sat/sat_elim_vars.cpp

@@ -88,6 +88,7 @@ namespace sat{
         simp.collect_clauses(pos_l, simp.m_pos_cls);
         simp.collect_clauses(neg_l, simp.m_neg_cls);
         VERIFY(!simp.is_external(v));
+
         model_converter::entry & mc_entry = s.m_mc.mk(model_converter::ELIM_VAR, v);
         simp.save_clauses(mc_entry, simp.m_pos_cls);
         simp.save_clauses(mc_entry, simp.m_neg_cls);
@@ -100,7 +101,7 @@ namespace sat{
         pos_occs.reset();
         neg_occs.reset();
         literal_vector lits;
-        add_clauses(b, lits); 
+        add_clauses(b, lits);         
         return true;
     }
 

src/sat/sat_model_converter.cpp

@@ -275,14 +275,7 @@ namespace sat {
     }
 
     std::ostream& model_converter::display(std::ostream& out, entry const& entry) const {
-        out << "  (";
-        switch (entry.get_kind()) {
-        case ELIM_VAR: out << "elim"; break;
-        case BLOCK_LIT: out << "blocked"; break;
-        case CCE: out << "cce"; break;
-        case ACCE: out << "acce"; break;
-        }
-        out << " " << entry.var();
+        out << "  (" << entry.get_kind() << " " << entry.var(); 
         bool start = true;
         unsigned index = 0;
         for (literal l : entry.m_clauses) {

src/sat/sat_model_converter.h

@@ -134,6 +134,16 @@ namespace sat {
         void expand(literal_vector& update_stack);
     };
 
+    inline std::ostream& operator<<(std::ostream& out, model_converter::kind k) {
+        switch (k) {
+        case model_converter::ELIM_VAR: out << "elim"; break;
+        case model_converter::BLOCK_LIT: out << "blocked"; break;
+        case model_converter::CCE: out << "cce"; break;
+        case model_converter::ACCE: out << "acce"; break;
+        }
+        return out;
+    }
+
 };
 
 #endif

src/sat/sat_simplifier.cpp

@@ -1818,6 +1818,7 @@ namespace sat {
 
                     if (s.m_config.m_drat) s.m_drat.add(*new_c, true);
                     s.m_clauses.push_back(new_c);
+
                     m_use_list.insert(*new_c);
                     if (m_sub_counter > 0)
                         back_subsumption1(*new_c);
@@ -1829,6 +1830,7 @@ namespace sat {
                     return true;
             }
         }
+
         return true;
     }
 

src/sat/sat_solver.cpp

@@ -3225,7 +3225,9 @@ namespace sat {
                 literal l2 = w.get_literal();
                 if (l.index() > l2.index())
                     continue;
-                out << "(" << l << " " << l2 << ")\n";
+                out << "(" << l << " " << l2 << ")";
+                if (w.is_learned()) out << "*";
+                out << "\n";
             }
         }
     }

src/sat/tactic/goal2sat.cpp

@@ -142,6 +142,7 @@ struct goal2sat::imp {
                 sat::bool_var v = m_solver.mk_var(ext);
                 m_map.insert(t, v);
                 l = sat::literal(v, sign);
+                // if (to_app(t)->get_decl()->get_name() == "XX") IF_VERBOSE(0, verbose_stream() << mk_ismt2_pp(t, m) << ": " << "v" << v << "\n";);
                 TRACE("sat", tout << "new_var: " << v << ": " << mk_ismt2_pp(t, m) << "\n";);
                 if (ext && !is_uninterp_const(t)) {
                     m_interpreted_atoms.push_back(t);
@@ -1025,6 +1026,7 @@ void sat2goal::mc::insert(sat::bool_var v, app * atom, bool aux) {
 expr_ref sat2goal::mc::lit2expr(sat::literal l) {
     if (!m_var2expr.get(l.var())) {
         app* aux = m.mk_fresh_const(0, m.mk_bool_sort());
+        // if (aux->get_decl()->get_name() == "k!81740") IF_VERBOSE(0, verbose_stream() << mk_ismt2_pp(aux, m) << ": " << "v" << l.var() << "\n";);
         m_var2expr.set(l.var(), aux);
     }
     VERIFY(m_var2expr.get(l.var()));
@@ -1067,6 +1069,7 @@ struct sat2goal::imp {
             app* aux = mc ? mc->var2expr(l.var()) : nullptr;
             if (!aux) {
                 aux = m.mk_fresh_const(0, m.mk_bool_sort());
+                // if (aux->get_decl()->get_name() == "k!81740") IF_VERBOSE(0, verbose_stream() << mk_ismt2_pp(aux, m) << ": " << "v" << l.var() << "\n";);
                 if (mc)
                     mc->insert(l.var(), aux, true);
             }