more accurate init of the relation between polynomial properties

Signed-off-by: Lev Nachmanson <levnach@hotmail.com>

src/nlsat/levelwise.cpp

@@ -3,6 +3,7 @@
 #include <vector>
 #include <unordered_map>
 #include <map>
+#include <algorithm>
 namespace nlsat {
 
 // Local enums reused from previous scaffolding
@@ -12,6 +13,8 @@ namespace nlsat {
         ir_ord,
         an_del,
         non_null,
+        ord_inv_reducible,
+        ord_inv_irreducible,
         sgn_inv_reducible,
         sgn_inv_irreducible,
         connected,
@@ -22,9 +25,8 @@ namespace nlsat {
         _count 
     };
 
-    static unsigned score(prop_enum pe) {
+    unsigned prop_count() { return static_cast<unsigned>(prop_enum::_count);}
-        return static_cast<unsigned>(prop_enum::_count) - static_cast<unsigned>(pe);
+    // no score-based ordering; precedence is defined by m_p_relation only
-    }
     
     struct property {
         prop_enum prop;
@@ -39,9 +41,73 @@ namespace nlsat {
         std::vector<property>        m_Q; // the set of properties to prove as in single_cell
         bool                         m_fail = false;
         unsigned                     m_i; // current level
+        // Property precedence relation stored as pairs (lesser, greater)
+        std::vector<std::pair<prop_enum, prop_enum>> m_p_relation;
+        // Transitive closure matrix: dom[a][b] == true iff a ▹ b (a strictly dominates b).
+        // Since m_p_relation holds (lesser -> greater), we invert edges when populating dom: greater ▹ lesser.
+        std::vector<std::vector<bool>> m_prop_dom;
         // max_x plays the role of n in algorith 1 of the levelwise paper.
         impl(polynomial_ref_vector const& ps, var max_x, assignment const& s)
             : m_P(ps), m_n(max_x), m_s(s) {
+            init_relation();
+        }
+
+        #ifdef Z3DEBUG
+        
+        bool check_prop_init() {
+            std::cout << "checked\n";
+            for (unsigned k = 0; k < prop_count(); ++k)
+                if (m_prop_dom[k][k])
+                    return false;
+            return !dominates(prop_enum::ord_inv_irreducible, prop_enum::non_null);
+        }
+        #endif
+        
+        void init_relation() {
+            m_p_relation.clear();
+            auto add = [&](prop_enum lesser, prop_enum greater) { m_p_relation.emplace_back(lesser, greater); };
+            // m_p_relation stores edges (lesser -> greater). We later invert these to build dom (greater ▹ lesser).
+            // The edges below follow Figure 8. Examples include: an_del -> ir_ord, sample -> ir_ord.
+            add(prop_enum::holds,   prop_enum::repr);
+            add(prop_enum::repr,    prop_enum::sample);
+            add(prop_enum::sample,  prop_enum::an_sub);
+            add(prop_enum::an_sub,  prop_enum::connected);
+            // connected < sgn_inv_*
+            add(prop_enum::connected, prop_enum::sgn_inv_reducible);
+            add(prop_enum::connected, prop_enum::sgn_inv_irreducible);
+            // sgn_inv_* < ord_inv_* (same reducibility)
+            add(prop_enum::sgn_inv_reducible,   prop_enum::ord_inv_reducible);
+            add(prop_enum::sgn_inv_irreducible, prop_enum::ord_inv_irreducible);
+            // ord_inv_* < non_null
+
+            add(prop_enum::ord_inv_reducible,   prop_enum::non_null);
+            add(prop_enum::ord_inv_irreducible, prop_enum::non_null);
+            // non_null < an_del
+            add(prop_enum::non_null, prop_enum::an_del);
+            // an_del < ir_ord
+            add(prop_enum::an_del,    prop_enum::ir_ord);
+            // Additional explicit edge from Fig 8
+            add(prop_enum::sample,    prop_enum::ir_ord);
+
+            // Build transitive closure matrix for quick comparisons
+            unsigned N = prop_count();
+            m_prop_dom.assign(N, std::vector<bool>(N, false));
+            for (auto const& pr : m_p_relation) {
+                unsigned lesser  = static_cast<unsigned>(pr.first);
+                unsigned greater = static_cast<unsigned>(pr.second);
+                // Build dominance relation as: greater ▹ lesser
+                m_prop_dom[greater][lesser] = true;
+            }
+            // Floyd-Warshall style closure on a tiny fixed-size set
+            for (unsigned k = 0; k < N; ++k)
+                for (unsigned i = 0; i < N; ++i)
+                    if (m_prop_dom[i][k])
+                        for (unsigned j = 0; j < N; ++j)
+                            if (m_prop_dom[k][j])
+                                m_prop_dom[i][j] = true;
+
+
+            SASSERT(check_prop_init());            
         }
         std::vector<property> seed_properties() {
             std::vector<property> Q;
@@ -58,25 +124,48 @@ namespace nlsat {
             bool status;
         };
         
+        bool dominates(prop_enum a, prop_enum b) {
+            return m_prop_dom[static_cast<unsigned>(a)][static_cast<unsigned>(b)];
+        }
 
         
         std::vector<property> greatest_to_refine() {
-            // Deterministic order: use ascending polynomial id as key
+            // Collect candidates on current level, excluding sgn_inv_irreducible
-            std::map<unsigned, property> best_by_poly;
+            std::vector<property> cand;
-            for (const auto& q : m_Q) {
+            cand.reserve(m_Q.size());
-                if (q.level != m_i)
+            for (const auto& q : m_Q)
-                    continue;
+                if (q.level == m_i && q.prop != prop_enum::sgn_inv_irreducible)
-                if (q.prop == prop_enum::sgn_inv_irreducible)
+                    cand.push_back(q);
-                    continue;
+            if (cand.empty()) return {};
-                unsigned pid = polynomial::manager::id(q.p);
+
-                auto it = best_by_poly.find(pid);
+            // Determine maxima w.r.t. ▹ using the transitive closure matrix
-                if (it == best_by_poly.end() || score(q.prop) > score(it->second.prop))
+
-                    best_by_poly[pid] = q;
+            std::vector<bool> dominated(cand.size(), false);
+            for (size_t i = 0; i < cand.size(); ++i) {
+                for (size_t j = 0; j < cand.size(); ++j) {
+                    if (i != j && dominates(cand[j].prop, cand[i].prop)) {
+                        dominated[i] = true;
+                        break;
                     }
+                }
+            }
+
+            // Extract non-dominated (greatest) candidates; keep deterministic order by (poly id, prop enum)
+            struct Key { unsigned pid; unsigned pprop; size_t idx; };
+            std::vector<Key> keys;
+            keys.reserve(cand.size());
+            for (size_t i = 0; i < cand.size(); ++i) {
+                if (!dominated[i]) {
+                    keys.push_back(Key{ polynomial::manager::id(cand[i].p), static_cast<unsigned>(cand[i].prop), i });
+                }
+            }
+            std::sort(keys.begin(), keys.end(), [](Key const& a, Key const& b){
+                if (a.pid != b.pid) return a.pid < b.pid;
+                return a.pprop < b.pprop;
+            });
             std::vector<property> ret;
-            ret.reserve(best_by_poly.size());
+            ret.reserve(keys.size());
-            for (auto const& kv : best_by_poly)
+            for (auto const& k : keys) ret.push_back(cand[k.idx]);
-                ret.push_back(kv.second);
             return ret;
         }
 
@@ -89,10 +178,7 @@ do
   4 return FAIL
 */        
             std::vector<property> to_refine = greatest_to_refine();
-           for (const auto & q : this->m_Q) {
+            // refine using to_refine (TBD)
-               if (false)
-                   ;
-           }
             return ret;
         }
         // return an empty vector on failure