fixing model construction for underspecified operators

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

src/ast/sls/sls_arith_base.cpp

@@ -2310,9 +2310,6 @@ namespace sls {
         SASSERT(val == i.m_args_value);
     }
 
-    template<typename num_t>
-    void arith_base<num_t>::mk_model(model& mdl) {
-    }
 
     template<typename num_t>
     void arith_base<num_t>::collect_statistics(statistics& st) const {

src/ast/sls/sls_arith_base.h

@@ -277,7 +277,6 @@ namespace sls {
         void on_rescale() override;
         void on_restart() override;
         std::ostream& display(std::ostream& out) const override;
-        void mk_model(model& mdl) override;
         void collect_statistics(statistics& st) const override;
         void reset_statistics() override;
     };

src/ast/sls/sls_arith_plugin.cpp

@@ -99,10 +99,6 @@ namespace sls {
             return m_arith->display(out);                
     }
 
-    void arith_plugin::mk_model(model& mdl) {
-        WITH_FALLBACK(mk_model(mdl));        
-    }
-
     bool arith_plugin::repair_down(app* e) {
         WITH_FALLBACK(repair_down(e));
     }

src/ast/sls/sls_arith_plugin.h

@@ -43,7 +43,6 @@ namespace sls {
         void on_rescale() override;
         void on_restart() override;
         std::ostream& display(std::ostream& out) const override;
-        void mk_model(model& mdl) override;
         bool set_value(expr* e, expr* v) override;
 
         void collect_statistics(statistics& st) const override;

src/ast/sls/sls_array_plugin.h

@@ -82,7 +82,6 @@ namespace sls {
         void on_rescale() override {}
         void on_restart() override {}
         std::ostream& display(std::ostream& out) const override;
-        void mk_model(model& mdl) override {}
         bool set_value(expr* e, expr* v) override { return false; }
         void collect_statistics(statistics& st) const override {}
         void reset_statistics() override {}

src/ast/sls/sls_basic_plugin.h

@@ -51,7 +51,6 @@ namespace sls {
         void on_rescale() override {}
         void on_restart() override {}
         std::ostream& display(std::ostream& out) const override;
-        void mk_model(model& mdl) override {}
         bool set_value(expr* e, expr* v) override;
         void collect_statistics(statistics& st) const override {}
         void reset_statistics() override {}

src/ast/sls/sls_bv_plugin.h

@@ -54,7 +54,6 @@ namespace sls {
         void on_rescale() override {}
         void on_restart() override {}
         std::ostream& display(std::ostream& out) const override;
-        void mk_model(model& mdl) override {}
         bool set_value(expr* e, expr* v) override;
         void collect_statistics(statistics& st) const override {}
         void reset_statistics() override {}

src/ast/sls/sls_context.cpp

@@ -129,22 +129,47 @@ namespace sls {
                 return l_undef;
 
             if (all_of(m_plugins, [&](auto* p) { return !p || p->is_sat(); })) {
-                model_ref mdl = alloc(model, m);
+                values2model();
-                for (expr* e : subterms()) 
-                    if (is_uninterp_const(e))
-                        mdl->register_decl(to_app(e)->get_decl(), get_value(e));                
-                for (auto p : m_plugins)
-                    if (p)
-                        p->mk_model(*mdl);
-                s.on_model(mdl);
-                // verbose_stream() << *mdl << "\n";
-                TRACE("sls", display(tout));
                 return l_true;
             }
         }
         return l_undef;
     }
 
+    void context::values2model() {
+        model_ref mdl = alloc(model, m);
+        expr_ref_vector args(m);
+        for (expr* e : subterms()) 
+            if (is_uninterp_const(e))
+                mdl->register_decl(to_app(e)->get_decl(), get_value(e));
+        
+        for (expr* e : subterms()) {
+            if (!is_app(e))
+                continue;
+            auto f = to_app(e)->get_decl();
+            if (!include_func_interp(f))
+                continue;
+            auto v = get_value(e);
+            auto fi = mdl->get_func_interp(f);
+            if (!fi) {
+                fi = alloc(func_interp, m, f->get_arity());
+                mdl->register_decl(f, fi);
+            }
+            args.reset();                
+            for (expr* arg : *to_app(e)) {
+                args.push_back(get_value(arg));
+                SASSERT(args.back());
+            }
+            SASSERT(f->get_arity() == args.size());
+            if (!fi->get_entry(args.data()))
+                fi->insert_new_entry(args.data(), v);
+        }
+                
+        s.on_model(mdl);
+        // verbose_stream() << *mdl << "\n";
+        TRACE("sls", display(tout));
+    }
+    
     void context::propagate_boolean_assignment() {
         reinit_relevant();
 
@@ -158,7 +183,6 @@ namespace sls {
         if (m_new_constraint)
             return;        
 
-
         while (!m_new_constraint && m.inc() && (!m_repair_up.empty() || !m_repair_down.empty())) {
             while (!m_repair_down.empty() && !m_new_constraint && m.inc()) {
                 auto id = m_repair_down.erase_min();
@@ -264,10 +288,7 @@ namespace sls {
     }
 
     bool context::set_value(expr * e, expr * v) {
-        for (auto p : m_plugins)
+        return any_of(m_plugins, [&](auto p) { return p && p->set_value(e, v); });
-            if (p && p->set_value(e, v))
-                return true;
-        return false;
     }
     
     bool context::is_relevant(expr* e) {

src/ast/sls/sls_context.h

@@ -53,10 +53,10 @@ namespace sls {
         virtual void on_rescale() {};
         virtual void on_restart() {};
         virtual std::ostream& display(std::ostream& out) const = 0;
-        virtual void mk_model(model& mdl) = 0;
         virtual bool set_value(expr* e, expr* v) = 0;
         virtual void collect_statistics(statistics& st) const = 0;
         virtual void reset_statistics() = 0;
+        virtual bool include_func_interp(func_decl* f) const { return false; }
     };
 
     using clause = ptr_iterator<sat::literal>;
@@ -139,6 +139,8 @@ namespace sls {
         void propagate_literal(sat::literal lit);
         void repair_literals();
 
+        void values2model();
+
         void ensure_plugin(expr* e);
         void ensure_plugin(family_id fid);
         family_id get_fid(expr* e) const;
@@ -181,6 +183,7 @@ namespace sls {
         bool is_unit(sat::literal lit) const { return m_unit_indices.contains(lit.index()); }
         void reinit_relevant();
         void force_restart() { s.force_restart(); }
+        bool include_func_interp(func_decl* f) const { return any_of(m_plugins, [&](plugin* p) { return p && p->include_func_interp(f); }); }
 
         ptr_vector<expr> const& parents(expr* e) { 
             m_parents.reserve(e->get_id() + 1); 

src/ast/sls/sls_datatype_plugin.cpp

@@ -384,7 +384,7 @@ namespace sls {
         m_model = nullptr;
     }
 
-    euf::enode* datatype_plugin::get_constructor(euf::enode* n) {
+    euf::enode* datatype_plugin::get_constructor(euf::enode* n) const {
         euf::enode* con = nullptr;
         for (auto sib : euf::enode_class(n))
             if (dt.is_constructor(sib->get_expr()))
@@ -395,22 +395,22 @@ namespace sls {
     bool datatype_plugin::propagate() {       
         enum color_t { white, grey, black };
         svector<color_t> color;
-        svector<std::tuple<euf::enode*, unsigned>> todo;
+        ptr_vector<euf::enode> stack;
         obj_map<sort, ptr_vector<expr>> sorts;
 
-        auto set_conflict = [&](euf::enode* n, unsigned parent_idx) {
+        auto set_conflict = [&](euf::enode* n) {
             expr_ref_vector diseqs(m);
             while (true) {
-                auto [n2, parent_idx2] = todo[parent_idx];
+                auto n2 = stack.back();
                 auto con2 = get_constructor(n2);
                 if (n2 != con2)
                     diseqs.push_back(m.mk_not(m.mk_eq(n2->get_expr(), con2->get_expr())));
-                parent_idx = parent_idx2;
                 if (n2->get_root() == n->get_root()) {
                     if (n != n2)
                         diseqs.push_back(m.mk_not(m.mk_eq(n->get_expr(), n2->get_expr())));
                     break;
                 }
+                stack.pop_back();
             }
             IF_VERBOSE(1, verbose_stream() << "cycle\n"; for (auto e : diseqs) verbose_stream() << mk_pp(e, m) << "\n";);
             ctx.add_constraint(m.mk_or(diseqs));
@@ -437,49 +437,44 @@ namespace sls {
             // is a node in the same congruence class as n that is a constructor.
             // For every cycle accumulate a conflict.
 
-            todo.push_back({ n, 0});
+            stack.push_back(n);
-            while (!todo.empty()) {
+            while (!stack.empty()) {
-                auto [n, parent_idx] = todo.back();
+                n = stack.back();
                 unsigned id = n->get_root_id();
                 c = color.get(id, white);
                 euf::enode* con;
-                unsigned idx; 
 
                 switch (c) {
                 case black:
-                    todo.pop_back();
+                    stack.pop_back();
                     break;
                 case grey:
-                case white: {
+                case white: 
-                    bool new_child = false;
                     color.setx(id, grey, white);
                     con = get_constructor(n);
-                    idx = todo.size() - 1;
+                    if (!con)
-                    if (con) {
+                        goto done_with_node;
                     for (auto child : euf::enode_args(con)) {
                         auto c2 = color.get(child->get_root_id(), white);
                         switch (c2) {
                         case black:
                             break;
                         case grey:
-                                    set_conflict(child, idx);
+                            set_conflict(child);
                             return true;
                         case white:
-                                    todo.push_back({ child, idx });
+                            stack.push_back(child);
-                                    new_child = true;
+                            goto node_pushed;
-                                    break;
                         }
                     }
-                    }                    
+                done_with_node:
-                    if (!new_child) {
                     color[id] = black;
-                        todo.pop_back();
+                    stack.pop_back();
-                    }
+                node_pushed:
                     break;                
                 }
             }                    
         }
-        }
 
 
         for (auto const& [s, elems] : sorts) {
@@ -493,6 +488,18 @@ namespace sls {
         return false;
     }
 
+    bool datatype_plugin::include_func_interp(func_decl* f) const {
+        if (!dt.is_accessor(f))
+            return false;
+        func_decl* con_decl = dt.get_accessor_constructor(f);
+        for (euf::enode* app : g->enodes_of(f)) {   
+            euf::enode* con = get_constructor(app->get_arg(0));
+            if (con && con->get_decl() != con_decl) 
+                return true;
+        }
+        return false; 
+    }
+
     std::ostream& datatype_plugin::display(std::ostream& out) const {
         for (auto a : m_axioms)
             out << mk_bounded_pp(a, m, 3) << "\n";
@@ -504,10 +511,8 @@ namespace sls {
     }
    
     bool datatype_plugin::is_sat() { return true; }
-    void datatype_plugin::register_term(expr* e) {}
     
-    void datatype_plugin::mk_model(model& mdl) {
+    void datatype_plugin::register_term(expr* e) {}
-    }
         
     void datatype_plugin::collect_statistics(statistics& st) const {
         st.update("sls-dt-axioms", m_axioms.size());

src/ast/sls/sls_datatype_plugin.h

@@ -38,7 +38,7 @@ namespace sls {
         obj_map<sort, ptr_vector<expr>> m_dts;
         obj_map<expr, svector<parent_t>> m_parents;
         
-        datatype_util dt;
+        mutable datatype_util dt;
         expr_ref_vector m_axioms, m_values;
         model_ref m_model;
         stats m_stats;
@@ -52,7 +52,7 @@ namespace sls {
         void init_values();
         void add_dep(euf::enode* n, top_sort<euf::enode>& dep);
 
-        euf::enode* get_constructor(euf::enode* n);
+        euf::enode* get_constructor(euf::enode* n) const;
 
     public:
         datatype_plugin(context& c);
@@ -66,7 +66,6 @@ namespace sls {
         bool is_sat() override;
         void register_term(expr* e) override;
         std::ostream& display(std::ostream& out) const override;
-        void mk_model(model& mdl) override;
         bool set_value(expr* e, expr* v) override { return false; }
 
         void repair_up(app* e) override {}
@@ -75,6 +74,9 @@ namespace sls {
 
         void collect_statistics(statistics& st) const override;
         void reset_statistics() override;
+
+        bool include_func_interp(func_decl* f) const override;
+        
     };
     
 }

src/ast/sls/sls_euf_plugin.cpp

@@ -339,6 +339,9 @@ namespace sls {
         return expr_ref(e, m);
     }
 
+    bool euf_plugin::include_func_interp(func_decl* f) const {
+        return is_uninterp(f) && f->get_arity() > 0;
+    }
 
     bool euf_plugin::is_sat() {
         for (auto& [f, ts] : m_app) {
@@ -477,25 +480,6 @@ namespace sls {
         return out;
     }
 
-    void euf_plugin::mk_model(model& mdl) {
-        expr_ref_vector args(m);
-        for (auto& [f, ts] : m_app) {
-            func_interp* fi = alloc(func_interp, m, f->get_arity());
-            mdl.register_decl(f, fi);
-            m_values.reset();
-            for (auto* t : ts) {
-                if (m_values.contains(t))
-                    continue;
-                args.reset();
-                expr_ref val = ctx.get_value(t);
-                for (auto arg : *t) 
-                    args.push_back(ctx.get_value(arg));
-                fi->insert_new_entry(args.data(), val);
-                m_values.insert(t);
-            }
-        }
-    }
-
     void euf_plugin::collect_statistics(statistics& st) const {
         st.update("sls-euf-conflict", m_stats.m_num_conflicts);
     }

src/ast/sls/sls_euf_plugin.h

@@ -79,8 +79,8 @@ namespace sls {
         bool is_sat() override;
         void register_term(expr* e) override;
         std::ostream& display(std::ostream& out) const override;
-        void mk_model(model& mdl) override;
         bool set_value(expr* e, expr* v) override { return false; }
+        bool include_func_interp(func_decl* f) const override;
 
         void repair_up(app* e) override {}
         bool repair_down(app* e) override { return false; }
@@ -89,6 +89,8 @@ namespace sls {
         void collect_statistics(statistics& st) const override;
         void reset_statistics() override;
 
+
+
         scoped_ptr<euf::egraph>& egraph() { return m_g; }
     };