Enable model construction and evaluation for theory functions that may be uninterpreted. To fix issue #237

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

src/smt/smt_model_generator.cpp

@@ -400,7 +400,12 @@ namespace smt {
        \brief Return true if the interpretation of the function should be included in the model.
     */
     bool model_generator::include_func_interp(func_decl * f) const {
-        return f->get_family_id() == null_family_id;
+        family_id fid = f->get_family_id();
+        if (fid == null_family_id) return true;
+        if (fid == m_manager.get_basic_family_id()) return false;
+        theory * th   = m_context->get_theory(fid);
+        if (!th) return true;
+        return th->include_func_interp(f);
     }
     
     /**

src/smt/smt_theory.h

@@ -412,6 +412,10 @@ namespace smt {
             return 0;
         }
 
+        virtual bool include_func_interp(func_decl* f) {
+            return false;
+        }
+
         // -----------------------------------
         //
         // Model checker

src/smt/theory_bv.cpp

@@ -1283,6 +1283,21 @@ namespace smt {
         theory::reset_eh();
     }
 
+    bool theory_bv::include_func_interp(func_decl* f) {
+        SASSERT(f->get_family_id() == get_family_id());
+        switch (f->get_decl_kind()) {
+        case OP_BSDIV0:
+        case OP_BUDIV0:
+        case OP_BSREM0:
+        case OP_BUREM0:       
+        case OP_BSMOD0:        
+            return true;
+        default:
+            return false;
+        }
+        return false;
+    }
+
     theory_bv::theory_bv(ast_manager & m, theory_bv_params const & params, bit_blaster_params const & bb_params):
         theory(m.mk_family_id("bv")),
         m_params(params),

src/smt/theory_bv.h

@@ -236,6 +236,7 @@ namespace smt {
         virtual void pop_scope_eh(unsigned num_scopes);
         virtual final_check_status final_check_eh();
         virtual void reset_eh();
+        virtual bool include_func_interp(func_decl* f);
         svector<theory_var>   m_merge_aux[2]; //!< auxiliary vector used in merge_zero_one_bits
         bool merge_zero_one_bits(theory_var r1, theory_var r2);