factor out relation context for datalog

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

src/muz_qe/rel_context.h

@@ -0,0 +1,115 @@
+/*++
+Copyright (c) 2012 Microsoft Corporation
+
+Module Name:
+
+    rel_context.h
+
+Abstract:
+
+    context for relational datalog engine.
+
+Author:
+
+    Nikolaj Bjorner (nbjorner) 2012-12-3.
+
+Revision History:
+
+    Extracted from dl_context
+
+--*/
+#ifndef _REL_CONTEXT_H_
+#define _REL_CONTEXT_H_
+#include "ast.h"
+#include "dl_relation_manager.h"
+#include "lbool.h"
+
+namespace datalog {
+
+    class context;
+
+    class rel_context {
+        typedef vector<std::pair<func_decl*,relation_fact> > fact_vector;
+
+        context&           m_context;
+        ast_manager&       m;
+        relation_manager   m_rmanager;
+        expr_ref           m_answer;
+        volatile bool      m_cancel;
+        relation_base *    m_last_result_relation;
+        decl_set           m_output_preds;
+        fact_vector        m_table_facts;
+
+        void reset_negated_tables();
+
+        lbool saturate();
+        
+        relation_plugin & get_ordinary_relation_plugin(symbol relation_name);
+        
+        void reset_tables();
+
+    public:
+        rel_context(context& ctx);
+
+        ~rel_context();
+
+        relation_manager & get_rmanager();
+        const relation_manager & get_rmanager() const;
+        ast_manager& get_manager() { return m; }
+        context&     get_context() { return m_context; }
+        relation_base & get_relation(func_decl * pred); 
+        relation_base * try_get_relation(func_decl * pred) const; 
+        expr_ref get_last_answer() { return m_answer; }
+
+        bool output_profile() const;
+
+
+        lbool query(expr* q);
+        lbool query(unsigned num_rels, func_decl * const* rels);
+
+        void set_predicate_representation(func_decl * pred, unsigned relation_name_cnt, 
+                                          symbol const * relation_names);
+        
+        void inherit_predicate_kind(func_decl* new_pred, func_decl* orig_pred);
+
+        void cancel() { m_cancel = true; }
+
+
+
+        /**
+           \brief Restrict the set of used predicates to \c res.
+
+           The function deallocates unsused relations, it does not deal with rules.
+         */
+        void restrict_predicates(const decl_set & res);
+
+        void collect_predicates(decl_set & res);        
+
+        void set_output_predicate(func_decl * pred);
+        bool is_output_predicate(func_decl * pred) { return m_output_preds.contains(pred); }
+        const decl_set & get_output_predicates() const { return m_output_preds; }
+
+
+        /**
+           \brief query result if it contains fact.
+         */
+        bool result_contains_fact(relation_fact const& f);
+
+        void add_fact(func_decl* pred, relation_fact const& fact);
+
+        void add_fact(func_decl* pred, table_fact const& fact);
+        
+        /**
+           \brief Store the relation \c rel under the predicate \c pred. The \c context object
+           takes over the ownership of the relation object.
+        */
+        void store_relation(func_decl * pred, relation_base * rel);
+
+        void display_output_facts(std::ostream & out) const;
+        void display_facts(std::ostream & out) const;
+
+
+    };
+};
+
+#endif /* _REL_CONTEXT_H_ */