Z3 sources

Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>

lib/dl_mk_subsumption_checker.h

@@ -0,0 +1,93 @@
+/*++
+Copyright (c) 2006 Microsoft Corporation
+
+Module Name:
+
+    mk_subsumption_checker.h
+
+Abstract:
+
+    Rule transformer which checks for subsumption
+    (currently just for subsumption with total relations)
+
+Author:
+
+    Krystof Hoder (t-khoder) 2011-10-01.
+
+Revision History:
+
+--*/
+
+#ifndef _DL_MK_SUBSUMPTION_CHECKER_H_
+#define _DL_MK_SUBSUMPTION_CHECKER_H_
+
+#include "dl_context.h"
+#include "dl_rule_transformer.h"
+#include "dl_rule_subsumption_index.h"
+
+namespace datalog {
+
+    class mk_subsumption_checker : public rule_transformer::plugin {
+
+
+        ast_manager & m;
+        context & m_context;
+
+        rule_ref_vector m_ref_holder;
+
+        func_decl_set m_total_relations;
+
+        /** Map that for each relation contains the rule which implies its totality.
+        If the totality is due to the relation containing all facts, the rule stored 
+        here is zero*/
+        obj_map<func_decl, rule *> m_total_relation_defining_rules;
+
+
+        /**
+        Contains heads of rules of shape
+        R(c1,c2,...cN).
+        grouped by their predicate.
+
+        This information helps to improve the results of the 
+        scan_for_relations_total_due_to_facts() function.
+        */
+        obj_map<func_decl, obj_hashtable<app> *> m_ground_unconditional_rule_heads;
+
+
+        bool m_have_new_total_rule;
+        bool m_new_total_relation_discovery_during_transformation;
+
+        bool is_total_rule(const rule * r);
+
+
+
+        /** Function to be called when a new total relation is discovered */
+        void on_discovered_total_relation(func_decl * pred, rule * r);
+
+        void scan_for_total_rules(const rule_set & rules);
+        void scan_for_relations_total_due_to_facts();
+
+        void collect_ground_unconditional_rule_heads(const rule_set & rules);
+
+        /** Return false if rule is unsatisfiable */
+        bool transform_rule(rule * r, rule_subsumption_index& subs_index, rule_ref & res);
+        /** Return false if the rule set hasn't changed */
+        bool transform_rules(const rule_set & orig, rule_set & tgt);
+    public:
+        mk_subsumption_checker(context & ctx, unsigned priority=31000)
+            : plugin(priority),
+            m(ctx.get_manager()),
+            m_context(ctx),
+            m_ref_holder(ctx.get_rule_manager()),
+            m_new_total_relation_discovery_during_transformation(true) {}
+        ~mk_subsumption_checker() {
+            reset_dealloc_values(m_ground_unconditional_rule_heads);
+        }
+
+        rule_set * operator()(rule_set const & source, model_converter_ref& mc, proof_converter_ref& pc);
+    };
+
+};
+
+#endif /* _DL_MK_SUBSUMPTION_CHECKER_H_ */
+