Z3 sources

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

lib/smt_quantifier_stat.h

@@ -0,0 +1,140 @@
+/*++
+Copyright (c) 2006 Microsoft Corporation
+
+Module Name:
+
+    smt_quantifier_stat.h
+
+Abstract:
+
+    <abstract>
+
+Author:
+
+    Leonardo de Moura (leonardo) 2008-02-20.
+
+Revision History:
+
+--*/
+#ifndef _SMT_QUANTIFIER_STAT_H_
+#define _SMT_QUANTIFIER_STAT_H_
+
+#include"ast.h"
+#include"obj_hashtable.h"
+#include"approx_nat.h"
+#include"region.h"
+
+namespace smt {
+    
+    /**
+       \brief Store statistics for quantifiers. This information is
+       used to implement heuristics for quantifier instantiation.
+    */
+    class quantifier_stat {
+        unsigned m_size;
+        unsigned m_depth;
+        unsigned m_generation;
+        unsigned m_case_split_factor; //!< the product of the size of the clauses created by this quantifier.
+        unsigned m_num_nested_quantifiers;
+        unsigned m_num_instances;
+        unsigned m_num_instances_curr_search;
+        unsigned m_num_instances_curr_branch; //!< only updated if QI_TRACK_INSTANCES is true
+        unsigned m_max_generation; //!< max. generation of an instance
+        float    m_max_cost;
+
+        friend class quantifier_stat_gen;
+
+        quantifier_stat(unsigned generation);
+    public:
+
+        unsigned get_size() const { 
+            return m_size; 
+        }
+        
+        unsigned get_depth() const { 
+            return m_depth; 
+        }
+        
+        unsigned get_generation() const {
+            return m_generation; 
+        }
+        
+        unsigned get_case_split_factor() const {
+            return m_case_split_factor;
+        }
+
+        unsigned get_num_nested_quantifiers() const {
+            return m_num_nested_quantifiers;
+        }
+
+        unsigned get_num_instances() const {
+            return m_num_instances;
+        }
+
+        unsigned get_num_instances_curr_search() const {
+            return m_num_instances_curr_search;
+        }
+
+        unsigned & get_num_instances_curr_branch() {
+            return m_num_instances_curr_branch;
+        }
+        
+        void inc_num_instances() {
+            m_num_instances++;
+            m_num_instances_curr_search++;
+        }
+
+        void inc_num_instances_curr_branch() {
+            m_num_instances_curr_branch++;
+        }
+
+        void reset_num_instances_curr_search() {
+            m_num_instances_curr_search = 0;
+        }
+
+        void update_max_generation(unsigned g) {
+            if (m_max_generation < g)
+                m_max_generation = g;
+        }
+
+        unsigned get_max_generation() const {
+            return m_max_generation;
+        }
+
+        void update_max_cost(float c) {
+            if (m_max_cost < c)
+                m_max_cost = c;
+        }
+
+        float get_max_cost() const {
+            return m_max_cost;
+        }
+    };
+
+    /**
+       \brief Functor used to generate quantifier statistics.
+    */
+    class quantifier_stat_gen {
+        struct entry {
+            expr *    m_expr;
+            unsigned  m_depth:31;
+            bool      m_depth_only:1; //!< track only the depth of this entry.
+            entry():m_expr(0), m_depth(0), m_depth_only(false) {}
+            entry(expr * n, unsigned depth = 0, bool depth_only = false):m_expr(n), m_depth(depth), m_depth_only(depth_only) {}
+        };
+        ast_manager &           m_manager;
+        region &                m_region;
+        obj_map<expr, unsigned> m_already_found; // expression to the max. depth it was reached.
+        svector<entry>          m_todo;
+        approx_nat              m_case_split_factor;
+        void reset();
+        
+    public:
+        quantifier_stat_gen(ast_manager & m, region & r);
+        quantifier_stat * operator()(quantifier * q, unsigned generation);
+    };
+
+};
+
+#endif /* _SMT_QUANTIFIER_STAT_H_ */
+