Z3 sources

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

lib/act_cache.h

@@ -0,0 +1,56 @@
+/*++
+Copyright (c) 2011 Microsoft Corporation
+
+Module Name:
+
+    act_cache.h
+
+Abstract:
+
+    expr -> expr activity cache
+    It maintains at most N unused entries
+
+Author:
+
+    Leonardo (leonardo) 2011-04-12
+
+Notes:
+
+--*/
+#ifndef _ACT_CACHE_H_
+#define _ACT_CACHE_H_
+
+#include"ast.h"
+#include"obj_hashtable.h"
+#include"chashtable.h"
+
+class act_cache {
+    ast_manager &        m_manager;
+    typedef cmap<expr*, expr*, obj_ptr_hash<expr>, default_eq<expr*> > map;
+    map                  m_table;
+    ptr_vector<expr>     m_queue; // recently created queue
+    unsigned             m_qhead;
+    unsigned             m_unused;
+    unsigned             m_max_unused;
+
+    void compress_queue();
+    void init();
+    void dec_refs();
+    void del_unused();
+
+public:
+    act_cache(ast_manager & m);
+    act_cache(ast_manager & m, unsigned max_unused);
+    ~act_cache();
+    void insert(expr * k, expr * v);
+    expr * find(expr * k);
+    void reset();
+    void cleanup();
+    unsigned size() const { return m_table.size(); }
+    unsigned capacity() const { return m_table.capacity(); }
+    bool empty() const { return m_table.empty(); }
+    bool check_invariant() const;
+    
+};
+
+#endif