Reorganizing the code

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

src/sat/sat_clause_use_list.h

@@ -0,0 +1,118 @@
+/*++
+Copyright (c) 2011 Microsoft Corporation
+
+Module Name:
+
+    sat_clause_use_list.h
+
+Abstract:
+
+    Clause use list
+
+Author:
+
+    Leonardo de Moura (leonardo) 2011-05-31.
+
+Revision History:
+
+--*/
+#ifndef _SAT_CLAUSE_USE_LIST_H_
+#define _SAT_CLAUSE_USE_LIST_H_
+
+#include"sat_types.h"
+
+namespace sat {
+
+#define LAZY_USE_LIST
+
+    /**
+       \brief Clause use list with delayed deletion.
+    */
+    class clause_use_list {
+        clause_vector   m_clauses;
+#ifdef LAZY_USE_LIST
+        unsigned        m_size;
+#endif
+    public:
+        clause_use_list() {
+#ifdef LAZY_USE_LIST
+            m_size = 0; 
+#endif
+        }
+        
+        unsigned size() const { 
+#ifdef LAZY_USE_LIST
+            return m_size; 
+#else
+            return m_clauses.size();
+#endif
+        }
+
+        bool empty() const { return size() == 0; }
+        
+        void insert(clause & c) { 
+            SASSERT(!m_clauses.contains(&c)); SASSERT(!c.was_removed()); 
+            m_clauses.push_back(&c); 
+#ifdef LAZY_USE_LIST
+            m_size++; 
+#endif
+        }
+        void erase_not_removed(clause & c) { 
+#ifdef LAZY_USE_LIST
+            SASSERT(m_clauses.contains(&c)); SASSERT(!c.was_removed()); m_clauses.erase(&c); m_size--; 
+#else
+            m_clauses.erase(&c);
+#endif
+        }
+        void erase(clause & c) { 
+#ifdef LAZY_USE_LIST
+            SASSERT(m_clauses.contains(&c)); SASSERT(c.was_removed()); m_size--; 
+#else
+            m_clauses.erase(&c);
+#endif
+        }
+        
+        void reset() { 
+            m_clauses.finalize(); 
+#ifdef LAZY_USE_LIST
+            m_size = 0; 
+#endif
+        }
+        
+        bool check_invariant() const;
+        // iterate & compress
+        class iterator {
+            clause_vector & m_clauses;
+            unsigned        m_size;
+            unsigned        m_i;
+#ifdef LAZY_USE_LIST
+            unsigned        m_j;
+            void consume();
+#endif
+        public:
+            iterator(clause_vector & v):m_clauses(v), m_size(v.size()), m_i(0) {
+#ifdef LAZY_USE_LIST
+                m_j = 0;
+                consume(); 
+#endif
+            }
+            ~iterator();
+            bool at_end() const { return m_i == m_size; }
+            clause & curr() const { SASSERT(!at_end()); return *(m_clauses[m_i]); }
+            void next() { 
+                SASSERT(!at_end()); 
+                SASSERT(!m_clauses[m_i]->was_removed()); 
+                m_i++; 
+#ifdef LAZY_USE_LIST
+                m_j++; 
+                consume(); 
+#endif
+            }
+        };
+        
+        iterator mk_iterator() const { return iterator(const_cast<clause_use_list*>(this)->m_clauses); }
+    };
+
+};
+
+#endif