add parameter to force sat-cleaning on initialization and on simplification phases

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

src/sat/sat_config.cpp

@@ -152,6 +152,8 @@ namespace sat {
         m_gc_burst        = p.gc_burst();
         m_gc_defrag       = p.gc_defrag();
 
+        m_force_cleanup   = p.force_cleanup();
+
         m_minimize_lemmas = p.minimize_lemmas();
         m_core_minimize   = p.core_minimize();
         m_core_minimize_partial   = p.core_minimize_partial();

src/sat/sat_config.h

@@ -136,6 +136,8 @@ namespace sat {
         bool               m_gc_burst;
         bool               m_gc_defrag;
 
+        bool               m_force_cleanup;
+
 
         bool               m_minimize_lemmas;
         bool               m_dyn_sub_res;

src/sat/sat_params.pyg

@@ -31,6 +31,7 @@ def_module_params('sat',
                           ('gc.burst', BOOL, False, 'perform eager garbage collection during initialization'),
                           ('gc.defrag', BOOL, True, 'defragment clauses when garbage collecting'),
                           ('simplify.delay', UINT, 0, 'set initial delay of simplification by a conflict count'),
+                          ('force_cleanup', BOOL, False, 'force cleanup to remove tautologies and simplify clauses'),
                           ('minimize_lemmas', BOOL, True, 'minimize learned clauses'),
                           ('dyn_sub_res', BOOL, True, 'dynamic subsumption resolution for minimizing learned clauses'),
                           ('core.minimize', BOOL, False, 'minimize computed core'),

src/sat/sat_solver.cpp

@@ -1086,7 +1086,7 @@ namespace sat {
             init_assumptions(num_lits, lits);
             propagate(false);
             if (check_inconsistent()) return l_false;
-            cleanup();
+            cleanup(m_config.m_force_cleanup);
 
             if (m_config.m_unit_walk) {
                 return do_unit_walk();
@@ -1458,7 +1458,7 @@ namespace sat {
         if (should_restart()) 
             return l_undef;
         if (at_base_lvl()) {
-            cleanup(); // cleaner may propagate frozen clauses
+            cleanup(false); // cleaner may propagate frozen clauses
             if (inconsistent()) {
                 TRACE("sat", tout << "conflict at level 0\n";);
                 return l_false;
@@ -1654,7 +1654,7 @@ namespace sat {
 
         SASSERT(at_base_lvl());
 
-        m_cleaner();
+        m_cleaner(m_config.m_force_cleanup);
         CASSERT("sat_simplify_bug", check_invariant());
 
         m_scc();
@@ -3695,10 +3695,10 @@ namespace sat {
     // Simplification
     //
     // -----------------------
-    void solver::cleanup() {
+    void solver::cleanup(bool force) {
         if (!at_base_lvl() || inconsistent())
             return;
-        if (m_cleaner() && m_ext)
+        if (m_cleaner(force) && m_ext)
             m_ext->clauses_modifed();
     }
 

src/sat/sat_solver.h

@@ -549,7 +549,7 @@ namespace sat {
         //
         // -----------------------
     public:
-        void cleanup();
+        void cleanup(bool force);
         void simplify(bool learned = true);
         void asymmetric_branching();
         unsigned scc_bin();