add variable replay, remove MacOS from Travis (#4681)

* na

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

* na

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

* na

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

* na

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

* na

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

* na

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

* na

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

* na

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

* dbg

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

* bv

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

* drat and fresh

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

* move ackerman functionality

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

* na

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

* debugability

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

* towards debugability

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

* missing file

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

* na

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

* na

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

* remove csp

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

* replay variables created by solver

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

* remove old function

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

* fix scoped-limit

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

src/sat/smt/bv_ackerman.h

@@ -52,7 +52,8 @@ namespace bv {
         table_t       m_table;
         vv*           m_queue { nullptr };
         vv*           m_tmp_vv { nullptr };
-        unsigned      m_gc_threshold { 1 };
+
+        unsigned      m_gc_threshold { 100 };
         unsigned      m_propagate_high_watermark { 10000 };
         unsigned      m_propagate_low_watermark { 10 };
         unsigned      m_num_propagations_since_last_gc { 0 };

src/sat/smt/euf_ackerman.cpp

@@ -47,6 +47,7 @@ namespace euf {
         inf.b = b;
         inf.c = lca;
         inf.is_cc = false;
+        inf.m_count = 0;
         insert();
     }
 

src/sat/smt/euf_ackerman.h

@@ -57,7 +57,7 @@ namespace euf {
         table_t       m_table;
         inference*    m_queue { nullptr };
         inference*    m_tmp_inference { nullptr };
-        unsigned      m_gc_threshold { 1 };
+        unsigned      m_gc_threshold { 100 };
         unsigned      m_high_watermark { 1000 };
         unsigned      m_num_propagations_since_last_gc { 0 };
  

src/sat/smt/euf_solver.cpp

@@ -315,6 +315,7 @@ namespace euf {
     }
 
     void solver::pop(unsigned n) {
+        start_reinit(n);
         m_egraph.pop(n);
         for (auto* e : m_solvers)
             e->pop(n);
@@ -328,28 +329,32 @@ namespace euf {
     }
 
     void solver::start_reinit(unsigned n) {
-        sat::literal_vector lits;
-        m_reinit_vars.reset();
         m_reinit_exprs.reset();
-        s().get_reinit_literals(n, lits);
-        for (sat::literal lit : lits) {
-            sat::bool_var v = lit.var();
+        for (sat::bool_var v : s().get_vars_to_reinit()) {
             expr* e = bool_var2expr(v);
-            if (m_reinit_vars.contains(v) || !e)
-                continue;
-            m_reinit_vars.push_back(v);
             m_reinit_exprs.push_back(e);
         }
     }
 
     void solver::finish_reinit() {
-        unsigned sz = m_reinit_vars.size();
-        for (unsigned i = 0; i < sz; ++i) {
-            euf::enode* n = get_enode(m_reinit_exprs.get(i));
-            if (n)
-                continue;
 
+        SASSERT(s().get_vars_to_reinit().size() == m_reinit_exprs.size());
+        if (s().get_vars_to_reinit().empty())
+            return;
+        unsigned i = 0;
+        obj_map<expr, sat::bool_var> expr2var_replay;
+        for (sat::bool_var v : s().get_vars_to_reinit()) {
+            expr* e = m_reinit_exprs.get(i++);
+            if (!e)
+                continue;
+            expr2var_replay.insert(e, v);
         }
+        if (expr2var_replay.empty())
+            return;
+        si.set_expr2var_replay(&expr2var_replay);
+        for (auto const& kv : expr2var_replay)
+            si.internalize(kv.m_key, true);
+        si.set_expr2var_replay(nullptr);        
     }
 
     void solver::pre_simplify() {
@@ -461,6 +466,7 @@ namespace euf {
     }
 
     void solver::pop_reinit() {
+        finish_reinit();
         for (auto* e : m_solvers)
             e->pop_reinit();
     }

src/sat/smt/euf_solver.h

@@ -118,7 +118,6 @@ namespace euf {
 
         // replay
         expr_ref_vector      m_reinit_exprs;
-        sat::bool_var_vector m_reinit_vars;
         
         void start_reinit(unsigned num_scopes);
         void finish_reinit();

src/sat/smt/sat_smt.h

@@ -44,6 +44,7 @@ namespace sat {
         virtual void cache(app* t, literal l) = 0;
         virtual void push() = 0;
         virtual void pop(unsigned n) = 0;
+        virtual void set_expr2var_replay(obj_map<expr, sat::bool_var>* r) = 0;
     };
     
     class constraint_base {