Set states without children to Sat early

We can set states without children to Sat right after we expand them.

src/lib/CoAlgReasoner.ml

@@ -1114,14 +1114,22 @@ let rec insertAllRules state rules =
   List.mem true (List.map (fun (dep, children) -> insertRule state dep children) rules)
 
 let expandState state =
+  let setSatOrOpen () =
+    if CU.TList.empty (stateGetRules state) then
+      stateSetStatus state Sat
+    else
+      stateSetStatus state Open
+  in
+
   match stateNextRule state with
   | MultipleElements rules ->
       let unsat = insertAllRules state rules in
-      if not unsat then stateSetStatus state Open
+      if not unsat then setSatOrOpen ()
   | SingleElement (dep, chldrn) ->
       let unsat = insertRule state dep chldrn in
       if not unsat then queueInsertState state else ()
-  | NoMoreElements -> stateSetStatus state Open
+  | NoMoreElements ->
+     setSatOrOpen ()
 
 
 let expandCnstr cset =