perf: remove useless copy of process states (/10 memory on some examples!)

lib/sasacore/simuState.ml

-(* Time-stamp: <modified the 20/05/2021 (at 09:09) by Erwan Jahier> *)
+(* Time-stamp: <modified the 23/07/2021 (at 11:19) by Erwan Jahier> *)
 
 open Register
 
@@ -60,9 +60,10 @@ let (neigbors_of_pid : 'v t -> pid -> 's * ('s neighbor * pid) list) =
   Env.get st.config pid,  List.map (fun n -> n, n.Register.pid) nl
 
   
-let (update_neighbor_env: 'v Env.t -> 'v Register.neighbor list -> 'v Register.neighbor list) =
+let (update_neighbor_env:
+       'v Env.t -> 'v Register.neighbor list -> 'v Register.neighbor list) =
   fun e nl ->
-  List.map (fun n -> { n with state = Env.get_copy e n.Register.pid }) nl
+  List.map (fun n -> { n with state = Env.get e n.Register.pid }) nl
 
 let update_neighbors config neighbors = StringMap.map
     (fun nl -> update_neighbor_env config nl)
@@ -84,14 +85,7 @@ let (get_enable_processes: 'v t -> 'v enable_processes) =
   assert (pl_n <> []);
   let all = List.fold_left
       (fun acc (p,nl) ->
-         (* let nl0 = nl in *)
-         (* let nl = update_neighbor_env e nl in (* already done? *) *)
-         (*  if  List.exists2 (fun n1 n2 ->  (n1.state <> n2.state)) nl nl0 then ( *)
-         (*   dump_process "avant" (p,nl0); *)
-         (*   dump_process "apres" (p,nl); *)
-         (*   assert false *)
-         (*          ); *)
-         let lenv = Env.get_copy e p.pid in
+         let lenv = Env.get e p.pid in
          let al = p.enable nl lenv in
          let al =
            List.map (fun a ->