+
+ let module WeightOrderedPassives =
+ struct
+ type t = B.t Terms.passive_clause
+
+ let compare = Utils.compare_passive_clauses_weight
+ end
+ in
+ let module AgeOrderedPassives =
+ struct
+ type t = B.t Terms.passive_clause
+
+ let compare = Utils.compare_passive_clauses_age
+ end
+ in
+ let module WeightPassiveSet = Set.Make(WeightOrderedPassives) in
+ let module AgePassiveSet = Set.Make(AgeOrderedPassives) in
+ let add_passive_clause ?(no_weight=false) (passives_w,passives_a) cl =
+ let cl = if no_weight then (0,cl)
+ else Utils.mk_passive_clause cl in
+ WeightPassiveSet.add cl passives_w, AgePassiveSet.add cl passives_a
+ in
+ let remove_passive_clause (passives_w,passives_a) cl =
+ let passives_w = WeightPassiveSet.remove cl passives_w in
+ let passives_a = AgePassiveSet.remove cl passives_a in
+ passives_w,passives_a
+ in
+ let add_passive_clauses (passives_w,passives_a) new_clauses =
+ let new_clauses_w,new_clauses_a = List.fold_left add_passive_clause
+ (WeightPassiveSet.empty,AgePassiveSet.empty) new_clauses
+ in
+ (WeightPassiveSet.union new_clauses_w passives_w,
+ AgePassiveSet.union new_clauses_a passives_a)
+ in
+ let is_passive_set_empty (passives_w,passives_a) =
+ if (WeightPassiveSet.is_empty passives_w) then begin
+ assert (AgePassiveSet.is_empty passives_a); true
+ end else begin
+ assert (not (AgePassiveSet.is_empty passives_a)); false
+ end
+ in
+ let passive_set_cardinal (passives_w,_) =
+ WeightPassiveSet.cardinal passives_w
+ in
+ let passive_singleton cl =
+ (WeightPassiveSet.singleton cl,AgePassiveSet.singleton cl)
+ in
+ let passive_empty_set =
+ (WeightPassiveSet.empty,AgePassiveSet.empty)
+ in
+ let pick_min_passive use_age (passives_w,passives_a) =
+ if use_age then AgePassiveSet.min_elt passives_a
+ else WeightPassiveSet.min_elt passives_w
+ in
+ let timeout = Unix.gettimeofday () +. amount_of_time in
+
+ (* TODO : global age over facts and goals (without comparing weights) *)
+ let select passives g_passives =
+ if is_passive_set_empty passives then begin
+ assert (not (is_passive_set_empty g_passives));
+ let g_cl = pick_min_passive false g_passives in
+ (true,snd g_cl,passives,remove_passive_clause g_passives g_cl)
+ end
+ else let cl = pick_min_passive false passives in
+ if is_passive_set_empty g_passives then
+ (false,snd cl,remove_passive_clause passives cl,g_passives)
+ else
+ let g_cl = pick_min_passive false g_passives in
+ if (fst cl <= fst g_cl) then
+ (false,snd cl,remove_passive_clause passives cl,g_passives)
+ else
+ (true,snd g_cl,passives,remove_passive_clause g_passives g_cl)
+ in
+
+ let backward_infer_step bag maxvar actives passives
+ g_actives g_passives g_current =
+ (* superposition left, simplifications on goals *)
+ debug "infer_left step...";
+ let bag, maxvar, new_goals =
+ Sup.infer_left bag maxvar g_current actives
+ in
+ debug "Performed infer_left step";
+ bag, maxvar, actives, passives, g_current::g_actives,
+ (add_passive_clauses g_passives new_goals)
+ in
+
+ let forward_infer_step bag maxvar actives passives g_actives
+ g_passives current =
+ (* forward step *)
+
+ (* e = select P *
+ * e' = demod A e *
+ * A' = demod [e'] A *
+ * A'' = A' + e' *
+ * e'' = fresh e' *
+ * new = supright e'' A'' *
+ * new'= demod A'' new *
+ * P' = P + new' *)
+ debug "Forward infer step...";
+ debug "Selected and simplified";
+ (* debug ("Fact after simplification :"
+ ^ Pp.pp_unit_clause current); *)
+ let bag, maxvar, actives, new_clauses =
+ Sup.infer_right bag maxvar current actives
+ in
+ debug "Demodulating goals with actives...";
+ (* keep goals demodulated w.r.t. actives and check if solved *)
+ let bag, g_actives =
+ List.fold_left
+ (fun (bag,acc) c ->
+ match Sup.simplify_goal maxvar (snd actives) bag acc c with
+ | None -> bag, acc
+ | Some (bag,c) -> bag,c::acc)
+ (bag,[]) g_actives
+ in
+ let ctable = IDX.index_unit_clause IDX.DT.empty current in
+ let bag, maxvar, new_goals =
+ List.fold_left
+ (fun (bag,m,acc) g ->
+ let bag, m, ng = Sup.infer_left bag m g
+ ([current],ctable) in
+ bag,m,ng@acc)
+ (bag,maxvar,[]) g_actives
+ in
+ bag, maxvar, actives,
+ add_passive_clauses passives new_clauses, g_actives,
+ add_passive_clauses g_passives new_goals
+ in
+
+ let rec given_clause bag maxvar actives passives g_actives g_passives =
+ (* prerr_endline "Bag :"; prerr_endline (Pp.pp_bag bag);
+ prerr_endline "Active table :";
+ (List.iter (fun x -> prerr_endline (Pp.pp_unit_clause x))
+ (fst actives)); *)
+ incr nb_iter; if !nb_iter = max_nb_iter then
+ raise (Failure "No iterations left !");
+ if Unix.gettimeofday () > timeout then
+ raise (Failure "Timeout !");
+
+
+ let rec aux_select passives g_passives =
+ let backward,current,passives,g_passives = select passives g_passives in
+ if backward then
+ match Sup.simplify_goal maxvar (snd actives) bag g_actives current with
+ | None -> aux_select passives g_passives
+ | Some x -> let bag,g_current = x in
+ backward_infer_step bag maxvar actives passives
+ g_actives g_passives g_current
+ else
+ (* debug ("Selected fact : " ^ Pp.pp_unit_clause current); *)
+ match Sup.keep_simplified current actives bag maxvar with
+ (* match Sup.one_pass_simplification current actives bag maxvar with*)
+ | None -> aux_select passives g_passives
+ | Some x -> let (current, bag, actives) = x in
+ forward_infer_step bag maxvar actives passives
+ g_actives g_passives current
+ in
+
+ let bag,maxvar,actives,passives,g_actives,g_passives =
+ aux_select passives g_passives
+ in
+ debug
+ (Printf.sprintf "Number of active goals : %d"
+ (List.length g_actives));
+ debug
+ (Printf.sprintf "Number of passive goals : %d"
+ (passive_set_cardinal g_passives));
+ debug
+ (Printf.sprintf "Number of actives : %d" (List.length (fst actives)));
+ debug
+ (Printf.sprintf "Number of passives : %d"
+ (passive_set_cardinal passives));
+ given_clause bag maxvar actives passives g_actives g_passives
+ in
+
+ let mk_clause ?(no_weight=false) bag maxvar (t,ty) =
+ let (proof,ty) = B.saturate t ty in
+ let c, maxvar = Utils.mk_unit_clause maxvar ty proof in
+ let bag, c = Utils.add_to_bag bag c in
+ bag, maxvar, c
+ in
+ let bag, maxvar, goal = mk_clause Terms.M.empty 0 t in
+ let g_actives = [] in
+ let g_passives =
+ passive_singleton (0,goal)
+ in
+ let passives, bag, maxvar =