(* LOOPING : COL057-1.ma *)
let debug s =
- () (* prerr_endline s *)
+ prerr_endline s
;;
let nparamod rdb metasenv subst context t table =
PassiveSet.add (Utils.mk_passive_clause cl) passives
in
let timeout = Unix.gettimeofday () +. amount_of_time in
+
(* TODO : fairness condition *)
- let select passives =
- if PassiveSet.is_empty passives then None
+ let select passives g_passives =
+ if PassiveSet.is_empty passives then begin
+ assert (not (PassiveSet.is_empty g_passives));
+ let g_cl = PassiveSet.min_elt g_passives in
+ (true,snd g_cl,passives,PassiveSet.remove g_cl g_passives)
+ end
else let cl = PassiveSet.min_elt passives in
- Some (snd cl,PassiveSet.remove cl passives)
+ if PassiveSet.is_empty g_passives then
+ (false,snd cl,PassiveSet.remove cl passives,g_passives)
+ else
+ let g_cl = PassiveSet.min_elt g_passives in
+ if (fst cl <= fst g_cl) then
+ (false,snd cl,PassiveSet.remove cl passives,g_passives)
+ else
+ (true,snd g_cl,passives,PassiveSet.remove g_cl g_passives)
+ in
+
+ let backward_infer_step bag maxvar actives passives g_actives g_passives g_current =
+ (* superposition left, simplifications on goals *)
+ debug "infer_left step...";
+ debug ("Selected goal : " ^ Pp.pp_unit_clause g_current);
+ let bag, g_current =
+ Sup.simplify_goal maxvar (snd actives) bag g_current
+ in
+ debug "Simplified goal";
+ let bag, maxvar, new_goals =
+ Sup.infer_left bag maxvar g_current actives
+ in
+ debug "Performed infer_left step";
+ let new_goals = List.fold_left add_passive_clause
+ PassiveSet.empty new_goals
+ in
+ bag, maxvar, actives, passives, g_current::g_actives,
+ (PassiveSet.union new_goals g_passives)
+ 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...";
+ debug ("Current : " ^ (Pp.pp_unit_clause current));
+ debug ("Active goal : " ^ (Pp.pp_unit_clause (List.hd g_actives)));
+ (* keep goals demodulated w.r.t. actives and check if solved *)
+ let bag, g_actives =
+ List.fold_left
+ (fun (bag,acc) c ->
+ let bag, c = Sup.simplify_goal maxvar (snd actives) bag c in
+ bag, c::acc)
+ (bag,[]) g_actives
+ in
+ debug (Pp.pp_unit_clause current);
+ debug (Pp.pp_unit_clause (List.hd g_actives));
+ 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
+ let new_clauses = List.fold_left add_passive_clause
+ PassiveSet.empty new_clauses in
+ let new_goals = List.fold_left add_passive_clause
+ PassiveSet.empty new_goals in
+ debug (string_of_int (PassiveSet.cardinal new_goals));
+ debug (string_of_int (PassiveSet.cardinal g_passives));
+ bag, maxvar, actives,
+ PassiveSet.union new_clauses passives, g_actives,
+ PassiveSet.union new_goals g_passives
in
- let rec given_clause bag maxvar actives
- passives g_actives g_passives =
+
+ 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))
raise (Failure "Timeout !");
-
- (* superposition left, simplifications on goals *)
- debug "infer_left step...";
- let bag, maxvar, g_actives, g_passives =
- match select g_passives with
- | None -> bag, maxvar, g_actives, g_passives
- | Some (g_current, g_passives) ->
- debug ("Selected goal : " ^ Pp.pp_unit_clause g_current);
- let bag, g_current =
- Sup.simplify_goal maxvar (snd actives) bag g_current
- in
- debug "Simplified goal";
- let bag, maxvar, new_goals =
- Sup.infer_left bag maxvar g_current actives
- in
- debug "Performed infer_left step";
- let new_goals = List.fold_left add_passive_clause
- PassiveSet.empty new_goals
- in
- bag, maxvar, g_current::g_actives,
- (PassiveSet.union new_goals g_passives)
+ let rec aux_select passives g_passives =
+ let backward,current,passives,g_passives = select passives g_passives in
+ if backward then
+ backward_infer_step bag maxvar actives passives
+ g_actives g_passives 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
+ assert (PassiveSet.cardinal g_passives < 2);
debug
(Printf.sprintf "Number of active goals : %d"
(List.length g_actives));
debug
(Printf.sprintf "Number of passive goals : %d"
(PassiveSet.cardinal g_passives));
-
- (* 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...";
- let bag, maxvar, actives, passives, g_passives =
- let rec aux_simplify passives =
- match select passives with
- | None -> assert false
- | Some (current, passives) ->
- 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_simplify passives
- | Some x -> x,passives
- in
- let (current, bag, actives),passives = aux_simplify passives
- in
- 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 ->
- let bag, c = Sup.simplify_goal maxvar (snd actives) bag c in
- 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
- let new_clauses = List.fold_left add_passive_clause
- PassiveSet.empty new_clauses in
- let new_goals = List.fold_left add_passive_clause
- PassiveSet.empty new_goals in
- bag, maxvar, actives,
- PassiveSet.union new_clauses passives,
- PassiveSet.union new_goals g_passives
- in
debug
(Printf.sprintf "Number of actives : %d" (List.length (fst actives)));
debug