+
+ (* we just check if any of the active goals is subsumed by a
+ passive clause, or if any of the passive goal is subsumed
+ by an active or passive clause *)
+ let last_chance (bag,maxvar,actives,passives,g_actives,g_passives) =
+ debug (lazy("Last chance " ^ string_of_float
+ (Unix.gettimeofday())));
+ let active_t = snd actives in
+ let passive_t,wset,_ = passives in
+ let _ = debug
+ (lazy
+ ("Passive set :" ^ (String.concat ";\n"
+ (List.map (fun _,cl -> Pp.pp_unit_clause cl)
+ (WeightPassiveSet.elements wset))))) in
+ let wset = IDX.elems passive_t in
+ let _ = debug
+ (lazy
+ ("Passive table :" ^(String.concat ";\n"
+ (List.map (fun _,cl -> Pp.pp_unit_clause cl)
+ (IDX.ClauseSet.elements wset))))) in
+ let g_passives =
+ WeightPassiveSet.fold
+ (fun (_,x) acc ->
+ if List.exists (Sup.are_alpha_eq x) g_actives then acc
+ else x::acc)
+ (fst g_passives) []
+ in
+ ignore
+ (List.iter
+ (fun x ->
+ ignore
+ (Sup.simplify_goal ~no_demod:true maxvar active_t bag [] x))
+ g_passives);
+ ignore
+ (List.iter
+ (fun x ->
+ ignore
+ (Sup.simplify_goal ~no_demod:true maxvar passive_t bag [] x))
+ (g_actives@g_passives));
+ raise (Stop (Timeout (maxvar,bag)))
+
+ let check_timeout = function
+ | None -> false
+ | Some timeout -> Unix.gettimeofday () > timeout
+
+ let rec given_clause ~useage
+ bag maxvar iterno weight_picks max_steps timeout
+ actives passives g_actives g_passives
+ =
+ let iterno = iterno + 1 in
+ if iterno = max_steps || check_timeout timeout then
+ last_chance (bag,maxvar,actives,passives,g_actives,g_passives)
+ else
+ let use_age = useage && (weight_picks = (iterno / 6 + 1)) in
+ let weight_picks = if use_age then 0 else weight_picks+1
+ in
+
+ let rec aux_select bag
+ (passives:IDX.DT.t * WeightPassiveSet.t * AgePassiveSet.t)
+ g_passives =
+ let backward,(weight,current),passives,g_passives =
+ select ~use_age passives g_passives
+ in
+ if use_age && weight > monster then
+ let bag,cl = Terms.add_to_bag current bag in
+ if backward then
+ aux_select bag passives (add_passive_goal g_passives cl)
+ else
+ aux_select bag (add_passive_clause passives cl) g_passives
+ else
+ let bag = Terms.replace_in_bag (current,false,iterno) bag in
+ if backward then
+ let _ = debug (lazy("Selected goal : " ^ Pp.pp_unit_clause current)) in
+ match
+ Sup.simplify_goal
+ ~no_demod:false maxvar (snd actives) bag g_actives current
+ with
+ | None -> aux_select bag passives g_passives
+ | Some (bag,g_current) ->
+ backward_infer_step bag maxvar actives passives
+ g_actives g_passives g_current iterno
+ else
+ let _ = debug (lazy("Selected fact : " ^ Pp.pp_unit_clause current))
+ in
+ if Sup.orphan_murder bag (fst actives) current then
+ let _ = debug (lazy "Orphan murdered") in
+ let bag = Terms.replace_in_bag (current,true,iterno) bag in
+ aux_select bag passives g_passives
+ else
+ let s = bag,maxvar,actives,passives,g_actives,g_passives in
+ let s1 = forward_infer_step s current iterno
+ in
+ if s == s1 then aux_select bag passives g_passives
+ else s1
+ in
+ (*prerr_endline "Active table :";
+ (List.iter (fun x -> prerr_endline (Pp.pp_unit_clause x))
+ (fst actives)); *)
+
+ let (bag,maxvar,actives,passives,g_actives,g_passives) as status =
+ aux_select bag passives g_passives
+ in
+ debug (debug_status status);
+ given_clause ~useage
+ bag maxvar iterno weight_picks max_steps timeout
+ actives passives g_actives g_passives
+ ;;
+
+ (* similar to given_clause, but it merely works on goals,
+ in parallel, at each iteration *)
+ let rec goal_narrowing iterno max_steps timeout status
+ =
+ debug (debug_status status);
+ let iterno = iterno + 1 in
+ if iterno = max_steps || check_timeout timeout then
+ last_chance status
+ else
+ let _,_,_,_,_,g_passives = status in
+ let passive_goals = WeightPassiveSet.elements (fst g_passives) in
+ let newstatus =
+ List.fold_left
+ (fun acc g ->
+ let bag,maxvar,actives,passives,g_actives,g_passives = acc in
+ let g_passives =
+ remove_passive_goal g_passives g in
+ let current = snd g in
+ let _ =
+ debug (lazy("Selected goal : " ^ Pp.pp_unit_clause current))
+ in
+ match
+ Sup.simplify_goal
+ ~no_demod:false maxvar (snd actives) bag g_actives current
+ with
+ | None -> acc
+ | Some (bag,g_current) ->
+ let _ =
+ debug (lazy("Demodulated goal : "
+ ^ Pp.pp_unit_clause g_current))
+ in
+ backward_infer_step bag maxvar actives passives
+ g_actives g_passives g_current iterno)
+ status passive_goals
+ in
+ goal_narrowing iterno max_steps timeout newstatus
+
+ let compute_result bag i subst =
+ let l =
+ let rec traverse ongoal (accg,acce) i =
+ match Terms.get_from_bag i bag with
+ | (id,_,_,Terms.Exact _),_,_ ->
+ if ongoal then [i],acce else
+ if (List.mem i acce) then accg,acce else accg,acce@[i]
+ | (_,_,_,Terms.Step (_,i1,i2,_,_,_)),_,_ ->
+ if (not ongoal) && (List.mem i acce) then accg,acce
+ else
+ let accg,acce =
+ traverse false (traverse ongoal (accg,acce) i1) i2
+ in
+ if ongoal then i::accg,acce else accg,i::acce
+ in
+ let gsteps,esteps = traverse true ([],[]) i in
+ (List.rev esteps)@gsteps
+ in
+ debug (lazy ("steps: " ^ (string_of_int (List.length l))));
+ let max_w =
+ List.fold_left
+ (fun acc i ->
+ let (cl,_,_) = Terms.get_from_bag i bag in
+ max acc (Order.compute_unit_clause_weight cl)) 0 l in
+ debug (lazy ("Max weight : " ^ (string_of_int max_w)));
+(* List.iter (fun id -> let ((_,lit,_,proof as cl),d,it) =
+ Terms.get_from_bag id bag in
+ if d then
+ prerr_endline
+ (Printf.sprintf "Id : %d, selected at %d, weight %d,disc, by %s"
+ id it (Order.compute_unit_clause_weight cl)
+ (Pp.pp_proof_step proof))
+ else
+ prerr_endline
+ (Printf.sprintf "Id : %d, selected at %d, weight %d by %s"
+ id it (Order.compute_unit_clause_weight cl)
+ (Pp.pp_proof_step proof))) l;*)
+ debug (lazy ("Proof:" ^
+ (String.concat "\n"
+ (List.map
+ (fun x ->
+ let cl,_,_ = Terms.get_from_bag x bag in
+ Pp.pp_unit_clause cl) l))));
+ Unsatisfiable [ bag, i, subst, l ]
+
+ let paramod ~useage ~max_steps ?timeout (bag,maxvar) ~g_passives ~passives =
+ let _initial_timestamp = Unix.gettimeofday () in
+ let passives =
+ add_passive_clauses ~no_weight:true passive_empty_set passives
+ in
+ let g_passives =
+ add_passive_goals ~no_weight:true g_passive_empty_set g_passives
+ in
+ let g_actives = [] in
+ let actives = [], IDX.DT.empty in
+ try
+ given_clause ~useage ~noinfer:false
+ bag maxvar 0 0 max_steps timeout actives passives g_actives g_passives
+ with
+ | Sup.Success (bag, _, (i,_,_,_),subst) ->
+ compute_result bag i subst
+ | Stop (Unsatisfiable _) -> Error "solution found!"
+ | Stop o -> o
+ ;;
+
+let fast_eq_check s goal =
+ let (_,_,_,_,_,g_passives) as s = initialize_goal s goal in
+ if is_passive_g_set_empty g_passives then Error "not an equation"
+ else
+ try
+ goal_narrowing 0 2 None s
+ with
+ | Sup.Success (bag, _, (i,_,_,_),subst) ->
+ compute_result bag i subst
+ | Stop (Unsatisfiable _) -> Error "solution found!"
+ | Stop o -> o
+ ;;
+
+end