X-Git-Url: http://matita.cs.unibo.it/gitweb/?a=blobdiff_plain;f=helm%2Fsoftware%2Fcomponents%2Fng_paramodulation%2Fsuperposition.ml;h=c1d5f8bdcffcd9ab3d7a2f226a278e0afe4c6440;hb=772def9075b7b62870ebf4cecec6bcd37a549b1d;hp=c1c0612b1e39d39c7b166357670a3fc9c180b01d;hpb=2f1f71b7b0dbb7dfaea5fd21a2c56c601269ddd4;p=helm.git diff --git a/helm/software/components/ng_paramodulation/superposition.ml b/helm/software/components/ng_paramodulation/superposition.ml index c1c0612b1..c1d5f8bdc 100644 --- a/helm/software/components/ng_paramodulation/superposition.ml +++ b/helm/software/components/ng_paramodulation/superposition.ml @@ -15,14 +15,14 @@ module Superposition (B : Terms.Blob) = struct module IDX = Index.Index(B) module Unif = FoUnif.Founif(B) - module Subst = FoSubst (*.Subst(B)*) + module Subst = FoSubst module Order = Orderings.Orderings(B) module Utils = FoUtils.Utils(B) module Pp = Pp.Pp(B) exception Success of B.t Terms.bag * int * B.t Terms.unit_clause -(* let debug s = prerr_endline s;;*) + let debug s = prerr_endline s;; let debug _ = ();; let rec list_first f = function @@ -31,12 +31,16 @@ module Superposition (B : Terms.Blob) = ;; let first_position pos ctx t f = + let inject_pos pos ctx = function + | None -> None + | Some (a,b,c,d,e) -> Some(ctx a,b,c,d,e,pos) + in let rec aux pos ctx = function - | Terms.Leaf _ as t -> f t pos ctx + | Terms.Leaf _ as t -> inject_pos pos ctx (f t) | Terms.Var _ -> None | Terms.Node l as t-> - match f t pos ctx with - | Some _ as x -> x + match f t with + | Some _ as x -> inject_pos pos ctx x | None -> let rec first pre post = function | [] -> None @@ -72,6 +76,29 @@ module Superposition (B : Terms.Blob) = aux pos ctx t ;; + let parallel_positions bag pos ctx id t f = + let rec aux bag pos ctx id = function + | Terms.Leaf _ as t -> f bag t pos ctx id + | Terms.Var _ as t -> bag,t,id + | Terms.Node l as t-> + let bag,t,id1 = f bag t pos ctx id in + if id = id1 then + let bag, l, _, id = + List.fold_left + (fun (bag,pre,post,id) t -> + let newctx = fun x -> ctx (Terms.Node (pre@[x]@post)) in + let newpos = (List.length pre)::pos in + let bag,newt,id = aux bag newpos newctx id t in + if post = [] then bag, pre@[newt], [], id + else bag, pre @ [newt], List.tl post, id) + (bag, [], List.tl l, id) l + in + bag, Terms.Node l, id + else bag,t,id1 + in + aux bag pos ctx id t + ;; + let vars_of_term t = let rec aux acc = function | Terms.Leaf _ -> acc @@ -92,7 +119,7 @@ module Superposition (B : Terms.Blob) = | t -> Terms.Predicate t in let bag, uc = - Utils.add_to_bag bag (0, literal, vars_of_term t, proof) + Terms.add_to_bag (0, literal, vars_of_term t, proof) bag in Some (bag, uc) else @@ -102,7 +129,7 @@ module Superposition (B : Terms.Blob) = (* ============ simplification ================= *) - let demod table varlist subterm pos context = + let demod table varlist subterm = let cands = IDX.DT.retrieve_generalizations table subterm in list_first (fun (dir, (id,lit,vl,_)) -> @@ -114,26 +141,25 @@ module Superposition (B : Terms.Blob) = let subst, varlist = Unif.unification (varlist@vl) varlist subterm side in + let side = Subst.apply_subst subst side in + let newside = Subst.apply_subst subst newside in if o = Terms.Incomparable then - let side = Subst.apply_subst subst side in - let newside = Subst.apply_subst subst newside in let o = Order.compare_terms newside side in (* Riazanov, pp. 45 (ii) *) if o = Terms.Lt then - Some (context newside, subst, varlist, id, pos, dir) + Some (newside, subst, varlist, id, dir) else ((*prerr_endline ("Filtering: " ^ Pp.pp_foterm side ^ " =(< || =)" ^ Pp.pp_foterm newside ^ " coming from " ^ Pp.pp_unit_clause uc );*)None) else - Some (context newside, subst, varlist, id, pos, dir) + Some (newside, subst, varlist, id, dir) with FoUnif.UnificationFailure _ -> None) (IDX.ClauseSet.elements cands) ;; - let demodulate_once ~jump_to_right bag (id, literal, vl, pr) table = - (* debug ("Demodulating : " ^ (Pp.pp_unit_clause (id, literal, vl, pr)));*) + let demodulate_once_old ~jump_to_right bag (id, literal, vl, pr) table = match literal with | Terms.Predicate t -> assert false | Terms.Equation (l,r,ty,_) -> @@ -143,7 +169,7 @@ module Superposition (B : Terms.Blob) = (demod table vl) in match left_position with - | Some (newt, subst, varlist, id2, pos, dir) -> + | Some (newt, subst, varlist, id2, dir, pos) -> begin match build_clause bag (fun _ -> true) Terms.Demodulation newt subst varlist id id2 pos dir @@ -157,7 +183,7 @@ module Superposition (B : Terms.Blob) = (demod table vl) with | None -> None - | Some (newt, subst, varlist, id2, pos, dir) -> + | Some (newt, subst, varlist, id2, dir, pos) -> match build_clause bag (fun _ -> true) Terms.Demodulation newt subst varlist id id2 pos dir with @@ -165,6 +191,39 @@ module Superposition (B : Terms.Blob) = | Some x -> Some (x,true) ;; + let parallel_demod table vl bag t pos ctx id = + match demod table vl t with + | None -> (bag,t,id) + | Some (newside, subst, vl, id2, dir) -> + match build_clause bag (fun _ -> true) + Terms.Demodulation (ctx newside) subst vl id id2 pos dir + with + | None -> assert false + | Some (bag,(id,_,_,_)) -> + (bag,newside,id) + ;; + + let demodulate_once ~jump_to_right bag (id, literal, vl, pr) table = + match literal with + | Terms.Predicate t -> assert false + | Terms.Equation (l,r,ty,_) -> + let bag,l,id1 = if jump_to_right then (bag,l,id) else + parallel_positions bag [2] + (fun x -> Terms.Node [ Terms.Leaf B.eqP; ty; x; r ]) id l + (parallel_demod table vl) + in + let jump_to_right = id1 = id in + let bag,r,id2 = + parallel_positions bag [3] + (fun x -> Terms.Node [ Terms.Leaf B.eqP; ty; l; x ]) id1 r + (parallel_demod table vl) + in + if id = id2 then None + else + let cl,_,_ = Terms.get_from_bag id2 bag in + Some ((bag,cl),jump_to_right) + ;; + let rec demodulate ~jump_to_right bag clause table = match demodulate_once ~jump_to_right bag clause table with | None -> bag, clause @@ -172,8 +231,37 @@ module Superposition (B : Terms.Blob) = bag clause table ;; - let demodulate bag clause table = demodulate ~jump_to_right:false - bag clause table + let rec demodulate_old ~jump_to_right bag clause table = + match demodulate_once_old ~jump_to_right bag clause table with + | None -> bag, clause + | Some ((bag, clause),r) -> demodulate_old ~jump_to_right:r + bag clause table + ;; + + let are_alpha_eq cl1 cl2 = + let get_term (_,lit,_,_) = + match lit with + | Terms.Predicate _ -> assert false + | Terms.Equation (l,r,ty,_) -> + Terms.Node [Terms.Leaf B.eqP; ty; l ; r] + in + try ignore(Unif.alpha_eq (get_term cl1) (get_term cl2)) ; true + with FoUnif.UnificationFailure _ -> false + ;; + + let demodulate bag clause table = +(* let (bag1,c1), (_,c2) =*) + demodulate ~jump_to_right:false bag clause table +(* demodulate_old ~jump_to_right:false bag clause table*) +(* in + if are_alpha_eq c1 c2 then bag1,c1 + else begin + prerr_endline (Pp.pp_unit_clause c1); + prerr_endline (Pp.pp_unit_clause c2); + prerr_endline "Bag :"; + prerr_endline (Pp.pp_bag bag1); + assert false + end*) ;; (* move away *) @@ -303,28 +391,29 @@ module Superposition (B : Terms.Blob) = ;; let rec orphan_murder bag acc i = - match Terms.M.find i bag with - | (_,_,_,Terms.Exact _),discarded -> (discarded,acc) - | (_,_,_,Terms.Step (_,i1,i2,_,_,_)),true -> (true,acc) - | (_,_,_,Terms.Step (_,i1,i2,_,_,_)),false -> + match Terms.get_from_bag i bag with + | (_,_,_,Terms.Exact _),discarded,_ -> (discarded,acc) + | (_,_,_,Terms.Step (_,i1,i2,_,_,_)),true,_ -> (true,acc) + | (_,_,_,Terms.Step (_,i1,i2,_,_,_)),false,_ -> if (List.mem i acc) then (false,acc) else match orphan_murder bag acc i1 with | (true,acc) -> (true,acc) | (false,acc) -> let (res,acc) = orphan_murder bag acc i2 in if res then res,acc else res,i::acc -;; + ;; - let orphan_murder bag cl = + let orphan_murder bag actives cl = let (id,_,_,_) = cl in - let (res,_) = orphan_murder bag [] id in + let actives = List.map (fun (i,_,_,_) -> i) actives in + let (res,_) = orphan_murder bag actives id in if res then debug "Orphan murdered"; res -;; + ;; (* demodulate and check for subsumption *) let simplify table maxvar bag clause = if is_identity_clause ~unify:false clause then bag,None - (* else if orphan_murder bag clause then bag,None *) + (* else if orphan_murder bag actives clause then bag,None *) else let bag, clause = demodulate bag clause table in if is_identity_clause ~unify:false clause then bag,None else @@ -335,10 +424,16 @@ module Superposition (B : Terms.Blob) = let simplify table maxvar bag clause = match simplify table maxvar bag clause with - | bag, None -> let (id,_,_,_) = clause in - Terms.M.add id (clause,true) bag, None + | bag, None -> + let (id,_,_,_) = clause in + let (_,_,iter) = Terms.get_from_bag id bag in + Terms.replace_in_bag (clause,true,iter) bag, None | bag, Some clause -> bag, Some clause -;; + (*let (id,_,_,_) = clause in + if orphan_murder bag clause then + Terms.M.add id (clause,true) bag, Some clause + else bag, Some clause*) + ;; let one_pass_simplification new_clause (alist,atable) bag maxvar = match simplify atable maxvar bag new_clause with @@ -366,7 +461,8 @@ module Superposition (B : Terms.Blob) = (* Simplification of new_clause with : * * - actives and cl if new_clause is not cl * * - only actives otherwise *) - match simplify atable1 maxvar bag new_clause with + match + simplify atable1 maxvar bag new_clause with | bag,None -> bag,(Some cl, None) (* new_clause has been discarded *) | bag,Some clause -> (* Simplification of each active clause with clause * @@ -427,46 +523,36 @@ module Superposition (B : Terms.Blob) = keep_simplified_aux ~new_cl:true cl (alist,atable) bag [] ;; - let are_alpha_eq cl1 cl2 = - let get_term (_,lit,_,_) = - match lit with - | Terms.Predicate _ -> assert false - | Terms.Equation (l,r,ty,_) -> - Terms.Node [Terms.Leaf B.eqP; ty; l ; r] - in - try ignore(Unif.alpha_eq (get_term cl1) (get_term cl2)) ; true - with FoUnif.UnificationFailure _ -> false -;; - (* this is like simplify but raises Success *) - let simplify_goal maxvar table bag g_actives clause = - let bag, clause = demodulate bag clause table in + let simplify_goal ~no_demod maxvar table bag g_actives clause = + let bag, clause = + if no_demod then bag, clause else demodulate bag clause table + in + if List.exists (are_alpha_eq clause) g_actives then None else if (is_identity_clause ~unify:true clause) then raise (Success (bag, maxvar, clause)) - else let (id,lit,vl,_) = clause in - let l,r,ty = - match lit with - | Terms.Equation(l,r,ty,_) -> l,r,ty - | _ -> assert false - in - match deep_eq ~unify:true l r ty [] (fun x -> x) (fun x -> x) - table (Some(bag,maxvar,clause,Subst.id_subst)) with - | None -> - if List.exists (are_alpha_eq clause) g_actives then None - else Some (bag, clause) - | Some (bag,maxvar,cl,subst) -> - prerr_endline "Goal subsumed"; - raise (Success (bag,maxvar,cl)) - (* + if vl = [] then Some (bag,clause) + else + let l,r,ty = + match lit with + | Terms.Equation(l,r,ty,_) -> l,r,ty + | _ -> assert false + in + match deep_eq ~unify:true l r ty [] (fun x -> x) (fun x -> x) + table (Some(bag,maxvar,clause,Subst.id_subst)) with + | None -> Some (bag,clause) + | Some (bag,maxvar,cl,subst) -> + prerr_endline "Goal subsumed"; + raise (Success (bag,maxvar,cl)) +(* else match is_subsumed ~unify:true bag maxvar clause table with - | None -> - if List.exists (are_alpha_eq clause) g_actives then None - else Some (bag, clause) + | None -> Some (bag, clause) | Some ((bag,maxvar),c) -> prerr_endline "Goal subsumed"; - raise (Success (bag,maxvar,c))*) + raise (Success (bag,maxvar,c)) +*) ;; (* =================== inference ===================== *) @@ -494,8 +580,7 @@ module Superposition (B : Terms.Blob) = else ((*prerr_endline ("Filtering: " ^ Pp.pp_foterm side ^ " =(< || =)" ^ - Pp.pp_foterm newside ^ " coming from " ^ - Pp.pp_unit_clause uc );*)None) + Pp.pp_foterm newside);*)None) else Some (context newside, subst, varlist, id, pos, dir) with FoUnif.UnificationFailure _ -> None) @@ -567,7 +652,7 @@ module Superposition (B : Terms.Blob) = let fresh_current, maxvar = Utils.fresh_unit_clause maxvar current in (* We need to put fresh_current into the bag so that all * * variables clauses refer to are known. *) - let bag, fresh_current = Utils.add_to_bag bag fresh_current in + let bag, fresh_current = Terms.add_to_bag fresh_current bag in (* We superpose current with active clauses *) let bag, maxvar, additional_new_clauses = superposition_with_table bag maxvar fresh_current atable @@ -585,6 +670,8 @@ module Superposition (B : Terms.Blob) = let infer_left bag maxvar goal (_alist, atable) = (* We superpose the goal with active clauses *) + if (match goal with (_,_,[],_) -> true | _ -> false) then bag, maxvar, [] + else let bag, maxvar, new_goals = superposition_with_table bag maxvar goal atable in @@ -593,7 +680,7 @@ module Superposition (B : Terms.Blob) = let bag, new_goals = List.fold_left (fun (bag, acc) g -> - match simplify_goal maxvar atable bag [] g with + match simplify_goal ~no_demod:false maxvar atable bag [] g with | None -> assert false | Some (bag,g) -> bag,g::acc) (bag, []) new_goals