X-Git-Url: http://matita.cs.unibo.it/gitweb/?a=blobdiff_plain;ds=sidebyside;f=helm%2Fsoftware%2Fcomponents%2Fng_paramodulation%2Fsuperposition.ml;h=6a2950b0e3da34514327d96f988bb0599e50d3c9;hb=946065280df015323ce624769fd0c4261f8b4209;hp=994a141c93f5d8215ac4f7e9930b6528aa1e6cfe;hpb=63741bdebe93f58cef3ea791ca634ef17237bd7f;p=helm.git diff --git a/helm/software/components/ng_paramodulation/superposition.ml b/helm/software/components/ng_paramodulation/superposition.ml index 994a141c9..6a2950b0e 100644 --- a/helm/software/components/ng_paramodulation/superposition.ml +++ b/helm/software/components/ng_paramodulation/superposition.ml @@ -22,8 +22,8 @@ module Superposition (B : Orderings.Blob) = exception Success of B.t Terms.bag * int * B.t Terms.unit_clause - let debug s = prerr_endline s;; - let debug _ = ();; + (* let debug s = prerr_endline (Lazy.force s);; *) + let debug _ = ();; let enable = true;; let rec list_first f = function @@ -95,11 +95,40 @@ module Superposition (B : Orderings.Blob) = (bag, [hd], List.tl l, id) l in bag, Terms.Node l, id - else bag,t,id1 + else bag,t,id1 + (* else aux bag pos ctx id1 t *) | _ -> assert false in aux bag pos ctx id t ;; + + let visit bag pos ctx id t f = + let rec aux bag pos ctx id subst = function + | Terms.Leaf _ as t -> + let bag,subst,t,id = f bag t pos ctx id + in assert (subst=[]); bag,t,id + | Terms.Var i as t -> + let t= Subst.apply_subst subst t in + bag,t,id + | Terms.Node (hd::l) -> + 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 subst t in + if post = [] then bag, pre@[newt], [], id + else bag, pre @ [newt], List.tl post, id) + (bag, [hd], List.map (Subst.apply_subst subst) (List.tl l), id) l + in + let bag,subst,t,id1 = f bag (Terms.Node l) pos ctx id + in + if id1 = id then (assert (subst=[]); bag,t,id) + else aux bag pos ctx id1 subst t + | _ -> assert false + in + aux bag pos ctx id [] t + ;; let build_clause bag filter rule t subst id id2 pos dir = let proof = Terms.Step(rule,id,id2,dir,pos,subst) in @@ -177,38 +206,82 @@ module Superposition (B : Orderings.Blob) = prof_demod.HExtlib.profile (demod table varlist) x ;; - let demodulate_once_old ~jump_to_right bag (id, literal, vl, pr) table = - match literal with + let mydemod table varlist subterm = + let cands = + prof_demod_r.HExtlib.profile + (IDX.DT.retrieve_generalizations table) subterm + in + list_first + (fun (dir, ((id,lit,vl,_) as c)) -> + debug (lazy("candidate: " + ^ Pp.pp_unit_clause c)); + match lit with + | Terms.Predicate _ -> assert false + | Terms.Equation (l,r,_,o) -> + let side, newside = if dir=Terms.Left2Right then l,r else r,l in + try + let subst = + prof_demod_u.HExtlib.profile + (Unif.unification (* (varlist@vl) *) varlist subterm) side + in + let iside = + prof_demod_s.HExtlib.profile + (Subst.apply_subst subst) side + in + let inewside = + prof_demod_s.HExtlib.profile + (Subst.apply_subst subst) newside + in + if o = Terms.Incomparable || o = Terms.Invertible then + let o = + prof_demod_o.HExtlib.profile + (Order.compare_terms inewside) iside in + (* Riazanov, pp. 45 (ii) *) + if o = Terms.Lt then + Some (newside, subst, id, dir) + else + ((*prerr_endline ("Filtering: " ^ + Pp.pp_foterm side ^ " =(< || =)" ^ + Pp.pp_foterm newside ^ " coming from " ^ + Pp.pp_unit_clause uc );*)None) + else + Some (newside, subst, id, dir) + with FoUnif.UnificationFailure _ -> None) + (IDX.ClauseSet.elements cands) + ;; + + let ctx_demod table vl bag t pos ctx id = + match mydemod table vl t with + | None -> (bag,[],t,id) + | Some (newside, subst, id2, dir) -> + let inewside = Subst.apply_subst subst newside in + match build_clause bag (fun _ -> true) + Terms.Demodulation (ctx inewside) subst id id2 pos dir + with + | None -> assert false + | Some (bag,(id,_,_,_)) -> + (bag,subst,newside,id) + ;; + + let rec demodulate bag (id, literal, vl, pr) table = + debug (lazy "demodulate..."); + match literal with | Terms.Predicate t -> assert false | Terms.Equation (l,r,ty,_) -> - let left_position = if jump_to_right then None else - first_position [2] - (fun x -> Terms.Node [ Terms.Leaf B.eqP; ty; x; r ]) l - (demod table vl) - in - match left_position with - | Some (newt, subst, id2, dir, pos) -> - begin - match build_clause bag (fun _ -> true) Terms.Demodulation - newt subst id id2 pos dir - with - | None -> assert false - | Some x -> Some (x,false) - end - | None -> - match first_position - [3] (fun x -> Terms.Node [ Terms.Leaf B.eqP; ty; l; x ]) r - (demod table vl) - with - | None -> None - | Some (newt, subst, id2, dir, pos) -> - match build_clause bag (fun _ -> true) - Terms.Demodulation newt subst id id2 pos dir - with - | None -> assert false - | Some x -> Some (x,true) + let bag,l,id1 = + visit bag [2] + (fun x -> Terms.Node [ Terms.Leaf B.eqP; ty; x; r ]) id l + (ctx_demod table vl) + in + let bag,_,id2 = + visit bag [3] + (fun x -> Terms.Node [ Terms.Leaf B.eqP; ty; l; x ]) id1 r + (ctx_demod table vl) + in + let cl,_,_ = Terms.get_from_bag id2 bag in + bag,cl ;; - + let parallel_demod table vl bag t pos ctx id = match demod table vl t with | None -> (bag,t,id) @@ -221,41 +294,6 @@ module Superposition (B : Orderings.Blob) = (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 - | Some ((bag, clause),r) -> demodulate ~jump_to_right:r - 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 @@ -267,20 +305,6 @@ module Superposition (B : Orderings.Blob) = 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*) - ;; let prof_demodulate = HExtlib.profile ~enable "demodulate";; let demodulate bag clause x = prof_demodulate.HExtlib.profile (demodulate bag clause) x @@ -442,7 +466,7 @@ module Superposition (B : Orderings.Blob) = let (id,_,_,_) = cl 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 + if res then debug (lazy "Orphan murdered"); res ;; let prof_orphan_murder = HExtlib.profile ~enable "orphan_murder";; let orphan_murder bag actives x = @@ -450,7 +474,8 @@ module Superposition (B : Orderings.Blob) = ;; (* demodulate and check for subsumption *) - let simplify table maxvar bag clause = + let simplify table maxvar bag clause = + debug (lazy "simplify..."); if is_identity_clause ~unify:false clause then bag,None (* else if orphan_murder bag actives clause then bag,None *) else let bag, clause = demodulate bag clause table in @@ -482,7 +507,7 @@ module Superposition (B : Orderings.Blob) = match simplify atable maxvar bag new_clause with | bag,None -> bag,None (* new_clause has been discarded *) | bag,(Some clause) -> - let ctable = IDX.index_unit_clause maxvar IDX.DT.empty clause in + let ctable = IDX.index_unit_clause IDX.DT.empty clause in let bag, alist, atable = List.fold_left (fun (bag, alist, atable) c -> @@ -490,7 +515,7 @@ module Superposition (B : Orderings.Blob) = |bag,None -> (bag,alist,atable) (* an active clause as been discarded *) |bag,Some c1 -> - bag, c :: alist, IDX.index_unit_clause maxvar atable c) + bag, c :: alist, IDX.index_unit_clause atable c) (bag,[],IDX.DT.empty) alist in bag, Some (clause, (alist,atable)) @@ -503,7 +528,7 @@ module Superposition (B : Orderings.Blob) = let simplification_step ~new_cl cl (alist,atable) bag maxvar new_clause = let atable1 = if new_cl then atable else - IDX.index_unit_clause maxvar atable cl + IDX.index_unit_clause atable cl in (* Simplification of new_clause with : * * - actives and cl if new_clause is not cl * @@ -514,7 +539,7 @@ module Superposition (B : Orderings.Blob) = | bag,Some clause -> (* Simplification of each active clause with clause * * which is the simplified form of new_clause *) - let ctable = IDX.index_unit_clause maxvar IDX.DT.empty clause in + let ctable = IDX.index_unit_clause IDX.DT.empty clause in let bag, newa, alist, atable = List.fold_left (fun (bag, newa, alist, atable) c -> @@ -524,7 +549,7 @@ module Superposition (B : Orderings.Blob) = |bag,Some c1 -> if (c1 == c) then bag, newa, c :: alist, - IDX.index_unit_clause maxvar atable c + IDX.index_unit_clause atable c else bag, c1 :: newa, alist, atable) (bag,[],[],IDX.DT.empty) alist @@ -566,7 +591,7 @@ module Superposition (B : Orderings.Blob) = | bag,(None, Some _) -> bag,None | bag,(Some cl1, Some (clause, (alist,atable), newa)) -> let alist,atable = - (clause::alist, IDX.index_unit_clause maxvar atable clause) + (clause::alist, IDX.index_unit_clause atable clause) in keep_simplified_aux ~new_cl:(cl!=cl1) cl1 (alist,atable) bag (newa@tl) @@ -583,8 +608,8 @@ module Superposition (B : Orderings.Blob) = 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) + 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 @@ -695,14 +720,14 @@ module Superposition (B : Orderings.Blob) = (* We demodulate actives clause with current until all * * active clauses are reduced w.r.t each other *) (* let bag, (alist,atable) = keep_simplified (alist,atable) bag [current] in *) - let ctable = IDX.index_unit_clause maxvar IDX.DT.empty current in + let ctable = IDX.index_unit_clause IDX.DT.empty current in (* let bag, (alist, atable) = let bag, alist = HExtlib.filter_map_acc (simplify ctable) bag alist in bag, (alist, List.fold_left IDX.index_unit_clause IDX.DT.empty alist) in*) - debug "Simplified active clauses with fact"; + debug (lazy "Simplified active clauses with fact"); (* We superpose active clauses with current *) let bag, maxvar, new_clauses = List.fold_left @@ -713,13 +738,13 @@ module Superposition (B : Orderings.Blob) = bag, maxvar, newc @ acc) (bag, maxvar, []) alist in - debug "First superpositions"; + debug (lazy "First superpositions"); (* We add current to active clauses so that it can be * * superposed with itself *) let alist, atable = - current :: alist, IDX.index_unit_clause maxvar atable current + current :: alist, IDX.index_unit_clause atable current in - debug "Indexed"; + debug (lazy "Indexed"); 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. *) @@ -728,14 +753,14 @@ module Superposition (B : Orderings.Blob) = let bag, maxvar, additional_new_clauses = superposition_with_table bag maxvar fresh_current atable in - debug "Another superposition"; + debug (lazy "Another superposition"); let new_clauses = new_clauses @ additional_new_clauses in - debug (lazy (Printf.sprintf "Demodulating %d clauses" - (List.length new_clauses))); + (* debug (lazy (Printf.sprintf "Demodulating %d clauses" + (List.length new_clauses))); *) let bag, new_clauses = HExtlib.filter_map_monad (simplify atable maxvar) bag new_clauses in - debug "Demodulated new clauses"; + debug (lazy "Demodulated new clauses"); bag, maxvar, (alist, atable), new_clauses ;; @@ -751,7 +776,7 @@ module Superposition (B : Orderings.Blob) = let bag, maxvar, new_goals = superposition_with_table bag maxvar goal atable in - debug "Superposed goal with active clauses"; + debug(lazy "Superposed goal with active clauses"); (* We simplify the new goals with active clauses *) let bag, new_goals = List.fold_left @@ -761,7 +786,7 @@ module Superposition (B : Orderings.Blob) = | Some (bag,g) -> bag,g::acc) (bag, []) new_goals in - debug "Simplified new goals with active clauses"; + debug (lazy "Simplified new goals with active clauses"); bag, maxvar, List.rev new_goals ;;