From 942ec766879070892420f6297b5c078c1582b78d Mon Sep 17 00:00:00 2001 From: Andrea Asperti Date: Wed, 29 Jul 2009 15:56:18 +0000 Subject: [PATCH] New demodulation (innermost, optimized to avoid reducing already normalized subterms). --- .../ng_paramodulation/superposition.ml | 138 ++++++++++++++++-- 1 file changed, 125 insertions(+), 13 deletions(-) diff --git a/helm/software/components/ng_paramodulation/superposition.ml b/helm/software/components/ng_paramodulation/superposition.ml index 994a141c9..53d2958d1 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 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 @@ -177,6 +206,80 @@ module Superposition (B : Orderings.Blob) = prof_demod.HExtlib.profile (demod table varlist) x ;; + 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,_)) -> + 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 ~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 = + 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 demodulate_once_old ~jump_to_right bag (id, literal, vl, pr) table = match literal with | Terms.Predicate t -> assert false @@ -242,19 +345,20 @@ module Superposition (B : Orderings.Blob) = Some ((bag,cl),jump_to_right) ;; - let rec demodulate ~jump_to_right bag clause table = + let rec demodulate_old ~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,_,_) = @@ -268,19 +372,27 @@ module Superposition (B : Orderings.Blob) = ;; 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 + demodulate ~jump_to_right:false bag clause table +;; +(* + let (bag1,c1), (bag2,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 + else + begin + prerr_endline (Pp.pp_unit_clause clause); prerr_endline (Pp.pp_unit_clause c1); prerr_endline (Pp.pp_unit_clause c2); - prerr_endline "Bag :"; + prerr_endline "Bag1 :"; prerr_endline (Pp.pp_bag bag1); + prerr_endline "Bag2 :"; + prerr_endline (Pp.pp_bag bag2); assert false - end*) - ;; + end + ;; *) + let prof_demodulate = HExtlib.profile ~enable "demodulate";; let demodulate bag clause x = prof_demodulate.HExtlib.profile (demodulate bag clause) x -- 2.39.2