X-Git-Url: http://matita.cs.unibo.it/gitweb/?a=blobdiff_plain;f=helm%2Fsoftware%2Fcomponents%2Fng_paramodulation%2Fsuperposition.ml;h=6f1fb0f7f91a3e1395bf3dc71fa6a65cb39a3136;hb=dce1bca274f93a3bddcc0f6b04cbf126ccff42b0;hp=53d2958d1c2d1788fc2ff36ac843a9d2b864aafe;hpb=942ec766879070892420f6297b5c078c1582b78d;p=helm.git diff --git a/helm/software/components/ng_paramodulation/superposition.ml b/helm/software/components/ng_paramodulation/superposition.ml index 53d2958d1..6f1fb0f7f 100644 --- a/helm/software/components/ng_paramodulation/superposition.ml +++ b/helm/software/components/ng_paramodulation/superposition.ml @@ -20,9 +20,13 @@ module Superposition (B : Orderings.Blob) = module Utils = FoUtils.Utils(B) module Pp = Pp.Pp(B) - exception Success of B.t Terms.bag * int * B.t Terms.unit_clause + exception Success of + B.t Terms.bag + * int + * B.t Terms.unit_clause + * B.t Terms.substitution - (* let debug s = prerr_endline s;; *) + (* let debug s = prerr_endline (Lazy.force s);; *) let debug _ = ();; let enable = true;; @@ -206,13 +210,15 @@ module Superposition (B : Orderings.Blob) = prof_demod.HExtlib.profile (demod table varlist) x ;; - let mydemod table varlist subterm = + 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,_)) -> + (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) -> @@ -261,7 +267,8 @@ module Superposition (B : Orderings.Blob) = (bag,subst,newside,id) ;; - let rec demodulate ~jump_to_right bag (id, literal, vl, pr) table = + 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,_) -> @@ -274,44 +281,11 @@ module Superposition (B : Orderings.Blob) = visit bag [3] (fun x -> Terms.Node [ Terms.Leaf B.eqP; ty; l; x ]) id1 r (ctx_demod table vl) - in + 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 - | 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 parallel_demod table vl bag t pos ctx id = match demod table vl t with | None -> (bag,t,id) @@ -324,42 +298,6 @@ 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_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,_,_) = match lit with @@ -371,43 +309,27 @@ module Superposition (B : Orderings.Blob) = with FoUnif.UnificationFailure _ -> false ;; - let demodulate bag clause table = - 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 - prerr_endline (Pp.pp_unit_clause clause); - prerr_endline (Pp.pp_unit_clause c1); - prerr_endline (Pp.pp_unit_clause c2); - prerr_endline "Bag1 :"; - prerr_endline (Pp.pp_bag bag1); - prerr_endline "Bag2 :"; - prerr_endline (Pp.pp_bag bag2); - assert false - end - ;; *) - let prof_demodulate = HExtlib.profile ~enable "demodulate";; let demodulate bag clause x = prof_demodulate.HExtlib.profile (demodulate bag clause) x ;; (* move away *) - let is_identity_clause ~unify = function + let is_identity_clause = function | _, Terms.Equation (_,_,_,Terms.Eq), _, _ -> true - | _, Terms.Equation (l,r,_,_), vl, proof when unify -> - (try ignore(Unif.unification (* vl *) [] l r); true - with FoUnif.UnificationFailure _ -> false) | _, Terms.Equation (_,_,_,_), _, _ -> false | _, Terms.Predicate _, _, _ -> assert false ;; + let is_identity_goal = function + | _, Terms.Equation (_,_,_,Terms.Eq), _, _ -> Some [] + | _, Terms.Equation (l,r,_,_), vl, proof -> + (try Some (Unif.unification (* vl *) [] l r) + with FoUnif.UnificationFailure _ -> None) + | _, Terms.Equation (_,_,_,_), _, _ -> None + | _, Terms.Predicate _, _, _ -> assert false + ;; + let build_new_clause bag maxvar filter rule t subst id id2 pos dir = let maxvar, _vl, subst = Utils.relocate maxvar (Terms.vars_of_term (Subst.apply_subst subst t)) subst in @@ -430,7 +352,6 @@ module Superposition (B : Orderings.Blob) = in bag, maxvar, res ;; - let rewrite_eq ~unify l r ty vl table = let retrieve = if unify then IDX.DT.retrieve_unifiables @@ -554,7 +475,7 @@ 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 = @@ -562,11 +483,12 @@ module Superposition (B : Orderings.Blob) = ;; (* demodulate and check for subsumption *) - let simplify table maxvar bag clause = - if is_identity_clause ~unify:false clause then bag,None + let simplify table maxvar bag clause = + debug (lazy "simplify..."); + if is_identity_clause 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 + if is_identity_clause clause then bag,None else match is_subsumed ~unify:false bag maxvar clause table with | None -> bag, Some clause @@ -594,7 +516,7 @@ 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 -> @@ -602,7 +524,7 @@ 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)) @@ -615,7 +537,7 @@ 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 * @@ -626,7 +548,7 @@ 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 -> @@ -636,7 +558,7 @@ 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 @@ -678,7 +600,7 @@ 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) @@ -695,12 +617,15 @@ 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) - then raise (Success (bag, maxvar, clause)) - else + if List.exists (are_alpha_eq clause) g_actives then None + else match (is_identity_goal clause) with + | Some subst -> raise (Success (bag,maxvar,clause,subst)) + | None -> let (id,lit,vl,_) = clause in - if vl = [] then Some (bag,clause) + (* this optimization makes sense only if we demodulated, since in + that case the clause should have been turned into an identity *) + if (vl = [] && not(no_demod)) + then Some (bag,clause) else let l,r,ty = match lit with @@ -711,15 +636,15 @@ module Superposition (B : Orderings.Blob) = 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)) + debug (lazy "Goal subsumed"); + raise (Success (bag,maxvar,cl,subst)) (* - else match is_subsumed ~unify:true bag maxvar clause table with + match is_subsumed ~unify:true bag maxvar clause table with | None -> Some (bag, clause) | Some ((bag,maxvar),c) -> prerr_endline "Goal subsumed"; raise (Success (bag,maxvar,c)) -*) +*) ;; let prof_simplify_goal = HExtlib.profile ~enable "simplify_goal";; @@ -807,14 +732,14 @@ 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 @@ -825,13 +750,13 @@ 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. *) @@ -840,14 +765,14 @@ 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 ;; @@ -863,7 +788,7 @@ 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 @@ -873,7 +798,7 @@ 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 ;;