module Superposition (B : Orderings.Blob) =
struct
module IDX = Index.Index(B)
- module Unif = FoUnif.Founif(B)
+ module Unif = FoUnif.FoUnif(B)
module Subst = FoSubst
module Order = B
module Utils = FoUtils.Utils(B)
module Pp = Pp.Pp(B)
+ module Clauses = Clauses.Clauses(B)
exception Success of B.t Terms.bag * int * B.t Terms.clause
- let debug s = prerr_endline s;;
+ let debug s = prerr_endline (Lazy.force s);;
let debug _ = ();;
let enable = true;;
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
+ let parallel_positions bag pos ctx id lit t f =
+ let rec aux bag pos ctx id lit = function
+ | Terms.Leaf _ as t -> f bag t pos ctx id lit
+ | Terms.Var _ as t -> bag,t,id,lit
| Terms.Node (hd::l) as t->
- let bag,t,id1 = f bag t pos ctx id in
+ let bag,t,id1,lit = f bag t pos ctx id lit in
if id = id1 then
- let bag, l, _, id =
+ let bag, l, _, id, lit =
List.fold_left
- (fun (bag,pre,post,id) t ->
+ (fun (bag,pre,post,id,lit) 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, [hd], List.tl l, id) l
+ let bag,newt,id,lit = aux bag newpos newctx id lit t in
+ if post = [] then bag, pre@[newt], [], id,lit
+ else bag, pre @ [newt], List.tl post, id, lit)
+ (bag, [hd], List.tl l, id,lit) l
in
- bag, Terms.Node l, id
- else bag,t,id1
+ bag, Terms.Node l, id, lit
+ else bag,t,id1,lit
| _ -> assert false
in
- aux bag pos ctx id t
+ aux bag pos ctx id lit t
;;
- let build_clause bag filter rule t subst id id2 pos dir =
+ let build_clause ~fresh bag maxvar filter rule t subst id id2 pos dir clause_ctx =
let proof = Terms.Step(rule,id,id2,dir,pos,subst) in
let t = Subst.apply_subst subst t in
if filter subst then
Terms.Equation (l, r, ty, o)
| t -> Terms.Predicate t
in
- let bag, uc =
- Terms.add_to_bag (0, [], [literal,true], Terms.vars_of_term t, proof) bag
+ let nlit,plit = clause_ctx literal in
+ let cl = (0, nlit, plit, [], proof) in
+ let vl = Clauses.vars_of_clause cl in
+ let cl,maxvar =
+ if fresh then Clauses.fresh_clause ~subst maxvar (0, nlit, plit, vl, proof)
+ else (0,nlit,plit,vl,proof),maxvar
in
- Some (bag, uc)
+ let bag, cl =
+ Terms.add_to_bag cl bag
+ in
+ Some (bag, maxvar, cl, literal)
else
((*prerr_endline ("Filtering: " ^ Pp.pp_foterm t);*)None)
;;
let prof_build_clause = HExtlib.profile ~enable "build_clause";;
- let build_clause bag filter rule t subst id id2 pos x =
- prof_build_clause.HExtlib.profile (build_clause bag filter rule t subst id id2 pos) x
+ let build_clause ~fresh bag maxvar filter rule t subst id id2 pos x =
+ prof_build_clause.HExtlib.profile
+ (build_clause ~fresh bag maxvar filter rule t subst id id2 pos) x
;;
prof_demod.HExtlib.profile (demod table varlist) x
;;
- let parallel_demod table vl bag t pos ctx id =
+ let parallel_demod table vl clause_ctx bag t pos ctx id lit =
match demod table vl t with
- | None -> (bag,t,id)
+ | None -> (bag,t,id,lit)
| Some (newside, subst, id2, dir) ->
- match build_clause bag (fun _ -> true)
- Terms.Demodulation (ctx newside) subst id id2 pos dir
+ match build_clause ~fresh:false bag 0 (fun _ -> true)
+ Terms.Demodulation (ctx newside) subst id id2 pos dir clause_ctx
with
| None -> assert false
- | Some (bag,(id,_,_,_,_)) ->
- (bag,newside,id)
+ | Some (bag,_,(id,_,_,_,_),lit) ->
+ (bag,newside,id,lit)
;;
- let demodulate_once ~jump_to_right bag (id, nlit, plit, vl, pr) table =
- match nlit,plit with
- |[],[literal,_] ->
- (match literal with
+ let demodulate_once ~jump_to_right bag id literal vl table clause_ctx =
+ 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
+ | Terms.Equation (l,r,ty,_) as lit ->
+ let bag,l,id1,lit = if jump_to_right then (bag,l,id,lit) else
parallel_positions bag [2]
- (fun x -> Terms.Node [ Terms.Leaf B.eqP; ty; x; r ]) id l
- (parallel_demod table vl)
+ (fun x -> Terms.Node [ Terms.Leaf B.eqP; ty; x; r ]) id lit l
+ (parallel_demod table vl clause_ctx)
in
let jump_to_right = id1 = id in
- let bag,r,id2 =
+ let bag,r,id2,lit =
parallel_positions bag [3]
- (fun x -> Terms.Node [ Terms.Leaf B.eqP; ty; l; x ]) id1 r
- (parallel_demod table vl)
+ (fun x -> Terms.Node [ Terms.Leaf B.eqP; ty; l; x ]) id1 lit r
+ (parallel_demod table vl clause_ctx)
in
if id = id2 then None
else
- let cl,_,_ = Terms.get_from_bag id2 bag in
- Some ((bag,cl),jump_to_right))
- | _ -> assert false;
- ;;
-
- 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
+ Some ((bag,id2,lit),jump_to_right)
;;
- let are_alpha_eq cl1 cl2 =
- let get_term (_,nlit,plit,_,_) =
- match nlit,plit with
- | [], [Terms.Equation (l,r,ty,_),_] ->
- Terms.Node [Terms.Leaf B.eqP; ty; l ; r]
- | _ -> assert false
+ let rec demodulate bag (id,nlit,plit,vl,proof) table =
+ let rec demod_lit ~jump_to_right bag id lit clause_ctx =
+ match demodulate_once ~jump_to_right bag id lit vl table clause_ctx with
+ | None -> bag, id, lit
+ | Some ((bag, id, lit),jump) ->
+ demod_lit ~jump_to_right:jump bag id lit clause_ctx
+ in
+ (*let cmp_bag,cmp_cl = match nlit,plit with
+ |[],[lit,_] ->
+ let bag, id, lit = demod_lit ~jump_to_right:false bag id lit (fun l -> nlit, [l,true])
+ in
+ let cl,_,_ = Terms.get_from_bag id bag in
+ bag,cl
+ |[lit,_],[] ->
+ let bag, id, lit = demod_lit ~jump_to_right:false bag id lit (fun l -> [l,true],[])
+ in
+ let cl,_,_ = Terms.get_from_bag id bag in
+ bag,cl
+ |_ -> assert false
+ in*)
+ let nlit,_,bag,id = if nlit = [] then nlit,[],bag,id
+ else List.fold_left
+ (fun (pre,post,bag,id) (lit,sel) ->
+ let bag, id, lit =
+ demod_lit ~jump_to_right:false bag id lit (fun l -> pre@[l,sel]@post,plit)
+ in
+ if post=[] then pre@[(lit,sel)],[],bag,id
+ else pre@[(lit,sel)],List.tl post,bag,id)
+ ([],List.tl nlit, bag, id) nlit
+ in
+ let _,_,bag,id = if plit = [] then plit,[],bag,id
+ else List.fold_left
+ (fun (pre,post,bag,id) (lit,sel) ->
+ let bag, id, lit =
+ demod_lit ~jump_to_right:false bag id lit (fun l -> nlit,pre@[l,sel]@post)
+ in
+ if post=[] then pre@[(lit,sel)],[],bag,id
+ else pre@[(lit,sel)],List.tl post,bag,id)
+ ([],List.tl plit, bag, id) plit
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_clause c1);
- prerr_endline (Pp.pp_clause c2);
- prerr_endline "Bag :";
- prerr_endline (Pp.pp_bag bag1);
- assert false
- end*)
+ let cl,_,_ = Terms.get_from_bag id bag in
+ bag,cl
;;
+
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
| _, [], [Terms.Equation (_,_,_,Terms.Eq),_], _, _ -> true
- | _, [], [Terms.Equation (l,r,_,_),_], vl, proof when unify ->
+ | _, [], [Terms.Equation (l,r,_,_),_], vl, _ when unify ->
(try ignore(Unif.unification (* vl *) [] l r); true
with FoUnif.UnificationFailure _ -> false)
- | _, [], [Terms.Equation (_,_,_,_),_], _, _ -> false
- | _ -> assert false
+ | _ -> 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
- match build_clause bag filter rule t subst id id2 pos dir with
- | Some (bag, c) -> Some ((bag, maxvar), c)
- | None -> None
- ;;
- let prof_build_new_clause = HExtlib.profile ~enable "build_new_clause";;
- let build_new_clause bag maxvar filter rule t subst id id2 pos x =
- prof_build_new_clause.HExtlib.profile (build_new_clause bag maxvar filter
- rule t subst id id2 pos) x
- ;;
+ let is_goal_trivial = function
+ | _, [Terms.Equation (_,_,_,Terms.Eq),_], [], _, _ -> true
+ | _, [Terms.Equation (l,r,_,_),_], [], vl, _ ->
+ (try ignore(Unif.unification (* vl *) [] l r); true
+ with FoUnif.UnificationFailure _ -> false)
+ | _ -> false
- let fold_build_new_clause bag maxvar id rule filter res =
+ let fold_build_new_clause bag maxvar id rule filter res clause_ctx =
+ debug (lazy (string_of_int (List.length res)));
let (bag, maxvar), res =
HExtlib.filter_map_acc
(fun (bag, maxvar) (t,subst,id2,pos,dir) ->
- build_new_clause bag maxvar filter rule t subst id id2 pos dir)
+ match build_clause ~fresh:true bag maxvar filter
+ rule t subst id id2 pos dir clause_ctx with
+ | None -> None
+ | Some (bag,maxvar,res,_) -> Some ((bag,maxvar),res))
(bag, maxvar) res
in
bag, maxvar, res
let id, dir, l, r, vl =
match c with
| (d,_,_, (id,[],[Terms.Equation (l,r,ty,_),_],vl,_))-> id, d, l, r, vl
+ | (d,_,_, (id,[Terms.Equation (l,r,ty,_),_],[],vl,_))-> id, d, l, r, vl
|_ -> assert false
in
let reverse = (dir = Terms.Left2Right) = b in
let is_subsumed ~unify bag maxvar (id, nlit, plit, vl, _) table =
match nlit,plit with
+ | [Terms.Equation (l,r,ty,_) ,_],[]
| [],[Terms.Equation (l,r,ty,_) ,_]->
(match rewrite_eq ~unify l r ty vl table with
| None -> None
| Some (id2, dir, subst) ->
let id_t = Terms.Node [ Terms.Leaf B.eqP; ty; r; r ] in
- build_new_clause bag maxvar (fun _ -> true)
- Terms.Superposition id_t subst id id2 [2] dir)
- | _ -> assert false
+ build_clause ~fresh:true bag maxvar (fun _ -> true)
+ Terms.Superposition id_t subst id id2 [2] dir (fun l -> [],[l,true]))
+ | _ -> None (* TODO : implement subsumption for clauses *)
;;
let prof_is_subsumed = HExtlib.profile ~enable "is_subsumed";;
let is_subsumed ~unify bag maxvar c x =
let subst1 = Unif.unification (* vl *) [] l r in
let lit =
match nlit,plit with
- | [],[Terms.Equation (l,r,ty,o),_] ->
+ | [Terms.Equation (l,r,ty,o),_],[] ->
Terms.Equation (FoSubst.apply_subst subst1 l,
FoSubst.apply_subst subst1 r, ty, o)
| _ -> assert false
(Terms.Node[Terms.Leaf B.eqP;ty;contextl r;contextr r])
in
(match
- build_new_clause bag maxvar (fun _ -> true)
+ build_clause ~fresh:true bag maxvar (fun _ -> true)
Terms.Superposition id_t
- subst1 id id2 (pos@[2]) dir
+ subst1 id id2 (pos@[2]) dir (fun l -> [],[l,true])
with
- | Some ((bag, maxvar), c) ->
+ | Some (bag, maxvar, c, _) ->
Some(bag,maxvar,c,newsubst)
| None -> assert false)
| None ->
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 =
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 (Clauses.are_alpha_eq_cl clause) g_actives then None else
+ if (is_goal_trivial clause)
then raise (Success (bag, maxvar, clause))
else
let (id,nlit,plit,vl,_) = clause in
else
let l,r,ty =
match nlit,plit with
- | [],[Terms.Equation(l,r,ty,_),_] -> l,r,ty
+ | [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)
(* =================== inference ===================== *)
(* this is OK for both the sup_left and sup_right inference steps *)
- let superposition table varlist subterm pos context =
+ let superposition table varlist is_pos subterm pos context =
let cands = IDX.DT.retrieve_unifiables table subterm in
- HExtlib.filter_map
- (fun (dir, _, _, (id,nlit,plit,vl,_ (*as uc*))) ->
+ let res = HExtlib.filter_map
+ (fun (dir, is_cand_pos, _, (id,nlit,plit,vl,_ (*as uc*))) ->
match nlit,plit with
| [],[Terms.Equation (l,r,_,o),_] ->
(let side, newside = if dir=Terms.Left2Right then l,r else r,l in
+ debug (lazy (Pp.pp_foterm subterm));
+ debug (lazy (Pp.pp_foterm side));
try
let subst =
Unif.unification (* (varlist@vl)*) [] subterm side
if o <> Terms.Lt && o <> Terms.Eq then
Some (context newside, subst, id, pos, dir)
else
- ((*prerr_endline ("Filtering: " ^
- Pp.pp_foterm side ^ " =(< || =)" ^
- Pp.pp_foterm newside);*)None)
+ (debug (lazy "Filtering out..."); None)
else
Some (context newside, subst, id, pos, dir)
with FoUnif.UnificationFailure _ -> None)
| _ -> assert false)
(IDX.ClauseSet.elements cands)
+ in
+ debug (lazy (string_of_int (List.length (IDX.ClauseSet.elements cands)) ^ " candidates"));
+ debug (lazy (string_of_int (List.length res) ^ " results"));
+ res
;;
(* Superposes selected equation with equalities in table *)
- let superposition_with_table bag maxvar (id,nlit,plit,vl,_) table =
- match nlit,plit with
- | [],[Terms.Equation (l,r,ty,Terms.Lt),_] ->
+ let superposition_with_table bag maxvar id vl lit is_pos clause_ctx table =
+ match lit with
+ | Terms.Equation (l,r,ty,Terms.Lt) ->
fold_build_new_clause bag maxvar id Terms.Superposition
(fun _ -> true)
(all_positions [3]
(fun x -> Terms.Node [ Terms.Leaf B.eqP; ty; l; x ])
- r (superposition table vl))
- | [],[Terms.Equation (l,r,ty,Terms.Invertible),_]
- | [],[Terms.Equation (l,r,ty,Terms.Gt),_] ->
+ r (superposition table vl is_pos)) clause_ctx
+ | Terms.Equation (l,r,ty,Terms.Invertible)
+ | Terms.Equation (l,r,ty,Terms.Gt) ->
fold_build_new_clause bag maxvar id Terms.Superposition
(fun _ -> true)
(all_positions [2]
(fun x -> Terms.Node [ Terms.Leaf B.eqP; ty; x; r ])
- l (superposition table vl))
- | [],[Terms.Equation (l,r,ty,Terms.Incomparable),_] ->
+ l (superposition table vl is_pos)) clause_ctx
+ | Terms.Equation (l,r,ty,Terms.Incomparable) ->
let filtering avoid subst = (* Riazanov: p.33 condition (iv) *)
let l = Subst.apply_subst subst l in
let r = Subst.apply_subst subst r in
(filtering Terms.Gt)
(all_positions [3]
(fun x -> Terms.Node [ Terms.Leaf B.eqP; ty; l; x ])
- r (superposition table vl))
+ r (superposition table vl is_pos)) clause_ctx
in
let bag, maxvar, l_terms =
fold_build_new_clause bag maxvar id Terms.Superposition
(filtering Terms.Lt)
(all_positions [2]
(fun x -> Terms.Node [ Terms.Leaf B.eqP; ty; x; r ])
- l (superposition table vl))
+ l (superposition table vl is_pos)) clause_ctx
in
bag, maxvar, r_terms @ l_terms
| _ -> assert false
;;
+ let superpose_literal id vl table is_pos (bag,maxvar,pre,post,acc) (lit,sel) =
+ let clause_ctx =
+ if is_pos then fun l -> [],pre@[l,true]@post
+ else fun l -> pre@[l,true]@post,[]
+ in
+ let bag, maxvar, newc =
+ superposition_with_table bag maxvar id vl lit is_pos clause_ctx table
+ in
+ if post = [] then bag,maxvar,pre@[lit,sel],[],newc@acc
+ else bag,maxvar,pre@[lit,sel],List.tl post,newc@acc
+ ;;
+
+
(* the current equation is normal w.r.t. demodulation with atable
* (and is not the identity) *)
let infer_right bag maxvar current (alist,atable) =
in
bag, (alist, List.fold_left IDX.index_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
- (fun (bag, maxvar, acc) active ->
- let bag, maxvar, newc =
- superposition_with_table bag maxvar active ctable
+ (fun (bag, maxvar, acc) (id,nlit,plit,vl,_) ->
+ let bag, maxvar, _, _, acc =
+ if nlit = [] then bag,maxvar,[],[],acc
+ else List.fold_left
+ (superpose_literal id vl ctable false) (bag,maxvar,[],List.tl nlit,acc) nlit
in
- bag, maxvar, newc @ acc)
+ let bag, maxvar, _, _, acc =
+ if plit = [] then bag,maxvar,[],[],acc
+ else List.fold_left
+ (superpose_literal id vl ctable true) (bag,maxvar,[],List.tl plit,acc) plit
+ in
+ bag, maxvar, 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_clause atable current
in
- debug "Indexed";
- let fresh_current, maxvar = Utils.fresh_clause maxvar current in
+ debug (lazy "Indexed");
+ let fresh_current, maxvar = Clauses.fresh_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 = Terms.add_to_bag fresh_current bag in
+ let bag, (id,nlit,plit,vl,_) = 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
+ let bag, maxvar, _, _, new_clauses =
+ if nlit = [] then bag,maxvar,[],[],new_clauses
+ else List.fold_left
+ (superpose_literal id vl atable false) (bag,maxvar,[],List.tl nlit,new_clauses) nlit
in
- debug "Another superposition";
- let new_clauses = new_clauses @ additional_new_clauses in
+ let bag, maxvar, _, _, new_clauses =
+ if plit = [] then bag,maxvar,[],[],new_clauses
+ else List.fold_left
+ (superpose_literal id vl atable true) (bag,maxvar,[],List.tl plit,new_clauses) plit
+ in
+ debug (lazy "Another superposition");
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
;;
(* 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
+ let (id,nlit,vl) =
+ match goal with
+ | (id,nlit,[],vl,_) -> id,nlit,vl
+ | _ -> assert false
+ in
+ let bag, maxvar, _, _, new_goals =
+ List.fold_left (superpose_literal id vl atable false)
+ (bag,maxvar,[],List.tl nlit,[]) nlit
in
- debug "Superposed goal with active clauses";
+ debug (lazy (string_of_int (List.length new_goals) ^ " new goals"));
(* We simplify the new goals with active clauses *)
let bag, new_goals =
List.fold_left
| 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
;;
projects / helm.git / blobdiff