| _ -> false
;;
- let is_subsumed ~unify (id, lit, vl, _) table =
+ let build_new_clause bag maxvar filter rule t subst vl id id2 pos dir =
+ let maxvar, vl, relocsubst = Utils.relocate maxvar vl in
+ let subst = Subst.concat relocsubst subst in
+ match build_clause bag filter rule t subst vl id id2 pos dir with
+ | Some (bag, c) -> Some ((bag, maxvar), c)
+ | None -> None
+ ;;
+
+
+ let fold_build_new_clause bag maxvar id rule filter res =
+ let (bag, maxvar), res =
+ HExtlib.filter_map_acc
+ (fun (bag, maxvar) (t,subst,vl,id2,pos,dir) ->
+ build_new_clause bag maxvar filter rule t subst vl id id2 pos dir)
+ (bag, maxvar) res
+ in
+ bag, maxvar, res
+ ;;
+
+ let is_subsumed ~unify bag maxvar (id, lit, vl, _) table =
match lit with
| Terms.Predicate _ -> assert false
| Terms.Equation (l,r,ty,_) ->
let lcands = retrieve table l in
let rcands = retrieve table r in
let f b c =
- let dir, l, r, vl =
+ let id, dir, l, r, vl =
match c with
- | (d, (_,Terms.Equation (l,r,ty,_),vl,_))-> d, l, r, vl
+ | (d, (id,Terms.Equation (l,r,ty,_),vl,_))-> id, d, l, r, vl
|_ -> assert false
in
- let l, r = if (dir = Terms.Left2Right) = b then l,r else r,l in
- Terms.Node [ Terms.Leaf B.eqP; ty; l; r ], vl
+ let reverse = (dir = Terms.Left2Right) = b in
+ let l, r, proof_rewrite_dir = if reverse then l,r,Terms.Left2Right
+ else r,l, Terms.Right2Left in
+ (id,proof_rewrite_dir,Terms.Node [ Terms.Leaf B.eqP; ty; l; r ], vl)
in
let cands1 = List.map (f true) (IDX.ClauseSet.elements lcands) in
let cands2 = List.map (f false) (IDX.ClauseSet.elements rcands) in
let t = Terms.Node [ Terms.Leaf B.eqP; ty; l; r ] in
let locked_vars = if unify then [] else vl in
- List.exists
- (fun (c, vl1) ->
- try ignore(Unif.unification (vl@vl1) locked_vars c t); true
- with FoUnif.UnificationFailure _ -> false)
- (cands1 @ cands2)
+ let rec aux = function
+ | [] -> None
+ | (id2,dir,c,vl1)::tl ->
+ try
+ let subst,vl1 = Unif.unification (vl@vl1) locked_vars c t in
+ 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
+ with FoUnif.UnificationFailure _ -> aux tl
+ in
+ aux (cands1 @ cands2)
;;
(* demodulate and check for subsumption *)
- let simplify table bag clause =
+ let simplify table maxvar bag clause =
let bag, clause = demodulate bag clause table in
if is_identity_clause clause then None
else
- if is_subsumed ~unify:false clause table then None
- else Some (bag, clause)
+ match is_subsumed ~unify:false bag maxvar clause table with
+ | None -> Some (bag, clause)
+ | Some _ -> None
;;
- let one_pass_simplification new_clause (alist,atable) bag =
- match simplify atable bag new_clause with
+ let one_pass_simplification new_clause (alist,atable) bag maxvar =
+ match simplify atable maxvar bag new_clause with
| None -> None (* new_clause has been discarded *)
| Some (bag, clause) ->
let ctable = IDX.index_unit_clause IDX.DT.empty clause in
let bag, alist, atable =
List.fold_left
(fun (bag, alist, atable as acc) c ->
- match simplify ctable bag c with
+ match simplify ctable maxvar bag c with
|None -> acc (* an active clause as been discarded *)
|Some (bag, c1) ->
bag, c :: alist, IDX.index_unit_clause atable c)
Some (clause, bag, (alist,atable))
;;
- let simplification_step ~new_cl cl (alist,atable) bag new_clause =
+ let simplification_step ~new_cl cl (alist,atable) bag maxvar new_clause =
let atable1 =
if new_cl then atable else
IDX.index_unit_clause atable cl
(* Simplification of new_clause with : *
* - actives and cl if new_clause is not cl *
* - only actives otherwise *)
- match simplify atable1 bag new_clause with
+ match simplify atable1 maxvar bag new_clause with
| None -> (Some cl, None) (* new_clause has been discarded *)
| Some (bag, clause) ->
(* Simplification of each active clause with clause *
let bag, newa, alist, atable =
List.fold_left
(fun (bag, newa, alist, atable as acc) c ->
- match simplify ctable bag c with
+ match simplify ctable maxvar bag c with
|None -> acc (* an active clause as been discarded *)
|Some (bag, c1) ->
if (c1 == c) then
(Some cl, Some (clause, (alist,atable), newa, bag))
else
(* if new_clause is not cl, we simplify cl with clause *)
- match simplify ctable bag cl with
+ match simplify ctable maxvar bag cl with
| None ->
(* cl has been discarded *)
(None, Some (clause, (alist,atable), newa, bag))
(Some cl1, Some (clause, (alist,atable), newa, bag))
;;
- let keep_simplified cl (alist,atable) bag =
+ let keep_simplified cl (alist,atable) bag maxvar =
let rec keep_simplified_aux ~new_cl cl (alist,atable) bag newc =
if new_cl then
- match simplification_step ~new_cl cl (alist,atable) bag cl with
+ match simplification_step ~new_cl cl (alist,atable) bag maxvar cl with
| (None, _) -> assert false
| (Some _, None) -> None
| (Some _, Some (clause, (alist,atable), newa, bag)) ->
| [] -> Some (cl, bag, (alist,atable))
| hd::tl ->
match simplification_step ~new_cl cl
- (alist,atable) bag hd with
+ (alist,atable) bag maxvar hd with
| (None,None) -> assert false
| (Some _,None) ->
keep_simplified_aux ~new_cl cl (alist,atable) bag tl
(* this is like simplify but raises Success *)
let simplify_goal maxvar table bag clause =
let bag, clause = demodulate bag clause table in
- if (is_identity_clause clause) || (is_subsumed ~unify:true clause table)
+ if (is_identity_clause clause)
then raise (Success (bag, maxvar, clause))
- else bag, clause
+ else match is_subsumed ~unify:true bag maxvar clause table with
+ | None -> bag, clause
+ | Some ((bag,maxvar),c) ->
+ debug "Goal subsumed";
+ raise (Success (bag,maxvar,c))
;;
(* =================== inference ===================== *)
(IDX.ClauseSet.elements cands)
;;
- let build_new_clause bag maxvar filter rule t subst vl id id2 pos dir =
- let maxvar, vl, relocsubst = Utils.relocate maxvar vl in
- let subst = Subst.concat relocsubst subst in
- match build_clause bag filter rule t subst vl id id2 pos dir with
- | Some (bag, c) -> Some ((bag, maxvar), c)
- | None -> None
- ;;
-
-
- let fold_build_new_clause bag maxvar id rule filter res =
- let (bag, maxvar), res =
- HExtlib.filter_map_acc
- (fun (bag, maxvar) (t,subst,vl,id2,pos,dir) ->
- build_new_clause bag maxvar filter rule t subst vl id id2 pos dir)
- (bag, maxvar) res
- in
- bag, maxvar, res
- ;;
-
(* Superposes selected equation with equalities in table *)
let superposition_with_table bag maxvar (id,selected,vl,_) table =
match selected with
(fun _ -> true)
(all_positions [3]
(fun x -> Terms.Node [ Terms.Leaf B.eqP; ty; l; x ])
- r (superposition table vl))
+ r (superposition table vl))
| Terms.Equation (l,r,ty,Terms.Gt) ->
fold_build_new_clause bag maxvar id Terms.Superposition
(fun _ -> true)
debug "Another superposition";
let new_clauses = new_clauses @ additional_new_clauses in
let bag, new_clauses =
- HExtlib.filter_map_acc (simplify atable) bag new_clauses
+ HExtlib.filter_map_acc (simplify atable maxvar) bag new_clauses
in
debug "Demodulated new clauses";
bag, maxvar, (alist, atable), new_clauses
;;
end
-
-
-
projects / helm.git / blobdiff