exception Success of B.t Terms.bag * int * B.t Terms.unit_clause
- let debug s =
- () (* prerr_endline s *)
- ;;
+ let debug s = prerr_endline s;;
+ let debug _ = ();;
let rec list_first f = function
| [] -> None
;;
(* move away *)
- let is_identity_clause = function
+ let is_identity_clause ~unify = function
| _, Terms.Equation (_,_,_,Terms.Eq), _, _ -> true
- | _, Terms.Equation (l,r,_,_), vl, proof ->
+ | _, 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 rec deep_eq ~unify l r ty pos contextl contextr table acc =
match acc with
| None -> None
- | Some(bag,maxvar,[],subst) -> assert false
- | Some(bag,maxvar,(id,_,vl,_)::clauses,subst) ->
+ | Some(bag,maxvar,(id,lit,vl,p),subst) ->
let l = Subst.apply_subst subst l in
let r = Subst.apply_subst subst r in
try
let subst1,vl1 = Unif.unification vl [] l r in
- Some(bag,maxvar,clauses,Subst.concat subst1 subst)
+ let lit =
+ match lit with Terms.Predicate _ -> assert false
+ | Terms.Equation (l,r,ty,o) ->
+ Terms.Equation (FoSubst.apply_subst subst1 l,
+ FoSubst.apply_subst subst1 r, ty, o)
+ in
+ Some(bag,maxvar,(id,lit,vl1,p),Subst.concat subst1 subst)
with FoUnif.UnificationFailure _ ->
match rewrite_eq ~unify l r ty vl table with
| Some (id2, dir, subst1) ->
+ let newsubst = Subst.concat subst1 subst in
let id_t =
- Terms.Node[Terms.Leaf B.eqP;ty;contextl r;contextr r] in
+ FoSubst.apply_subst newsubst
+ (Terms.Node[Terms.Leaf B.eqP;ty;contextl r;contextr r])
+ in
(match
build_new_clause bag maxvar (fun _ -> true)
- Terms.Superposition id_t subst1 [] id id2 (2::pos) dir
+ Terms.Superposition id_t
+ subst1 [] id id2 (pos@[2]) dir
with
| Some ((bag, maxvar), c) ->
- Some(bag,maxvar,c::clauses,Subst.concat subst1 subst)
+ Some(bag,maxvar,c,newsubst)
| None -> assert false)
| None ->
match l,r with
footail postl, footail postr))
(acc,[a],List.tl la,List.tl lb) la lb
in acc
- | Terms.Var _, _
- | _, Terms.Var _ -> assert false
| _,_ -> None
;;
+ let rec orphan_murder bag acc i =
+ match Terms.M.find i bag with
+ | (_,_,_,Terms.Exact _),discarded -> (discarded,acc)
+ | (_,_,_,Terms.Step (_,i1,i2,_,_,_)),true -> (true,acc)
+ | (_,_,_,Terms.Step (_,i1,i2,_,_,_)),false ->
+ if (List.mem i acc) then (false,acc)
+ else match orphan_murder bag acc i1 with
+ | (true,acc) -> (true,acc)
+ | (false,acc) ->
+ let (res,acc) = orphan_murder bag acc i2 in
+ if res then res,acc else res,i::acc
+ ;;
+
+ let orphan_murder bag actives cl =
+ 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
+ ;;
+
(* demodulate and check for subsumption *)
let simplify table maxvar bag clause =
- let bag, clause = demodulate bag clause table in
+ 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
if is_identity_clause ~unify:false clause then bag,None
else
match is_subsumed ~unify:false bag maxvar clause table with
| Some _ -> bag, None
;;
+ let simplify table maxvar bag clause =
+ match simplify table maxvar bag clause with
+ | bag, None -> let (id,_,_,_) = clause in
+ Terms.M.add id (clause,true) bag, None
+ | bag, Some clause -> bag, Some clause
+ (*let (id,_,_,_) = clause in
+ if orphan_murder bag clause then
+ Terms.M.add id (clause,true) bag, Some clause
+ else bag, Some clause*)
+ ;;
+
let one_pass_simplification new_clause (alist,atable) bag maxvar =
match simplify atable maxvar bag new_clause with
- | bag,None -> None (* new_clause has been discarded *)
+ | bag,None -> bag,None (* new_clause has been discarded *)
| bag,(Some 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 ->
+ (fun (bag, alist, atable) c ->
match simplify ctable maxvar bag c with
- |bag,None -> acc (* an active clause as been discarded *)
+ |bag,None -> (bag,alist,atable)
+ (* an active clause as been discarded *)
|bag,Some c1 ->
bag, c :: alist, IDX.index_unit_clause atable c)
(bag,[],IDX.DT.empty) alist
in
- Some (clause, bag, (alist,atable))
+ bag, Some (clause, (alist,atable))
;;
let simplification_step ~new_cl cl (alist,atable) bag maxvar new_clause =
(* Simplification of new_clause with : *
* - actives and cl if new_clause is not cl *
* - only actives otherwise *)
- match simplify atable1 maxvar bag new_clause with
- | bag,None -> (Some cl, None) (* new_clause has been discarded *)
+ match
+ simplify atable1 maxvar bag new_clause with
+ | bag,None -> bag,(Some cl, None) (* new_clause has been discarded *)
| bag,Some clause ->
(* Simplification of each active clause with clause *
* which is the simplified form of new_clause *)
let ctable = IDX.index_unit_clause IDX.DT.empty clause in
let bag, newa, alist, atable =
List.fold_left
- (fun (bag, newa, alist, atable as acc) c ->
+ (fun (bag, newa, alist, atable) c ->
match simplify ctable maxvar bag c with
- |bag,None -> acc (* an active clause as been discarded *)
+ |bag,None -> (bag, newa, alist, atable)
+ (* an active clause as been discarded *)
|bag,Some c1 ->
if (c1 == c) then
bag, newa, c :: alist,
(bag,[],[],IDX.DT.empty) alist
in
if new_cl then
- (Some cl, Some (clause, (alist,atable), newa, bag))
+ bag, (Some cl, Some (clause, (alist,atable), newa))
else
(* if new_clause is not cl, we simplify cl with clause *)
match simplify ctable maxvar bag cl with
| bag,None ->
(* cl has been discarded *)
- (None, Some (clause, (alist,atable), newa, bag))
+ bag,(None, Some (clause, (alist,atable), newa))
| bag,Some cl1 ->
- (Some cl1, Some (clause, (alist,atable), newa, bag))
+ bag,(Some cl1, Some (clause, (alist,atable), newa))
;;
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 maxvar cl with
- | (None, _) -> assert false
- | (Some _, None) -> None
- | (Some _, Some (clause, (alist,atable), newa, bag)) ->
+ | _,(None, _) -> assert false
+ | bag,(Some _, None) -> bag,None
+ | bag,(Some _, Some (clause, (alist,atable), newa)) ->
keep_simplified_aux ~new_cl:(cl!=clause) clause (alist,atable)
bag (newa@newc)
else
match newc with
- | [] -> Some (cl, bag, (alist,atable))
+ | [] -> bag, Some (cl, (alist,atable))
| hd::tl ->
match simplification_step ~new_cl cl
(alist,atable) bag maxvar hd with
- | (None,None) -> assert false
- | (Some _,None) ->
+ | _,(None,None) -> assert false
+ | bag,(Some _,None) ->
keep_simplified_aux ~new_cl cl (alist,atable) bag tl
- | (None, Some _) -> None
- | (Some cl1, Some (clause, (alist,atable), newa, bag)) ->
+ | bag,(None, Some _) -> bag,None
+ | bag,(Some cl1, Some (clause, (alist,atable), newa)) ->
let alist,atable =
(clause::alist, IDX.index_unit_clause atable clause)
in
;;
(* this is like simplify but raises Success *)
- let simplify_goal maxvar table bag g_actives clause =
- let bag, clause = demodulate bag clause table in
- if (is_identity_clause clause)
+ let simplify_goal ~no_demod maxvar table bag g_actives clause =
+ 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
let (id,lit,vl,_) = clause in
let l,r,ty =
| _ -> assert false
in
match deep_eq ~unify:true l r ty [] (fun x -> x) (fun x -> x)
- table (Some(bag,maxvar,[clause],Subst.id_subst)) with
- | None ->
- if List.exists (are_alpha_eq clause) g_actives then None
- else Some (bag, clause)
+ table (Some(bag,maxvar,clause,Subst.id_subst)) with
+ | None -> Some (bag,clause)
| Some (bag,maxvar,cl,subst) ->
- debug "Goal subsumed";
- raise (Success (bag,maxvar,List.hd cl))
-*)
+ prerr_endline "Goal subsumed";
+ raise (Success (bag,maxvar,cl))
+(*
else match is_subsumed ~unify:true bag maxvar clause table with
- | None ->
- if List.exists (are_alpha_eq clause) g_actives then None
- else Some (bag, clause)
+ | None -> Some (bag, clause)
| Some ((bag,maxvar),c) ->
- debug "Goal subsumed";
- raise (Success (bag,maxvar,c))
+ prerr_endline "Goal subsumed";
+ raise (Success (bag,maxvar,c))
+*)
;;
(* =================== inference ===================== *)
let bag, new_goals =
List.fold_left
(fun (bag, acc) g ->
- match simplify_goal maxvar atable bag [] g with
+ match simplify_goal ~no_demod:false maxvar atable bag [] g with
| None -> assert false
| Some (bag,g) -> bag,g::acc)
(bag, []) new_goals
projects / helm.git / blobdiff