X-Git-Url: http://git.nguyen.vg/gitweb/?a=blobdiff_plain;f=ata.ml;h=bb38863bad0285e25b696f1dfe85528557bf2854;hb=22e128466565745a4e74f3b9823e7884ee5c6157;hp=c12be8a5df11acc424faf78ecaee7e67c3b819b9;hpb=d04661689691b4587cfc45a35e98604fcdc2b878;p=SXSI%2Fxpathcomp.git

diff --git a/ata.ml b/ata.ml
index c12be8a..bb38863 100644
--- a/ata.ml
+++ b/ata.ml
@@ -1,8 +1,30 @@
-(* Todo refactor and remove this alias *)
 INCLUDE "debug.ml"
-module Tree = Tree.Binary
+INCLUDE "utils.ml"
+
+type jump_kind = [ `TAG of Tag.t | `CONTAINS of string | `NOTHING ]
+let cpt_trans = ref 0
+let miss_trans = ref 0
+let cpt_eval = ref 0
+let miss_eval = ref 0
+
+let gen_id =
+  let id = ref (-1) in
+    fun () -> incr id;!id
+
+let h_union = Hashtbl.create 4097
+
+let pt_cup s1 s2 =
+  (* special case, since this is a union we want hash(s1,s2) = hash(s2,s1) *)
+  let x = Ptset.hash s1 
+  and y = Ptset.hash s2 in
+  let h = if x < y then HASHINT2(x,y) else HASHINT2(y,x) in
+    try
+      Hashtbl.find h_union h
+    with
+      | Not_found -> let s = Ptset.union s1 s2
+	in
+	  Hashtbl.add h_union h s;s
 
-let gen_id() = Oo.id (object end)
 module State = struct
 
   type t = int
@@ -13,47 +35,59 @@ let mk_state = State.mk
 
 type state = State.t
 
-type predicate = Ptset.t*Ptset.t -> Tree.t -> [ `True | `False | `Maybe ] 
 
+	
 type formula_expr = 
   | False | True
-    | Or of formula * formula 
-    | And of formula * formula 
-    | Atom of ([ `Left | `Right ]*bool*state*predicate option)
+  | Or of formula * formula 
+  | And of formula * formula 
+  | Atom of ([ `Left | `Right  | `LLeft | `RRight  ]*bool*state)
 and formula = { fid: int;
-		  pos : formula_expr;
-		  neg : formula;
-		  st : Ptset.t*Ptset.t;
+		fkey : int;
+		pos : formula_expr;
+		neg : formula;
+		st : (Ptset.t*Ptset.t*Ptset.t)*(Ptset.t*Ptset.t*Ptset.t);
+		size: int;
 	      }
     
+external hash_const_variant : [> ] -> int = "%identity" 
+external vb : bool -> int = "%identity"
+
+let hash_node_form t = match t with 
+  | False -> 0
+  | True -> 1
+  | And(f1,f2) -> (2+17*f1.fkey + 37*f2.fkey) (*land max_int *)
+  | Or(f1,f2) -> (3+101*f1.fkey + 253*f2.fkey) (*land max_int *)
+  | Atom(v,b,s) -> HASHINT3(hash_const_variant v,(3846*(vb b) +257),s)
+
+	
 
 module FormNode = 
 struct
   type t = formula
-  let hash = function
-    | False -> 0
-    | True -> 1
-    | And(f1,f2) -> 2+17*f1.fid + 37*f2.fid
-    | Or(f1,f2) -> 3+101*f1.fid + 253*f2.fid
-    | Atom(d,b,s,_) -> 5+(if d=`Left then 11 else 19)*(if b then 23 else 31)*s
-
-  let hash t = (hash t.pos) land max_int
-
+      
+  let hash t = t.fkey
   let equal f1 f2 = 
+    if f1.fid == f2.fid || f1.fkey == f2.fkey || f1.pos == f2.pos then true
+    else
     match f1.pos,f2.pos with
       | False,False | True,True -> true
-      | Atom(d1,b1,s1,_), Atom(d2,b2,s2,_) when (d1 = d2) && (b1=b2) &&(s1=s2) -> true
+      | Atom(d1,b1,s1), Atom(d2,b2,s2) when (b1==b2) &&  (s1==s2) && (d1 = d2) -> true
       | Or(g1,g2),Or(h1,h2) 
       | And(g1,g2),And(h1,h2)  -> g1.fid == h1.fid && g2.fid == h2.fid
       | _ -> false
+
 end
 module WH = Weak.Make(FormNode)
 
 let f_pool = WH.create 107
 
+let empty_triple = Ptset.empty,Ptset.empty,Ptset.empty
+let empty_hex = empty_triple,empty_triple
+
 let true_,false_ = 
-  let rec t = { fid = 1; pos = True; neg = f ; st = Ptset.empty,Ptset.empty}
-  and f = { fid = 0; pos = False; neg = t; st = Ptset.empty,Ptset.empty }
+  let rec t = { fid = 1; pos = True; fkey=1; neg = f ; st = empty_hex; size =1; }
+  and f = { fid = 0; pos = False; fkey=0; neg = t; st = empty_hex; size = 1; }
   in 
     WH.add f_pool f;
     WH.add f_pool t;
@@ -63,81 +97,114 @@ let is_true f = f.fid == 1
 let is_false f = f.fid == 0
 
 
-let cons pos neg s1 s2 = 
+let cons pos neg s1 s2 size1 size2 = 
   let rec pnode = 
     { fid = gen_id ();
+      fkey = hash_node_form pos;
       pos = pos;
       neg = nnode;
-      st = s1; }
+      st = s1; 
+      size = size1;}
   and nnode = { 
     fid = gen_id ();
     pos = neg;
+    fkey = hash_node_form neg;
     neg = pnode;
     st = s2;
+    size = size2;
   }
   in
     (WH.merge f_pool pnode),(WH.merge f_pool nnode)
 
-let atom_ ?(pred=None) d p s = 
+let atom_  d p s = 
   let si = Ptset.singleton s in
   let ss = match d with
-    | `Left -> si,Ptset.empty
-    | `Right -> Ptset.empty,si
-  in fst (cons (Atom(d,p,s,pred)) (Atom(d,not p,s,pred)) ss ss )
+    | `Left -> (si,Ptset.empty,si),empty_triple
+    | `Right -> empty_triple,(si,Ptset.empty,si)
+    | `LLeft -> (Ptset.empty,si,si),empty_triple
+    | `RRight -> empty_triple,(Ptset.empty,si,si)
+  in fst (cons (Atom(d,p,s)) (Atom(d,not p,s)) ss ss 1 1)
+       
+let union_hex  ((l1,ll1,lll1),(r1,rr1,rrr1))  ((l2,ll2,lll2),(r2,rr2,rrr2)) =
+  (pt_cup l1 l2 ,pt_cup ll1 ll2,pt_cup lll1 lll2),
+  (pt_cup r1 r2 ,pt_cup rr1 rr2,pt_cup rrr1 rrr2)
 
 let merge_states f1 f2 =
   let sp = 
-    Ptset.union (fst f1.st) (fst f2.st),
-    Ptset.union (snd f1.st) (snd f2.st)
+    union_hex f1.st f2.st
   and sn = 
-    Ptset.union (fst f1.neg.st) (fst f2.neg.st),
-    Ptset.union (snd f1.neg.st) (snd f2.neg.st)
+    union_hex f1.neg.st f2.neg.st
   in
     sp,sn
+      
+let full_or_ f1 f2 = 
+  let f1,f2 = if f1.fid < f2.fid then f2,f1 else f1,f2 in
+  let sp,sn = merge_states f1 f2 in
+  let psize = f1.size + f2.size in
+  let nsize = f1.neg.size + f2.neg.size in
+    fst (cons (Or(f1,f2)) (And(f1.neg,f2.neg)) sp sn psize nsize )
 
 let or_ f1 f2 = 
+  let f1,f2 = if f1.fid < f2.fid then f2,f1 else f1,f2 in
   if is_true f1 || is_true f2 then true_
   else if is_false f1 && is_false f2 then false_
   else if is_false f1 then f2
   else if is_false f2 then f1
   else 
+    let psize = f1.size + f2.size in
+    let nsize = f1.neg.size + f2.neg.size in
     let sp,sn = merge_states f1 f2 in
-      fst (cons (Or(f1,f2)) (And(f1.neg,f2.neg)) sp sn)
+      fst (cons (Or(f1,f2)) (And(f1.neg,f2.neg)) sp sn psize nsize)
 
 
 
 let and_ f1 f2 = 
+  let f1,f2 = if f1.fid < f2.fid then f2,f1 else f1,f2 in
   if is_true f1 && is_true f2 then true_
   else if is_false f1 || is_false f2 then false_
   else if is_true f1 then f2 
   else if is_true f2 then f1
   else
+    let psize = f1.size + f2.size in
+    let nsize = f1.neg.size + f2.neg.size in
     let sp,sn = merge_states f1 f2 in
-      fst (cons (And(f1,f2)) (Or(f1.neg,f2.neg)) sp sn)
+      fst (cons (And(f1,f2)) (Or(f1.neg,f2.neg)) sp sn psize nsize)
 	
 
 let not_ f = f.neg
 
-type property = [ `None | `Existential  ]
-let get_prop h s = 
-  try
-    Hashtbl.find h s 
-  with 
-      Not_found -> `None
-      
-type t = { 
+let k_hash (s,t) = HASHINT2(Ptset.hash s,Tag.hash t)
+
+module HTagSetKey =
+struct 
+  type t = Ptset.t*Tag.t 
+  let equal (s1,s2) (t1,t2) =  (s2 == t2) &&  Ptset.equal s1 t1
+  let hash = k_hash
+end
+
+module HTagSet = Hashtbl.Make(HTagSetKey)
+
+type skiplist = Nothing | All 
+		| Zero of skiplist 
+		| One of skiplist | Two of skiplist | Three of skiplist 
+		| Four of skiplist | Five of skiplist | Six of skiplist 
+		| Seven of skiplist | Eight of skiplist | Nine of skiplist		
+
+ 
+type formlist = Nil | Cons of state*formula*int*bool*formlist
+
+type 'a t = { 
     id : int;
-    states : Ptset.t;
+    mutable states : Ptset.t;
     init : Ptset.t;
-    final : Ptset.t;
+    mutable final : Ptset.t;
     universal : Ptset.t;
+    starstate : Ptset.t option;
     (* Transitions of the Alternating automaton *)
-    (* (tags,q) -> (marking,formula) *)
-    phi : ((TagSet.t*state),(bool*formula)) Hashtbl.t;
-    delta : (TagSet.t,(Ptset.t*bool*Ptset.t*Ptset.t)) Hashtbl.t;
-    properties : (state,property) Hashtbl.t;
-  }
-	   
+    phi : (state,(TagSet.t*(bool*formula*bool)) list) Hashtbl.t;
+    sigma : (int,('a t -> Tree.t -> Tree.t -> Ptset.t*'a)) Hashtbl.t;
+}
+
   module Pair (X : Set.OrderedType) (Y : Set.OrderedType) =
   struct
     type t = X.t*Y.t
@@ -150,7 +217,7 @@ type t = {
   module PL = Set.Make (Pair (Ptset) (Ptset))
 
 
-      let pr_st ppf l = Format.fprintf ppf "{";
+  let pr_st ppf l = Format.fprintf ppf "{";
     begin
       match l with
 	|	[] -> ()
@@ -161,7 +228,7 @@ type t = {
     Format.fprintf ppf " }"
   let rec pr_frm ppf f = match f.pos with
     | True -> Format.fprintf ppf "⊤"
-    | False -> Format.fprintf ppf "⊤"
+    | False -> Format.fprintf ppf "⊥"
     | And(f1,f2) -> 
 	Format.fprintf ppf "(";
 	(pr_frm ppf f1);
@@ -172,80 +239,13 @@ type t = {
 	(pr_frm ppf f1);
 	Format.fprintf ppf " ∨ ";
 	(pr_frm ppf f2);
-    | Atom(dir,b,s,p) -> Format.fprintf ppf "%s%s[%i]%s"
+    | Atom(dir,b,s) -> Format.fprintf ppf "%s%s[%i]"
 	(if b then "" else "¬")
-	(if dir = `Left then "↓₁" else "↓₂")s 
-	  (match p with None -> "" | _ -> " <hint>")
-
-  let dnf_hash = Hashtbl.create 17
-
-  let rec dnf_aux f = match f.pos with
-    | False -> PL.empty
-    | True -> PL.singleton (Ptset.empty,Ptset.empty)
-    | Atom(`Left,_,s,_) -> PL.singleton (Ptset.singleton s,Ptset.empty) 
-    | Atom(`Right,_,s,_) -> PL.singleton (Ptset.empty,Ptset.singleton s)
-    | Or(f1,f2) -> PL.union (dnf f1) (dnf f2)
-    | And(f1,f2) ->
-	  let pl1 = dnf f1
-	  and pl2 = dnf f2
-	  in
-	    PL.fold (fun (s1,s2) acc ->
-		       PL.fold ( fun (s1', s2') acc' ->
-				   (PL.add 
-				      ((Ptset.union s1 s1'),
-				       (Ptset.union s2 s2')) acc') )
-			  pl2 acc ) 
-	      pl1 PL.empty
-
-
-  and dnf f = 
-    try 
-      Hashtbl.find dnf_hash f.fid
-    with
-	Not_found -> 
-	  let d = dnf_aux f in
-	    Hashtbl.add dnf_hash f.fid d;d
-
-	      
-  let equal_form f1 f2 = 
-    (f1.fid == f2.fid) || (FormNode.equal f1 f2) || (PL.equal (dnf f1) (dnf f2))
-
-  let alt_trans_to_nfa ?(accu=[]) ts s mark f =
-    (* todo memoize *)
-    let f' = dnf f in
-      PL.fold (fun (s1,s2) acc -> (ts,s,mark,s1,s2)::acc) f' accu
-      
-
-  let possible_trans ?(accu=[]) a q tag =
-    (* todo change the data structure to avoid creating (,) *)
-    let ata_trans = 
-      Hashtbl.fold (fun (ts,s) (m,f) acc -> 		      
-		      if (q==s) && (TagSet.mem tag ts)
-		      then (ts,s,m,f)::acc
-		      else acc) a.phi []
-    in
-      if ata_trans != [] 
-      then begin	
-	List.iter (fun (ts,s,m,f) ->
-		     (* The following builds too many transitions in the nfa 
-		     let ts' = TagSet.remove tag ts
-		     in 
-		       Hashtbl.remove a.phi (ts,s);
-		       if not (TagSet.is_empty ts')
-		       then Hashtbl.add a.phi (ts',s) (m,f)
-		     *)
-		     Hashtbl.remove a.phi (ts,s)
-		  ) ata_trans;
-	(* let tstag = TagSet.tag tag in *)
-	let nfa_trs = List.fold_left (fun acc (ts,s,m,f) ->
-					alt_trans_to_nfa ~accu:acc ts s m f) [] ata_trans
-	in 
-	  List.iter (fun (ts,s,m,s1,s2) -> 
-		       Hashtbl.add a.delta ts ((Ptset.singleton s),m,s1,s2)) nfa_trs
-      end;
-      Hashtbl.fold (fun ts (s,m,s1,s2) acc -> 
-		      if (Ptset.mem q s) && (TagSet.mem tag ts)
-		      then  (m,s1,s2)::acc else acc) a.delta accu		     
+	(match  dir with 
+	   | `Left ->  "↓₁" 
+	   | `Right -> "↓₂"
+	   | `LLeft ->  "⇓₁" 
+	   | `RRight -> "⇓₂") s 	  
 
   let dump ppf a = 
     Format.fprintf ppf "Automaton (%i) :\n" a.id;
@@ -254,43 +254,57 @@ type t = {
     Format.fprintf ppf "\nFinal states : "; pr_st ppf (Ptset.elements a.final);
     Format.fprintf ppf "\nUniversal states : "; pr_st ppf (Ptset.elements a.universal);
     Format.fprintf ppf "\nAlternating transitions :\n------------------------------\n";
-    let l = Hashtbl.fold (fun k t acc -> (k,t)::acc) a.phi [] in
+    let l = Hashtbl.fold (fun k t acc -> 
+			    (List.map (fun (t,(m,f,p)) -> (t,k),(m,f,p)) t)@ acc) a.phi [] in
     let l = List.sort (fun ((tsx,x),_) ((tsy,y),_) -> if x-y == 0 then TagSet.compare tsx tsy else x-y) l in
-    List.iter (fun ((ts,q),(b,f)) ->
+    List.iter (fun ((ts,q),(b,f,_)) ->
 		    
 		    let s = 
-		      try
-			Tag.to_string (TagSet.choose ts)
-		      with
-			| _ -> "*" 
+		      if TagSet.is_finite ts 
+		      then "{" ^ (TagSet.fold (fun t a -> a ^ " '" ^ (Tag.to_string t)^"'") ts "") ^" }"
+		      else let cts = TagSet.neg ts in
+			if TagSet.is_empty cts then "*" else
+			  (TagSet.fold (fun t a -> a ^ " " ^ (Tag.to_string t)) cts "*\\{"
+			  )^ "}"
 		    in
 		      Format.fprintf ppf "(%s,%i) %s " s q (if b then "=>" else "->");
 		      pr_frm ppf f;
 		      Format.fprintf ppf "\n")l;
     
     Format.fprintf ppf "NFA transitions :\n------------------------------\n";
-    Hashtbl.iter (fun (ts) (q,b,s1,s2) ->
-		    
-		    let s = 
-		      try
-			Tag.to_string (TagSet.choose ts)
-		      with
-			| _ -> "*" 
+(*    HTagSet.iter (fun (qs,t) (disp,b,_,flist,_,_) ->
+		    let (ls,lls,_),(rs,rrs,_) = 
+		      List.fold_left (fun ((a1,b1,c1),(a2,b2,c2)) (_,f) ->
+					let (x1,y1,z1),(x2,y2,z2) = f.st in
+					  ((Ptset.union x1 a1),(Ptset.union y1 b1),(Ptset.union c1 z1)),
+					((Ptset.union x2 a2),(Ptset.union y2 b2),(Ptset.union c2 z2)))
+			((Ptset.empty,Ptset.empty,Ptset.empty),
+			 (Ptset.empty,Ptset.empty,Ptset.empty))
+			flist 
 		    in
-		      pr_st ppf (Ptset.elements q);		      
-		      Format.fprintf ppf ",%s  %s " s (if b then "=>" else "->");
-		      Format.fprintf ppf "(";
-		      pr_st ppf (Ptset.elements s1);
-		      Format.fprintf ppf ",";
-		      pr_st ppf (Ptset.elements s2);
-		      Format.fprintf ppf ")\n" ) a.delta;    
-    Format.fprintf ppf "=======================================\n"
+		      pr_st ppf (Ptset.elements qs);
+		      Format.fprintf ppf ",%s  %s " (Tag.to_string t) (if b then "=>" else "->");
+		      List.iter (fun (q,f) ->
+				   Format.fprintf ppf "\n%i," q;				  
+				   pr_frm ppf f)	   flist;
+		      Format.fprintf ppf "\nleft=";
+		      pr_st ppf (Ptset.elements ls);
+		      Format.fprintf ppf " , ";
+		      pr_st ppf (Ptset.elements lls);		       
+		      Format.fprintf ppf ", right=";
+		      pr_st ppf (Ptset.elements rs);
+		      Format.fprintf ppf ", ";
+		      pr_st ppf (Ptset.elements rrs);
+		      Format.fprintf ppf ", first=%s, next=%s\n\n" disp.flabel disp.nlabel;
+      ) a.sigma;    *)
+    Format.fprintf ppf "=======================================\n%!"
     
   module Transitions = struct
-    type t =  state*TagSet.t*bool*formula
+    type t = state*TagSet.t*bool*formula*bool
     let ( ?< ) x = x
-    let ( >< ) state label = state,label
-    let ( >=> ) (state,(label,mark)) form = (state,label,mark,form)
+    let ( >< ) state (l,b) = state,(l,b,false)
+    let ( ><@ ) state (l,b) = state,(l,b,true)
+    let ( >=> ) (state,(label,mark,pred)) form = (state,label,mark,form,pred)
     let ( +| ) f1 f2 = or_ f1 f2
     let ( *& ) f1 f2 = and_ f1 f2
     let ( ** ) d s = atom_ d true s
@@ -299,245 +313,710 @@ type t = {
   end
   type transition = Transitions.t
 
-  let equal_trans (q1,t1,m1,f1) (q2,t2,m2,f2) =
-    (q1 == q2) && (TagSet.equal t1 t2) && (m1 == m2) && (equal_form f1 f2)
-    
-  module TS : Set.S with type elt = Tree.t = Set.Make(Tree)  
-  let res =  ref TS.empty
+  let equal_trans (q1,t1,m1,f1,_) (q2,t2,m2,f2,_) =
+    (q1 == q2) && (TagSet.equal t1 t2) && (m1 == m2) (*&& (equal_form f1 f2) *)
+      
 
+  module HFEval = Hashtbl.Make(
+    struct
+      type t = int*Ptset.t*Ptset.t
+      let equal (a,b,c) (d,e,f) =
+	a==d && (Ptset.equal b e) && (Ptset.equal c f)
+      let hash (a,b,c) = 
+	HASHINT3(a,Ptset.hash b,Ptset.hash c)
+    end)
+    
 
-  module BottomUpNew = struct
     
-IFDEF DEBUG
-THEN
-    type trace = 
-      | TNil of Ptset.t*Ptset.t
-      | TNode of Ptset.t*Ptset.t*bool* (int*bool*formula) list
-		    
-    let traces = Hashtbl.create 17
-    let dump_trace t = 
-      let out = open_out "debug_trace.dot"
+    
+  let hfeval = HFEval.create 4097
+    let eval_form_bool f s1 s2 =      
+      let rec eval f = match f.pos with
+	  (* test some inlining *)
+	| True -> true,true,true
+	| False -> false,false,false
+	| _ ->
+	    try	  
+	      HFEval.find hfeval (f.fid,s1,s2) 
+	    with
+	      |	Not_found -> let r = 		  
+		  match f.pos with
+		    | Atom((`Left|`LLeft),b,q) ->
+			if b == (Ptset.mem q s1) 
+			then (true,true,false) 
+			else false,false,false
+		    | Atom(_,b,q) -> 
+			if b == (Ptset.mem q s2) 
+			then (true,false,true)
+			else false,false,false			
+		    | Or(f1,f2) ->	    
+			let b1,rl1,rr1 = eval f1 
+			in
+			  if b1 && rl1 && rr1 then (true,true,true)
+			  else
+			    let b2,rl2,rr2 = eval f2
+			    in
+			    let rl1,rr1 = if b1 then rl1,rr1 else false,false
+			    and rl2,rr2 = if b2 then rl2,rr2 else false,false
+			    in (b1 || b2, rl1||rl2,rr1||rr2)				 
+		    | And(f1,f2) -> 
+			let b1,rl1,rr1 = eval f1 in
+			  if b1 && rl1 && rr1 then (true,true,true)
+			  else if b1 
+			  then let b2,rl2,rr2 = eval f2 in
+			    if b2 then (true,rl1||rl2,rr1||rr2)
+			    else (false,false,false)
+			  else (false,false,false) 
+		    | _ -> assert false
+		in
+		  HFEval.add hfeval (f.fid,s1,s2) r;
+		  r
+      in eval f
+
+
+    let form_list_fold_left f acc fl =
+      let rec loop acc fl = 
+	match fl with
+	  | Nil -> acc
+	  | Cons(s,frm,h,m,fll) -> loop (f acc s frm h m) fll
       in
-      let outf = Format.formatter_of_out_channel out in      
-	
-      let rec aux t num =
-	if Tree.is_node t 
-	then
-	  match (try Hashtbl.find traces (Tree.id t) with Not_found -> TNil(Ptset.empty,Ptset.empty)) with
-	    | TNode(r,s,mark,trs) ->
-		let numl = aux (Tree.left t) num in
-		let numr = aux (Tree.right t) (numl+1) in
-		let mynum = numr + 1 in
-		  Format.fprintf outf "n%i [ label=\"<%s>\\nr=" mynum (Tag.to_string (Tree.tag t));
-		  pr_st outf (Ptset.elements r);
-		  Format.fprintf outf "\\ns=";
-		  pr_st outf (Ptset.elements s);
-		  List.iter (fun (q,m,f) ->
-			       Format.fprintf outf "\\n%i %s" q (if m then "⇨" else "→");
-			       pr_frm outf f ) trs;
-		  Format.fprintf outf "\", %s shape=box ];\n"
-		    (if mark then "color=cyan1, style=filled," else "");		
-		  let _ = Format.fprintf outf "n%i -> n%i;\n" mynum numl in
-		  let _ = Format.fprintf outf "n%i -> n%i;\n" mynum numr in
-		  mynum
-	    | TNil(r,s) -> Format.fprintf outf "n%i [ shape=box, label=\"Nil\\nr=" num;
-		pr_st outf (Ptset.elements r);
-		Format.fprintf outf "\\ns=";
-		pr_st outf (Ptset.elements s);
-		Format.fprintf outf "\"];\n";num
-	else
-	  match Hashtbl.find traces (-10) with
-	    | TNil(r,s) -> 
-		Format.fprintf outf "n%i [ shape=box, label=\"Nil\\nr=" num;
-		pr_st outf (Ptset.elements r);
-		Format.fprintf outf "\\ns=";
-		pr_st outf (Ptset.elements s);
-		Format.fprintf outf "\"];\n";
-		num
-	    | _ -> assert false
+	loop acc fl
+
+    let h_formlist = Hashtbl.create 4096
+    let rec eval_formlist ?(memo=true) s1 s2 fl = 
+      match fl with
+      | Nil -> Ptset.empty,false,false,false,false
+      | Cons(q,f,h,mark,fll) ->
+	  let k = (h,Ptset.hash s1,Ptset.hash s2,mark)
+	  in
+	    
+	    try 
+	      if memo then Hashtbl.find h_formlist k
+	      else (raise Not_found)
+	    with
+		Not_found -> 
+	    let s,b',b1',b2',amark = eval_formlist (~memo:memo) s1 s2 fll in
+	    let b,b1,b2 = eval_form_bool f s1 s2 in
+	    let r = if b then (Ptset.add q s, b, b1'||b1,b2'||b2,mark||amark)
+	    else s,b',b1',b2',amark
+	    in(*
+	      Format.fprintf Format.err_formatter "\nEvaluating formula (%i) %i %s" h q (if mark then "=>" else "->");
+	      pr_frm (Format.err_formatter) f;
+	      Format.fprintf Format.err_formatter " in context ";
+	      pr_st Format.err_formatter (Ptset.elements s1);
+	      Format.fprintf Format.err_formatter ", ";
+	      pr_st Format.err_formatter (Ptset.elements s2);
+	      Format.fprintf Format.err_formatter " result is %b\n%!" b; *)
+	      (Hashtbl.add h_formlist k r;r)
+
+      	      
+	      
+    let tags_of_state a q = Hashtbl.fold 
+      (fun p l acc -> 
+	 if p == q then
+	   List.fold_left 
+	     (fun acc (ts,(_,_,aux)) -> 
+		if aux then acc else
+		  TagSet.cup ts acc) acc l
+	 else acc) a.phi TagSet.empty
+    
+      
 
+    let tags a qs = 
+      let ts = Ptset.fold (fun q acc -> TagSet.cup acc (tags_of_state a q)) qs TagSet.empty
       in
-	Format.fprintf outf "digraph G {\n";
-	ignore(aux t 0);
-	Format.fprintf outf "}\n%!";
-	close_out out;
-	ignore(Sys.command "dot -Tsvg debug_trace.dot > debug_trace.svg")
-END
-
-
-
-    let hfeval = Hashtbl.create 17 
-    let miss = ref 0
-    let call = ref 0
-    let rec findlist s1 s2 = function 
-      | [] -> raise Not_found
-      | ((ss1,ss2),r)::_ when
-	  (not (Ptset.is_empty s1)) && (Ptset.subset s1 ss1) &&
-	    (not (Ptset.is_empty s2)) && (Ptset.subset s2 ss2) -> r
-      | _::r -> findlist s1 s2 r
-
-    let eval_form f s1 s2 res1 res2 =
+	if TagSet.is_finite ts 
+	then `Positive(TagSet.positive ts)
+	else `Negative(TagSet.negative ts)
+      	
+    let inter_text a b =
+      match b with
+	| `Positive s -> let r = Ptset.inter a s in (r,Ptset.mem Tag.pcdata r, true)
+	| `Negative s -> let r = Ptset.diff a s in (r, Ptset.mem Tag.pcdata r, false)
+
+    let mk_nil_ctx x _ = Tree.mk_nil x
+    let next_sibling_ctx x _ = Tree.next_sibling x 
+    let r_ignore _ x = x
       
-      let rec eval_aux f = match f.pos with
-	| Atom(`Left,b,q,_) -> if b == (Ptset.mem q s1) then (true,res1) else false,TS.empty
-	| Atom(`Right,b,q,_) -> if b == (Ptset.mem q s2) then (true,res2) else false,TS.empty
-	| True -> true,(TS.union res1 res2)
-	| False -> false,TS.empty
-	| Or(f1,f2) ->
-	    let b1,r1 = eval_aux f1 
-	    and b2,r2 = eval_aux f2
-	    in
-	    let r1 = if b1 then r1 else TS.empty
-	    and r2 = if b2 then r2 else TS.empty
-	    in (b1 || b2, TS.union r1 r2)
-	      
-	| And(f1,f2) -> 
-	    let b1,r1 = eval_aux f1 
-	    and b2,r2 = eval_aux f2
-	    in
-	      if b1 && b2 then (true, TS.union r1 r2)
-	      else (false,TS.empty)
+    let set_get_tag r t = r := (fun _ -> t)
+
+    module type ResultSet = 
+    sig
+      type t
+      val empty : t
+      val cons : Tree.t -> t -> t
+      val concat : t -> t -> t
+      val iter : (Tree.t -> unit) -> t -> unit
+      val fold : (Tree.t -> 'a -> 'a) -> t -> 'a -> 'a
+      val map : (Tree.t -> Tree.t) -> t -> t
+      val length : t -> int
+    end
+
+    module Integer : ResultSet =
+    struct
+      type t = int
+      let empty = 0
+      let cons _ x = x+1
+      let concat x y = x + y
+      let iter _ _ = failwith "iter not implemented"
+      let fold _ _ _ = failwith "fold not implemented"
+      let map _ _ = failwith "map not implemented"
+      let length x = x
+    end
+
+    module IdSet : ResultSet = 
+    struct
+      type node = Nil 
+		  | Cons of Tree.t * node 
+		  | Concat of node*node
+   
+      and t = { node : node;
+		length :  int }
+
+      let empty = { node = Nil; length = 0 }
+	
+      let cons e t = { node = Cons(e,t.node); length = t.length+1 }
+      let concat t1 t2 = { node = Concat(t1.node,t2.node); length = t1.length+t2.length }
+      let append e t = { node = Concat(t.node,Cons(e,Nil)); length = t.length+1 } 
+	
+      let fold f l acc = 
+	let rec loop acc t = match t with
+	  | Nil -> acc
+	  | Cons (e,t) -> loop (f e acc) t
+	  | Concat (t1,t2) -> loop (loop acc t1) t2
+	in
+	  loop acc l.node
+	    
+      let length l = l.length
+	
+	
+      let iter f l =
+	let rec loop = function
+	  | Nil -> ()
+	  | Cons (e,t) -> f e; loop t
+	  | Concat(t1,t2) -> loop t1;loop t2
+	in loop l.node
+
+      let map f l =
+	let rec loop = function 
+	  | Nil -> Nil
+	  | Cons(e,t) -> Cons(f e, loop t)
+	  | Concat(t1,t2) -> Concat(loop t1,loop t2)
+	in
+	  { l with node = loop l.node }
 
-      in incr call;eval_aux f
+	   
+    end
+
+    module Run (RS : ResultSet) =
+    struct
+      let fmt = Format.err_formatter
+      let pr x = Format.fprintf fmt x
+      module Formlist = 
+      struct
+	type t = formlist
+	let nil : t = Nil
+	let cons q f i m l = Cons(q,f,i,m,l)
+	let hash = function Nil -> 0 | Cons(_,_,i,_,_) -> max_int land i
+	let pr fmt l = 
+	  let rec loop = function
+	    | Nil -> ()
+	    | Cons(q,f,_,m,l) ->
+		Format.fprintf fmt "%i %s" q (if m then "=>" else "->");
+		pr_frm fmt f;
+		Format.fprintf fmt "\n%!";
+		loop l
+	  in
+	    loop l
+      end
 	
+      type ptset_list = Nil | Cons of Ptset.t*int*ptset_list
+      let hpl l = match l with
+	| Nil -> 0
+	| Cons (_,i,_) -> i 
 
-    (* If true, then the formule may evaluate to true in the future,
-       if false it will always return false, i.e. necessary conditions are not
-       satisfied
-    *)
-
-    let val3 = function true -> `True
-      | false -> `False
-
-    let or3 a b = match a,b with
-      | `True,_ | _,`True -> `True
-      | `False,`False -> `False
-      | _ -> `Maybe
-
-    let and3 a b = match a,b with
-      | `True,`True -> `True
-      | `False,_ | _,`False -> `False
-      | _ -> `Maybe
-    let not3 = function 
-      | `True -> `False
-      | `False -> `True
-      | `Maybe -> `Maybe
-
-    let true3 = function true -> `Maybe
-      | false -> `False
-
-    let may_eval (s1,s2) f t = 
-      let rec aux f = match f.pos with 
-	| True -> `True
-	| False -> `False
-	| Or(f1,f2) -> or3 (aux f1) (aux f2)
-	| And(f1,f2) -> and3 (aux f1) (aux f2)
-	| Atom(dir,b,q,predo) ->
-	    and3 (true3 ((Ptset.mem q (match dir with
-					| `Left -> s1
-					| `Right -> s2)) == b))
-	      (match predo with
-		 | Some pred -> (pred (s1,s2) t)
-		 | None -> `True)
-	    
-      in aux f
-
-    let rec accepting_among a t r =
-      let r = Ptset.diff r a.final in
-      let rest = Ptset.inter a.final r in
-	if Ptset.is_empty r then r,TS.empty else 
-	  if (not (Tree.is_node t)) 
-	  then 
-	    let _ = D(Hashtbl.add traces (-10) (TNil(r,Ptset.inter a.final r)))
-	    in
-	      Ptset.inter a.final r,TS.empty
-	  else 
-	    let tag = Tree.tag t
-	    and t1 = Tree.first_child t
-	    and t2 = Tree.next_sibling t
-	    in
-	    let r1,r2,trs =
-	      Hashtbl.fold (fun (ts,q) ((m,f)as tr) ((ar1,ar2,lt)as acc) ->
-			      if (TagSet.mem tag ts) && Ptset.mem q r 
-			      then begin
-				(* Format.fprintf Format.err_formatter "Tree with tag %s qualifies for transition : (%s,%i)%s"
-				   (Tag.to_string tag)
-				   (try
-				   Tag.to_string (TagSet.choose ts)
-				   with
-				  | _ -> "*" )
-				   q
-				   (if m then "=>" else "->");
-				   pr_frm Format.err_formatter f;
-				   Format.fprintf Format.err_formatter "\n"; *)
-				let ls,rs = f.st in
-			      Ptset.union ls ar1,Ptset.union rs ar2,(q,tr)::lt
-			      end
-			      else acc
-			   ) a.phi (Ptset.empty,Ptset.empty,[])
-	    in
-	    let rtrue,rfalse,rmay,trs,selnodes = 
-	      List.fold_left (fun (at,af,am,atrs,selnodes) (q,(m,f)) -> 
-				let ppf = Format.err_formatter in
-				  match (*may_eval (r1,r2) f t *) `Maybe with
-			      | `True -> 
-				  (* Format.fprintf ppf "Will skip (%i) %s " q (if m then "=>" else "->");
-				  pr_frm ppf f;
-				  Format.fprintf ppf ", always true \n"; *)
-				  (Ptset.add q at),af,am,atrs,TS.add t selnodes
-			      | `False -> 
-				  (*Format.fprintf ppf "Will skip (%i) %s " q (if m then "=>" else "->");
-				  pr_frm ppf f;
-				  Format.fprintf ppf ", always false \n"; *)
-				  at,(Ptset.add q af),am,atrs,selnodes
-
-			      | `Maybe -> 
-(*				  Format.fprintf ppf "Must take (%i) %s " q (if m then "=>" else "->");
-				  pr_frm ppf f;
-				  Format.fprintf ppf "\n"; *)
-				  at,af,(Ptset.add q am),(q,(m,f))::atrs,selnodes)
-	    (Ptset.empty,Ptset.empty,Ptset.empty,[],TS.empty) trs
+      let cons s l = Cons (s,(Ptset.hash s) + 65599 * (hpl l), l)
+	  
+      let rec empty_size n = 
+	if n == 0 then Nil
+	else cons Ptset.empty (empty_size (n-1))
+	
+      let fold_pl f l acc = 
+	let rec loop l acc = match l with
+	    Nil -> acc
+	  | Cons(s,h,pl) -> loop pl (f s h acc)
 	in
-	let rr1,rr2,trs = 
-	  List.fold_left (fun ((ar1,ar2,trs)as acc) ((q,(_,f)as tr)) ->
-			    if Ptset.mem q rmay
-			    then let ls,rs = f.st in
-			      Ptset.union ls ar1,Ptset.union rs ar2,tr::trs
-			    else acc) (Ptset.empty,Ptset.empty,[]) trs
+	  loop l acc
+      let map_pl f l = 
+	let rec loop =
+	  function Nil -> Nil 
+	    | Cons(s,h,ll) -> cons (f s) (loop ll) 
+	in loop l
+      let iter_pl f l = 
+	let rec loop =
+	  function Nil -> ()
+	    | Cons(s,h,ll) ->  (f s);(loop ll) 
+	in loop l
+
+      let rev_pl l = 
+	let rec loop acc l = match l with 
+	  | Nil -> acc
+	  | Cons(s,_,ll) -> loop (cons s acc) ll
 	in
-	let s1,res1 = accepting_among a t1 rr1 
-	and s2,res2 = accepting_among a t2 rr2
+	  loop Nil l
+
+      let rev_map_pl f l  = 
+	let rec loop acc l = 
+	  match l with 
+	    | Nil -> acc
+	    | Cons(s,_,ll) -> loop (cons (f s) acc) ll
 	in
-	let res,set,mark,trs =  List.fold_left (fun  ((sel_nodes,res,amark,acctr) as acc) (q,(mark,f)) ->
-			    let b,resnodes = eval_form f s1 s2 res1 res2 in
-			      (*     if b then begin 
-				     pr_st Format.err_formatter (Ptset.elements s1);
-				     Format.fprintf Format.err_formatter ",";
-				     pr_st Format.err_formatter (Ptset.elements s2);
-				     Format.fprintf Format.err_formatter "  satisfies ";
-				     pr_frm Format.err_formatter f;
-				     Format.fprintf Format.err_formatter " for input tree %s\n" (Tag.to_string tag);
-				     end; *)
-			      if b 
-			      then 
-				(TS.union
-				   (if mark then TS.add t resnodes else resnodes)
-				   sel_nodes)
-				  ,Ptset.add q res,amark||mark,(q,mark,f)::acctr
-			      else acc
-			 ) (TS.empty,rtrue,false,[]) trs
-	in 
-	  
-	let set = Ptset.union a.final set in
-	let _ = D(Hashtbl.add traces (Tree.id t) (TNode(r,set,mark,trs))) in
-	  set,res	
+	  loop Nil l
+
+      let td_trans = Hashtbl.create 4096 
+
 	
-	    
-    let run a t = 
-      let st,res = accepting_among a t a.init in
-      let b = Ptset.is_empty (st) in
-      let _ = D(dump_trace t) in
-	if b then []
-	else (TS.elements res)
+      let choose_jump tagset qtags1 qtagsn a f_nil f_text f_t1 f_s1 f_tn f_sn f_notext =
+	let tags1,hastext1,fin1 = inter_text tagset (tags a qtags1) in
+	let tagsn,hastextn,finn = inter_text tagset (tags a qtagsn) in
+(*	  Format.fprintf Format.err_formatter "Tags below states ";
+	  pr_st Format.err_formatter (Ptset.elements qtags1);
+	  Format.fprintf Format.err_formatter " are { ";
+	  Ptset.iter (fun t -> Format.fprintf Format.err_formatter "%s " (Tag.to_string t)) tags1;
+	  Format.fprintf Format.err_formatter "}, %b,%b\n%!" hastext1 fin1;
+
+	  Format.fprintf Format.err_formatter "Tags below states ";
+	  pr_st Format.err_formatter (Ptset.elements qtagsn);
+	  Format.fprintf Format.err_formatter " are { ";
+	  Ptset.iter (fun t -> Format.fprintf Format.err_formatter "%s " (Tag.to_string t)) tagsn;
+	  Format.fprintf Format.err_formatter "}, %b,%b\n%!" hastextn finn;
+*)
+	  if (hastext1||hastextn) then f_text  (* jumping to text nodes doesn't work really well *)
+	  else if (Ptset.is_empty tags1) && (Ptset.is_empty tagsn) then f_nil
+	  else if (Ptset.is_empty tagsn) then 
+	    if (Ptset.is_singleton tags1) then f_t1 (Ptset.choose tags1)  (* TaggedChild/Sibling *)
+	    else f_s1 tags1 (* SelectChild/Sibling *)
+	  else if (Ptset.is_empty tags1) then 
+	    if (Ptset.is_singleton tagsn) then f_tn (Ptset.choose tagsn) (* TaggedDesc/Following *)
+	    else f_sn tagsn (* SelectDesc/Following *)
+	  else f_notext
 	  
-  end
+      let choose_jump_down a b c d =
+	choose_jump a b c d
+	  (Tree.mk_nil)
+	  (Tree.text_below)
+	  (*fun x -> let i,j = Tree.doc_ids x in
+	   let res = Tree.text_below x in
+	     Printf.printf "Calling text_below %s (tag=%s), docids= (%i,%i), res=%s\n"
+	       (Tree.dump_node x) (Tag.to_string (Tree.tag x)) i j (Tree.dump_node res);
+	     res*) 
+	  (fun _ -> Tree.node_child ) (* !! no tagged_child in Tree.ml *)
+	  (fun _ -> Tree.node_child ) (* !! no select_child in Tree.ml *)
+	  (Tree.tagged_desc)
+	  (fun _ -> Tree.node_child ) (* !! no select_desc *)
+	  (Tree.node_child)
+
+      let choose_jump_next a b c d = 
+	choose_jump a b c d
+	  (fun t _ -> Tree.mk_nil t)
+	  (Tree.text_next)
+	  (*fun x y -> let i,j = Tree.doc_ids x in
+	   let res = Tree.text_next x y in
+	     Printf.printf "Calling text_next %s (tag=%s) ctx=%s, docids= (%i,%i), res=%s\n"
+	       (Tree.dump_node x) (Tag.to_string (Tree.tag x)) (Tree.dump_node y) i j (Tree.dump_node res);
+	     res*) 
+	  
+	  (fun _ -> Tree.node_sibling_ctx) (* !! no tagged_sibling in Tree.ml *)
+	  (fun _ -> Tree.node_sibling_ctx) (* !! no select_child in Tree.ml *)
+	  (Tree.tagged_foll_below)
+	  (fun _ -> Tree.node_sibling_ctx) (* !! no select_foll *)
+	  (Tree.node_sibling_ctx)
+	  
+				    
+      let get_trans slist tag a t = 
+	try 
+	  Hashtbl.find td_trans (tag,hpl slist)
+	with
+	  | Not_found -> 
+	      let fl_list,llist,rlist,ca,da,sa,fa = 
+		fold_pl 
+		  (fun set _ (fll_acc,lllacc,rllacc,ca,da,sa,fa) -> (* For each set *)
+		     let fl,ll,rr,ca,da,sa,fa = 
+		       Ptset.fold
+	 		 (fun q acc ->
+			    fst (
+	 		      List.fold_left 
+				(fun (((fl_acc,ll_acc,rl_acc,c_acc,d_acc,s_acc,f_acc),h_acc) as acc) 
+				   (ts,(m,f,_))  ->
+				     if (TagSet.mem tag ts)
+				     then 
+				       let (child,desc,below),(sibl,foll,after) = f.st in
+				       let h_acc = HASHINT3(h_acc,f.fid,HASHINT2(q,vb m)) in
+					 ((Formlist.cons q f h_acc m fl_acc,
+					   Ptset.union ll_acc below,
+					   Ptset.union rl_acc after,
+					   Ptset.union child c_acc,
+					   Ptset.union desc d_acc,
+					   Ptset.union sibl s_acc,
+					   Ptset.union foll f_acc),
+					  h_acc)				 
+				   else acc ) (acc,0) (
+				  try Hashtbl.find a.phi q 
+				  with
+				      Not_found -> Printf.eprintf "Looking for state %i, doesn't exist!!!\n%!"
+					q;[]
+				))
+			      
+			 ) set (Formlist.nil,Ptset.empty,Ptset.empty,ca,da,sa,fa)
+		     in fl::fll_acc, cons ll lllacc, cons rr rllacc,ca,da,sa,fa)
+		  slist ([],Nil,Nil,Ptset.empty,Ptset.empty,Ptset.empty,Ptset.empty)
+	      in
+		(* Logic to chose the first and next function *)
+	      let tags_below,tags_after = Tree.tags t tag in
+	      let first = choose_jump_down tags_below ca da a
+	      and next = choose_jump_next tags_after sa fa a in	
+	      let v = (fl_list,llist,rlist,first,next) in
+		Hashtbl.add td_trans (tag, hpl slist) v; v
+		  
+      let merge rb rb1 rb2 mark t res1 res2 = 
+	if rb 
+	then 
+	  let res1 = if rb1 then res1 else RS.empty
+	  and res2 = if rb2 then res2 else RS.empty
+	  in
+	    if mark then RS.cons t (RS.concat res1 res2)
+	    else RS.concat res1 res2
+	else RS.empty 
+	  
+      let top_down ?(noright=false) a t slist ctx slot_size =	
+	let pempty = empty_size slot_size in	
+	let eval_fold2_slist fll sl1 sl2 res1 res2 t =
+	  let res = Array.copy res1 in
+	  let rec fold l1 l2 fll i aq = match l1,l2,fll with
+	    | Cons(s1,_,ll1), Cons(s2, _ ,ll2),fl::fll -> 
+		let r',rb,rb1,rb2,mark = eval_formlist s1 s2 fl in
+(*		let _ = pr "Evaluation context : "; pr_st fmt (Ptset.elements s1);
+		  pr_st fmt (Ptset.elements s2);
+		  pr "Formlist (%i) : " (Formlist.hash fl);
+		  Formlist.pr fmt fl;
+		  pr "Results : "; pr_st fmt (Ptset.elements r');
+		  pr ", %b %b %b %b\n%!" rb rb1 rb2 mark
+		in *)
+		let _ = res.(i) <- merge rb rb1 rb2 mark t res1.(i) res2.(i) 
+		in		  
+		  fold ll1 ll2 fll (i+1) (cons r' aq)
+	    | Nil, Nil,[] -> aq,res
+	    | _ -> assert false
+	  in
+	    fold sl1 sl2 fll 0 Nil
+	in
+	let null_result() = (pempty,Array.make slot_size RS.empty) in
+	let rec loop t slist ctx = 
+	  let (a,b) = 
+	  if Tree.is_nil t then null_result()
+	  else	    
+	    let tag = Tree.tag t in
+	    let fl_list,llist,rlist,first,next = get_trans slist tag a t in
+(*	    let _ = pr "For tag %s,node %s, returning formulae list: \n%!"
+	      (Tag.to_string tag) (Tree.dump_node t);
+	      List.iter (fun f -> Formlist.pr fmt f;pr "\n%!") fl_list
+	    in*)
+	    let sl1,res1 = loop (first t) llist t in
+	    let sl2,res2 = loop (next t ctx) rlist ctx in
+	      eval_fold2_slist fl_list sl1 sl2 res1 res2 t	    
+	  in 
+(*	  let _ = pr "Inside topdown call: tree was %s, tag = %s" (Tree.dump_node t) (if Tree.is_nil t then "###" 
+										      else Tag.to_string (Tree.tag t));
+	    iter_pl (fun s -> (pr_st fmt (Ptset.elements s))) a;
+	    Array.iter (fun i -> pr "%i" (RS.length i)) b;
+	    pr "\n%!"; in*) (a,b)
+	    
+	in
+	let loop_no_right t slist ctx =
+	  if Tree.is_nil t then null_result()
+	  else	    
+	    let tag = Tree.tag t in
+	    let fl_list,llist,rlist,first,next = get_trans slist tag a t in
+	    let sl1,res1 = loop (first t) llist t in
+	    let sl2,res2 = null_result() in
+	      eval_fold2_slist fl_list sl1 sl2 res1 res2 t
+	in
+	  (if noright then loop_no_right else loop) t slist ctx
+	    
+	let run_top_down a t =
+	  let init = cons a.init Nil in
+	  let _,res = top_down a t init t 1 
+	  in res.(0)
+	;;
+
+	module Configuration =
+	struct
+	  module Ptss = Set.Make(Ptset)
+	  module IMap = Map.Make(Ptset)
+	  type t = { hash : int;
+			sets : Ptss.t;
+			results : RS.t IMap.t }
+	  let empty = { hash = 0;
+			sets = Ptss.empty;
+			results = IMap.empty;
+		      }
+	  let is_empty c = Ptss.is_empty c.sets
+	  let add c s r =
+	    if Ptss.mem s c.sets then
+	      { c with results = IMap.add s (RS.concat r (IMap.find s c.results)) c.results}
+	    else
+	      { hash = HASHINT2(c.hash,Ptset.hash s);
+		sets = Ptss.add s c.sets;
+		results = IMap.add s r c.results
+	      }
+
+	  let pr fmt c = Format.fprintf fmt "{";
+	    Ptss.iter (fun s -> pr_st fmt (Ptset.elements s);
+			Format.fprintf fmt "  ") c.sets;
+	    Format.fprintf fmt "}\n%!";
+	    IMap.iter (fun k d -> 
+			 pr_st fmt (Ptset.elements k);
+			 Format.fprintf fmt "-> %i\n" (RS.length d)) c.results;			 
+	    Format.fprintf fmt "\n%!"
+	    
+	  let merge c1 c2  =
+ 	    let acc1 = IMap.fold (fun s r acc -> 
+				    IMap.add s
+				      (try 
+					 RS.concat r (IMap.find s acc)
+				       with
+					 | Not_found -> r) acc) c1.results IMap.empty 
+	    in
+	    let imap =
+	      IMap.fold (fun s r acc -> 
+			   IMap.add s
+			     (try 
+				RS.concat r (IMap.find s acc)
+			      with
+				| Not_found -> r) acc)  c2.results acc1
+	    in
+	    let h,s =
+	      Ptss.fold 
+		(fun s (ah,ass) -> (HASHINT2(ah,Ptset.hash s),
+				    Ptss.add s ass))
+		(Ptss.union c1.sets c2.sets) (0,Ptss.empty)
+	    in
+	      { hash = h;
+		sets =s;
+		results = imap }
+
+	end
+
+	let h_fold = Hashtbl.create 511 
+
+	let fold_f_conf  t slist fl_list conf dir= 
+	  let rec loop sl fl acc =
+	    match sl,fl with
+	      |Nil,[] -> acc
+	      | Cons(s,hs,sll), formlist::fll ->
+		  let r',rb,rb1,rb2,mark = 
+		    try 
+		      Hashtbl.find h_fold (hs,Formlist.hash formlist,dir)
+		    with
+			Not_found -> let res = 
+			  if dir then eval_formlist ~memo:false s Ptset.empty formlist
+			  else eval_formlist ~memo:false Ptset.empty s formlist 
+			in (Hashtbl.add h_fold (hs,Formlist.hash formlist,dir) res;res)
+		  in(*
+		  let _ = pr "Evaluating on set (%s) with tree %s=%s" 
+		    (if dir then "left" else "right")
+		    (Tag.to_string (Tree.tag t))
+		    (Tree.dump_node t) ;
+		    pr_st fmt (Ptset.elements s);
+		    pr ", formualae (with hash %i): \n" (Formlist.hash formlist);
+		    Formlist.pr fmt formlist;
+		    pr "result is ";
+		    pr_st fmt (Ptset.elements r');
+		    pr " %b %b %b %b \n%!" rb rb1 rb2 mark ; 
+		  in *)
+		    if rb && ((dir&&rb1)|| ((not dir) && rb2))
+		    then 
+		      let acc = 
+			let old_r = 
+			  try Configuration.IMap.find s conf.Configuration.results
+			  with Not_found -> RS.empty
+			in
+			  Configuration.add acc r' (if mark then RS.cons t old_r else old_r)			
+		      in
+			loop sll fll acc
+		    else loop sll fll acc
+	      | _ -> assert false
+	  in
+	    loop slist fl_list Configuration.empty
+
+	let h_trans = Hashtbl.create 4096
+
+	let get_up_trans slist ptag a tree =	  
+	  let key = (HASHINT2(hpl slist,Tag.hash ptag)) in
+	    try
+	  Hashtbl.find h_trans key		
+	  with
+	  | Not_found ->  
+	  let f_list,_ =
+	    Hashtbl.fold (fun q l acc ->
+			    List.fold_left (fun  (fl_acc,h_acc) (ts,(m,f,_))  ->
+					      if TagSet.mem ptag ts				       
+					      then
+						let h_acc = HASHINT3(h_acc,f.fid,HASHINT2(q,vb m)) in
+						  (Formlist.cons q f h_acc m fl_acc,
+						   h_acc)
+					      else (fl_acc,h_acc))
+	    		      acc l)
+	      a.phi (Formlist.nil,0)
+	  in
+	  let res = fold_pl (fun _ _ acc -> f_list::acc) slist [] 
+	  in
+	    (Hashtbl.add h_trans key res;res) 
+		      
+	      
+	let h_tdconf = Hashtbl.create 511 
+	let rec bottom_up a tree conf next jump_fun root dotd init accu = 
+	  if (not dotd) && (Configuration.is_empty conf ) then
+(*	    	    let _ = pr "Returning early from %s, with accu %i, next is %s\n%!" 
+		    (Tree.dump_node tree) (Obj.magic accu) (Tree.dump_node next)
+		    in *)
+	    accu,conf,next 
+	  else
+(*	    let _ =   
+	    pr "Going bottom up for tree with tag %s configuration is" 
+	    (if Tree.is_nil tree then "###" else Tag.to_string (Tree.tag tree));
+	    Configuration.pr fmt conf 
+	    in *)
+	    let below_right = Tree.is_below_right tree next in 
+	      (*	  let _ = Format.fprintf Format.err_formatter "below_right %s %s = %b\n%!"
+			  (Tree.dump_node tree) (Tree.dump_node next)  below_right
+			  in *)
+	    let accu,rightconf,next_of_next = 	    
+	    if below_right then (* jump to the next *)
+(*	      let _ = pr "Jumping to %s tag %s\n%!" (Tree.dump_node next) (Tag.to_string (Tree.tag next)) in   *)
+	      bottom_up a next conf (jump_fun next) jump_fun (Tree.next_sibling tree) true init accu
+	    else accu,Configuration.empty,next
+	  in 
+(*	  let _ = if below_right then pr "Returning from jump to next = %s\n" (Tree.dump_node next)in   *)
+	  let sub =
+	    if dotd then
+	      if below_right then (* only recurse on the left subtree *)
+(*		let _ = pr "Topdown on left subtree\n%!" in      *)
+		prepare_topdown a tree true
+	      else 
+(*		let _ = pr "Topdown on whole tree\n%!" in *)
+		prepare_topdown a tree false
+	    else conf
+	  in
+	  let conf,next =
+	    (Configuration.merge rightconf sub, next_of_next)
+	  in
+	    if Tree.equal tree root then 
+(*	        let _ = pr "Stopping at root, configuration after topdown is:" ;
+		Configuration.pr fmt conf;
+		pr "\n%!" 		
+	      in *)  accu,conf,next 
+	    else	      
+	  let parent = Tree.binary_parent tree in
+	  let ptag = Tree.tag parent in
+	  let dir = Tree.is_left tree in
+	  let slist = Configuration.Ptss.fold (fun e a -> cons e a) conf.Configuration.sets Nil in
+	  let fl_list = get_up_trans slist ptag a parent in
+	  let slist = rev_pl (slist) in 
+(*	  let _ = pr "Current conf is : %s " (Tree.dump_node tree); 
+	    Configuration.pr fmt conf;
+	    pr "\n" 
+	  in *)
+	  let newconf = fold_f_conf parent slist fl_list conf dir in
+(*	  let _ = pr "New conf before pruning is (dir=%b):" dir;
+	    Configuration.pr fmt newconf ;
+	    pr "accu is %i\n" (RS.length accu);
+	  in 	    *)
+	  let accu,newconf = Configuration.IMap.fold (fun s res (ar,nc) ->
+							if Ptset.intersect s init then
+							  ( RS.concat res ar ,nc)
+							else (ar,Configuration.add nc s res))
+	    (newconf.Configuration.results) (accu,Configuration.empty) 
+	  in
+(*	  let _ = pr "New conf after pruning is (dir=%b):" dir;
+	    Configuration.pr fmt newconf ;
+	    pr "accu is %i\n" (RS.length accu);
+	  in 	    *)
+	    bottom_up a parent newconf next jump_fun root false init accu
+
+	and prepare_topdown a t noright =
+	  let tag = Tree.tag t in
+(*	  pr "Going top down on tree with tag %s = %s "  
+	    (if Tree.is_nil t then "###" else (Tag.to_string(Tree.tag t))) (Tree.dump_node t); *)
+ 	  let r = 
+	    try
+	      Hashtbl.find h_tdconf tag
+	    with
+	      | Not_found -> 
+		  let res = Hashtbl.fold (fun q l acc -> 
+					    if List.exists (fun (ts,_) -> TagSet.mem tag ts) l
+					    then Ptset.add q acc
+					    else acc) a.phi Ptset.empty
+		  in Hashtbl.add h_tdconf tag res;res
+	  in 
+(*	  let _ = pr ", among ";
+	    pr_st fmt (Ptset.elements r);
+	    pr "\n%!";
+	  in *)
+	  let r = cons r Nil in
+	  let set,res = top_down (~noright:noright) a t r t 1 in
+	  let set = match set with
+	    | Cons(x,_,Nil) ->x
+	    | _ -> assert false 
+	  in 
+(*	    pr "Result of topdown run is %!";
+	    pr_st fmt (Ptset.elements set);
+	    pr ", number is %i\n%!" (RS.length res.(0));  *)
+	    Configuration.add Configuration.empty set res.(0) 
+
+
+
+	let run_bottom_up a t k =
+	  let trlist = Hashtbl.find a.phi (Ptset.choose a.init)
+	  in
+	  let init = List.fold_left 
+	    (fun acc (_,(_,f,_)) ->
+	       Ptset.union acc (let (_,_,l) = fst (f.st) in l))
+	    Ptset.empty trlist
+	  in
+	  let tree1,jump_fun =
+	    match k with
+	      | `TAG (tag) -> 
+		  (*Tree.tagged_lowest t tag, fun tree -> Tree.tagged_next tree tag*)
+		  (Tree.tagged_desc tag t, fun tree -> Tree.tagged_foll_below tag tree t)
+	      | `CONTAINS(_) -> (Tree.text_below t,fun tree -> Tree.text_next tree t)
+	      | _ -> assert false
+	  in
+	  let tree2 = jump_fun tree1 in
+	  let rec loop tree next acc = 
+(*	    let _ = pr "\n_________________________\nNew iteration\n" in 
+	    let _ = pr "Jumping to %s\n%!" (Tree.dump_node tree) in  *)
+	    let acc,conf,next_of_next = bottom_up a tree 
+	      Configuration.empty next jump_fun (Tree.root tree) true init acc
+	    in 
+	      (*	    let _ = pr "End of first iteration, conf is:\n%!";
+			    Configuration.pr fmt conf 
+			    in *)	      
+	    let acc = Configuration.IMap.fold 
+	      ( fun s res acc -> if Ptset.intersect init s
+		then RS.concat res acc else acc) conf.Configuration.results acc
+	    in
+	      if Tree.is_nil next_of_next  (*|| Tree.equal next next_of_next *)then
+		acc
+	      else loop next_of_next (jump_fun next_of_next) acc
+	  in
+	  loop tree1 tree2 RS.empty
+
+
+    end
+          
+    let top_down_count a t = let module RI = Run(Integer) in Integer.length (RI.run_top_down a t)
+    let top_down a t = let module RI = Run(IdSet) in (RI.run_top_down a t)
+    let bottom_up_count a t k = let module RI = Run(Integer) in Integer.length (RI.run_bottom_up a t k)
+
+