merge from branch stable-succint-jumping

[SXSI/xpathcomp.git] / ptset.ml

diff --git a/ptset.ml b/ptset.ml
index 3d30f68..4b2c845 100644 (file)
--- a/ptset.ml
+++ b/ptset.ml
@@ -11,26 +11,32 @@ type elt = int
 
 type t = { id : int;
           key : int; (* hash *)
-          node : node }
+          node : node;
+          }
 and node = 
   | Empty
   | Leaf of int
   | Branch of int * int * t * t
 
+
+(* faster if outside of a module *)
+let hash_node x = match x with 
+  | Empty -> 0
+  | Leaf i -> (i+1) land max_int
+      (* power of 2 +/- 1 are fast ! *)
+  | Branch (b,i,l,r) -> 
+      ((b lsl 1)+ b + i+(i lsl 4) + (l.key lsl 5)-l.key
+       + (r.key lsl 7) - r.key) land max_int
+
 module Node = 
   struct
     type _t = t
     type t = _t
-    let hash x = x.key       
-    let hash_node = function 
-        | Empty -> 0
-        | Leaf i -> i+1
-            (* power of 2 +/- 1 are fast ! *)
-        | Branch (b,i,l,r) -> 
-            (b lsl 1)+ b + i+(i lsl 4) + (l.key lsl 5)-l.key
-            + (r.key lsl 7) - r.key
-    let hash_node x = (hash_node x) land max_int
-    let equal x y = match (x.node,y.node) with
+    external hash : t -> int = "%field1"
+    let equal x y = 
+      if x.id == y.id || x.key == y.key || x.node == y.node then true
+      else
+      match (x.node,y.node) with
       | Empty,Empty -> true
       | Leaf k1, Leaf k2 when k1 == k2 -> true
       | Branch(p1,m1,l1,r1), Branch(p2,m2,l2,r2) when m1==m2 && p1==p2 && 
@@ -62,7 +68,7 @@ let is_empty s = s.id==0
     
 let rec norm n =
   let v = { id = gen_uid ();
-           key = Node.hash_node n;
+           key = hash_node n;
            node = n } 
   in
       WH.merge pool v 
@@ -368,3 +374,32 @@ let rec intersect s1 s2 = (equal s1 s2) ||
 let hash s = s.key
 
 let from_list l = List.fold_left (fun acc i -> add i acc) empty l
+
+type int_vector
+
+external int_vector_alloc : int -> int_vector = "caml_int_vector_alloc"
+external int_vector_set : int_vector -> int -> int -> unit = "caml_int_vector_set"
+external int_vector_length : int_vector -> int  = "caml_int_vector_length"
+external int_vector_empty : unit -> int_vector = "caml_int_vector_empty"
+
+let empty_vector = int_vector_empty ()
+
+let to_int_vector_ext s =
+  let l = cardinal s in
+  let v = int_vector_alloc l in
+  let i = ref 0 in
+    iter (fun e -> int_vector_set v !i e; incr i) s;
+    v
+
+let hash_vectors = Hashtbl.create 4097
+
+let to_int_vector s =
+  try 
+    Hashtbl.find hash_vectors s.key
+  with
+      Not_found -> 
+       let v = to_int_vector_ext s in
+         Hashtbl.add hash_vectors s.key v;
+         v
+
+