X-Git-Url: http://matita.cs.unibo.it/gitweb/?a=blobdiff_plain;f=helm%2Fsoftware%2Flambda-delta%2Fbasic_rg%2FbrgReduction.ml;h=87d093d82f47638ea9580a89996d7f632482e0d6;hb=75d417a2bb12a56052dd520c513c789fd9256252;hp=74f6a504887511303cec3fbe1aeb9163ead41bde;hpb=8659e85d49be1ad72622d4d3a73d384b744c3c08;p=helm.git

diff --git a/helm/software/lambda-delta/basic_rg/brgReduction.ml b/helm/software/lambda-delta/basic_rg/brgReduction.ml
index 74f6a5048..87d093d82 100644
--- a/helm/software/lambda-delta/basic_rg/brgReduction.ml
+++ b/helm/software/lambda-delta/basic_rg/brgReduction.ml
@@ -11,191 +11,198 @@
 
 module U = NUri
 module C = Cps
-module S = Share
 module L = Log
+module P = Output
 module B = Brg
+module O = BrgOutput
 module E = BrgEnvironment
+module S = BrgSubstitution
 
-type environment = int * B.bind list
+exception LRefNotFound of B.message
 
-type stack = B.term list
-
-type context = {
-   g: environment;
-   l: environment;
-   s: stack
+type machine = {
+   c: B.context;
+   s: (B.term * int) list
 }
 
-exception LRefNotFound of (context, B.term) L.item list
-
-type whd_result =
-   | Sort_ of int
-   | LRef_ of int * B.term option
-   | GRef_ of int * B.bind
-   | Bind_ of B.term * B.term
-
-type ho_whd_result =
-   | Sort of int
-   | Abst of B.term
-
 (* Internal functions *******************************************************)
 
+let level = 5
+
 let error i = raise (LRefNotFound (L.items1 (string_of_int i)))
 
-let empty_e = 0, []
+let log1 s c t =
+   let sc, st = s ^ " in the context", "the term" in
+   L.log O.specs level (L.ct_items1 sc c st t)
 
-let push_e f b (l, e) =
-   f (succ l, b :: e)
+let log2 s c u t =
+   let sc, su, st = s ^ " in the context", "the term", "and the term" in
+   L.log O.specs level (L.ct_items2 sc c su u st t)
 
-let get_e f c i =
-   let (gl, ge), (ll, le) = c.g, c.l in
-   if i >= gl + ll then error i;
-   let b =
-      if i < gl then List.nth ge (gl - (succ i)) 
-      else List.nth le (gl + ll - (succ i))
-   in
-   f b
-
-let rec lref_map_bind f map b = match b with
-   | B.Abbr v ->
-      let f v' = f (S.sh1 v v' b B.abbr) in
-      lref_map f map v      
-   | B.Abst w ->
-      let f w' = f (S.sh1 w w' b B.abst) in
-      lref_map f map w
-   | B.Void   -> f b
-
-and lref_map f map t = match t with
-   | B.LRef i          -> f (B.LRef (map i))
-   | B.GRef _          -> f t
-   | B.Sort _          -> f t
-   | B.Cast (w, u)     ->
-      let f w' u' = f (S.sh2 w w' u u' t B.cast) in
-      let f w' = lref_map (f w') map u in 
-      lref_map f map w
-   | B.Appl (w, u)     ->
-      let f w' u' = f (S.sh2 w w' u u' t B.appl) in
-      let f w' = lref_map (f w') map u in 
-      lref_map f map w
-   | B.Bind (id, b, u) ->
-      let f b' u' = f (S.sh2 b b' u u' t (B.bind id)) in
-      let f b' = lref_map (f b') map u in 
-      lref_map_bind f map b
+let empty_machine = {
+   c = B.empty_context; s = []
+}
 
-(* to share *)
-let lift f c = 
-   let (gl, _), (ll, le) = c.g, c.l in
-   let map i = if i >= gl then succ i else i in
-   let map f = function
-      | B.Abbr t -> let f t' = f (B.Abbr t') in lref_map f map t
-      | _       -> assert false
-   in
-   let f le' = f {c with l = (ll, le')} in
-   C.list_map f map le
-
-let xchg f c t =
-   let (gl, _), (ll, _) = c.g, c.l in
-   let map i =
-      if i < gl || i > gl + ll then i else
-      if i >= gl && i < gl + ll then succ i else gl
+let get f c m i =
+   let f e = function
+      | Some (_, b) -> f e b
+      | None        -> error i
    in
-   lref_map (f c) map t
+   let f c = B.get f c i in
+   B.append f c m.c
+
+let lift_stack f s =
+   let map f (v, i) = f (v, succ i) in
+   Cps.list_map f map s
+
+let unwind_to_term f m t =
+   let map f t (a, b) = f (B.Bind (a, b, t)) in
+   let f mc = C.list_fold_left f map t mc in
+   assert (m.s = []);
+   B.contents f m.c
+
+let push f m a b = 
+   assert (m.s = []);
+   f {m with c = (a, b) :: m.c}
 
 (* to share *)
-let rec whd f c t = match t with
-   | B.Sort h                 -> f c (Sort_ h)
-   | B.GRef uri               ->
-      let f (i, _, b) = f c (GRef_ (i, b)) in
-      E.get_obj f uri
-   | B.LRef i                ->
+let rec step f ?(delta=false) ?(rt=false) c m x = 
+(*   L.warn "entering R.step"; *)
+   match x with
+   | B.Sort _                -> f m x
+   | B.GRef (a, uri)         ->
       let f = function
-         | B.Void   -> f c (LRef_ (i, None))
-	 | B.Abst t -> f c (LRef_ (i, Some t))
-	 | B.Abbr t -> whd f c t
+         | _, _, B.Abbr v when delta ->
+            P.add ~gdelta:1 ();
+	    step f ~delta ~rt c m v
+         | _, _, B.Abst w when rt   ->
+            P.add ~grt:1 ();
+	    step f ~delta ~rt c m w	 
+	 | e, _, b                   ->
+	    f m (B.GRef (B.Entry (e, b) :: a, uri))
+      in
+      E.get_obj f uri
+   | B.LRef (a, i)           ->
+      let f e = function
+	 | B.Abbr v          ->
+	    P.add ~ldelta:1 ();
+	    step f ~delta ~rt c m v
+	 | B.Abst w when rt ->
+            P.add ~lrt:1 ();
+            step f ~delta ~rt c m w
+	 | b                 ->
+	    f m (B.LRef (B.Entry (e, b) :: a, i))
       in
-      get_e f c i
-   | B.Cast (_, t)           -> whd f c t
-   | B.Appl (v, t)           -> whd f {c with s = v :: c.s} t   
-   | B.Bind (_, B.Abst w, t) -> 
-      begin match c.s with
-         | []      -> f c (Bind_ (w, t))
-	 | v :: tl -> 
-	    let f tl l = whd f {c with l = l; s = tl} t in
-	    push_e (f tl) (B.Abbr v) c.l
+      let f e = S.lift_bind (f e) (succ i) (0) in 
+      get f c m i
+   | B.Cast (_, _, t)        ->
+      P.add ~tau:1 ();
+      step f ~delta ~rt c m t
+   | B.Appl (_, v, t)        ->
+      step f ~delta ~rt c {m with s = (v, 0) :: m.s} t   
+   | B.Bind (a, B.Abst w, t) -> 
+      begin match m.s with
+         | []           -> f m x
+	 | (v, h) :: tl -> 
+            P.add ~beta:1 ~upsilon:(List.length tl) ();
+	    let f mc sc = step f ~delta ~rt c {c = mc; s = sc} t in
+	    let f mc = lift_stack (f mc) tl in 
+	    let f v = B.push f m.c a (B.Abbr (B.Cast ([], w, v))) in
+	    S.lift f h (0) v
       end
-   | B.Bind (_, b, t) -> 
-      let f l = whd f {c with l = l} t in
-      push_e f b c.l
-
-let push f c t = 
-   assert (c.s = []);
-   let f c g = xchg f {c with g = g} t in
-   let f c = push_e (f c) B.Void c.g in
-   lift f c 
+   | B.Bind (a, b, t)        -> 
+      P.add ~upsilon:(List.length m.s) ();
+      let f sc mc = step f ~delta ~rt c {c = mc; s = sc} t in
+      let f sc = B.push (f sc) m.c a b in
+      lift_stack f m.s
 
 (* Interface functions ******************************************************)
-
-let rec are_convertible f c1 t1 c2 t2 =
-   let rec aux c1' r1 c2' r2 = match r1, r2 with
-      | Sort_ h1, Sort_ h2                           -> f (h1 = h2)
-      | LRef_ (i1, _), LRef_ (i2, _)                 ->
-         if i1 = i2 then are_convertible_stacks f c1' c2' else f false
-      | GRef_ (a1, B.Abst _), GRef_ (a2, B.Abst _)   ->
-         if a1 = a2 then are_convertible_stacks f c1' c2' else f false
-      | GRef_ (a1, B.Abbr v1), GRef_ (a2, B.Abbr v2) ->
-         if a1 = a2 then are_convertible_stacks f c1' c2' else
-	 if a1 < a2 then whd (aux c1' r1) c2' v2 else
-	 whd (aux_rev c2' r2) c1' v1
-      | _, GRef_ (_, B.Abbr v2)                      ->
-         whd (aux c1' r1) c2' v2
-      | GRef_ (_, B.Abbr v1), _                      ->
-	 whd (aux_rev c2' r2) c1' v1
-      | Bind_ (w1, t1), Bind_ (w2, t2)               ->
-         let f b = 
-	    if b then 
-	       let f c1'' t1' = push (are_convertible f c1'' t1') c2' t2 in
-               push f c1' t1
-	    else f false
-	 in
-	 are_convertible f c1' w1 c2' w2
-      | _                                              -> f false
-   and aux_rev c2 r2 c1 r1 = aux c1 r1 c2 r2 in
-   let f c1' r1 = whd (aux c1' r1) c2 t2 in 
-   whd f c1 t1
-
-and are_convertible_stacks f c1 c2 =
-   let map f v1 v2 = are_convertible f c1 v1 c2 v2 in
-   if List.length c1.s <> List.length c2.s then f false else
-   C.forall2 f map c1.s c2.s
-
-let are_convertible f c t1 t2 = are_convertible f c t1 c t2
-
-let rec ho_whd f c t =
-   let aux c' = function
-      | Sort_ h             -> f c' (Sort h)
-      | Bind_ (w, t)        -> f c' (Abst w)
-      | LRef_ (_, Some w)   -> ho_whd f c w
-      | GRef_ (_, B.Abst u) -> ho_whd f c u
-      | GRef_ (_, B.Abbr u) -> ho_whd f c u
-      | LRef_ (_, None)     -> assert false
-      | GRef_ (_, B.Void)   -> assert false
+   
+let domain f c t =
+   let f r = L.unbox level; f r in
+   let f m = function
+      | B.Bind (_, B.Abst w, _) ->
+         let f w = f (Some w) in unwind_to_term f m w
+      | x                       -> f None
    in
-   whd aux c t
-
-let push f c b = 
-   assert (c.l = empty_e && c.s = []);
-   let f g = f {c with g = g} in
-   push_e f b c.g
-
-let get f c i =
-   let gl, ge = c.g in
-   if i >= gl then error i;
-   f (List.nth ge (gl - (succ i)))
-
-let empty_context = {
-   g = empty_e; l = empty_e; s = []
-}
+   L.box level; log1 "Now scanning" c t;
+   step f ~delta:true ~rt:true c empty_machine t
+
+let rec ac_nfs f ~si r c m1 u m2 t =
+(*   L.warn "entering R.are_convertible_aux"; *)
+   log2 "Now converting nfs" c u t;
+   match u, t with
+      | B.Sort (_, h1), B.Sort (_, h2)             ->
+         if h1 = h2 then f r else f false 
+      | B.LRef (B.Entry (e1, B.Abst _) :: _, i1), 
+        B.LRef (B.Entry (e2, B.Abst _) :: _, i2)   ->
+	 P.add ~zeta:(i1+i2-e1-e2) ();
+	 if e1 = e2 then ac_stacks f ~si r c m1 m2 else f false
+      | B.GRef (B.Entry (e1, B.Abst _) :: _, _), 
+        B.GRef (B.Entry (e2, B.Abst _) :: _, _)    ->
+	 if e1 = e2 then ac_stacks f ~si r c m1 m2 else f false
+      | B.GRef (B.Entry (e1, B.Abbr v1) :: _, _), 
+        B.GRef (B.Entry (e2, B.Abbr v2) :: _, _)   ->
+         if e1 = e2 then
+	    let f r = 
+	       if r then f r 
+	       else begin  
+                  P.add ~gdelta:2 ();
+	          ac f ~si true c m1 v1 m2 v2
+	       end
+	    in
+	    ac_stacks f ~si r c m1 m2
+	 else if e1 < e2 then begin 
+            P.add ~gdelta:1 ();
+	    step (ac_nfs f ~si r c m1 u) c m2 v2
+	 end else begin
+	    P.add ~gdelta:1 ();
+	    step (ac_nfs_rev f ~si r c m2 t) c m1 v1
+         end
+      | _, B.GRef (B.Entry (_, B.Abbr v2) :: _, _) ->
+         P.add ~gdelta:1 ();
+         step (ac_nfs f ~si r c m1 u) c m2 v2      
+      | B.GRef (B.Entry (_, B.Abbr v1) :: _, _), _ ->
+         P.add ~gdelta:1 ();
+	 step (ac_nfs_rev f ~si r c m2 t) c m1 v1            
+      | B.Bind (a1, (B.Abst w1 as b1), t1), 
+        B.Bind (a2, (B.Abst w2 as b2), t2)         ->
+	 let g m1 m2 = ac f ~si r c m1 t1 m2 t2 in
+         let g m1 = push (g m1) m2 a2 b2 in 
+	 let f r = if r then push g m1 a1 b1 else f false in
+	 ac f ~si r c m1 w1 m2 w2      
+      | B.Sort _, B.Bind (a, b, t) when si         ->
+	 P.add ~si:1 ();
+	 let f m1 m2 = ac f ~si r c m1 u m2 t in
+	 let f m1 = push (f m1) m2 a b in
+	 push f m1 a b
+      | _                                          -> f false
+
+and ac_nfs_rev f ~si r c m2 t m1 u = ac_nfs f ~si r c m1 u m2 t
+
+and ac f ~si r c m1 t1 m2 t2 =
+(*   L.warn "entering R.are_convertible"; *)
+   let g m1 t1 = step (ac_nfs f ~si r c m1 t1) c m2 t2 in 
+   if r = false then f false else step g c m1 t1
+
+and ac_stacks f ~si r c m1 m2 =
+(*   L.warn "entering R.are_convertible_stacks"; *)
+   let mm1, mm2 = {m1 with s = []}, {m2 with s = []} in
+   let map f r (v1, h1) (v2, h2) =
+      let f v1 = S.lift (ac f ~si r c mm1 v1 mm2) h2 (0) v2 in
+      S.lift f h1 (0) v1
+   in
+   if List.length m1.s <> List.length m2.s then 
+      begin 
+(*         L.warn (Printf.sprintf "Different lengths: %u %u"
+	    (List.length m1.s) (List.length m2.s) 
+	 ); *)
+	 f false
+      end
+   else
+      C.list_fold_left2 f map r m1.s m2.s
 
-let iter f map c =
-   let _, ge = c.g in   
-   C.list_iter f map ge
+let are_convertible f ?(si=false) c u t = 
+   let f b = L.unbox level; f b in
+   L.box level; log2 "Now converting" c u t;
+   ac f ~si true c empty_machine u empty_machine t