X-Git-Url: http://matita.cs.unibo.it/gitweb/?a=blobdiff_plain;f=ocaml%2Flambda4.ml;h=c6cecec5c0c064f972071344d4c6381559a4b120;hb=refs%2Fheads%2Fmaster;hp=8a5797ce1297491837bec242c6565b7a7481c767;hpb=d3e73f866de30503a4c44d67cdd9e8ff77c15fc3;p=fireball-separation.git

diff --git a/ocaml/lambda4.ml b/ocaml/lambda4.ml
index 8a5797c..c6cecec 100644
--- a/ocaml/lambda4.ml
+++ b/ocaml/lambda4.ml
@@ -11,7 +11,10 @@ let bomb = ref(`Var(-1,-666));;
  For Scott's encoding, two.
 *)
 let num_more_args = 2;;
+(* verbosity *)
 let _very_verbose = false;;
+(** Display measure of every term when printing problem *)
+let _measure_of_terms = false;;
 
 let verbose s =
  if _very_verbose then prerr_endline s
@@ -46,16 +49,18 @@ let all_terms p =
  @ p.ps
 ;;
 
-let sum_arities p =
+let measure_of_term, measure_of_terms =
  let rec aux = function
  | `N _ -> 0
  | `Var(_,ar) -> if ar = min_int then 0 else max 0 ar (*assert (ar >= 0); ar*)
  | `Lam(_,t) -> aux t
- | `I(v,args) -> aux (`Var v) + aux_many (Listx.to_list args)
- | `Match(u,(_,ar),_,_,args) -> aux (u :> nf) + (if ar = min_int then 0 else ar - 1) + aux_many args
+ | `I(v,args) -> aux (`Var v) + aux_many (Listx.to_list args :> nf list)
+ | `Match(u,(_,ar),_,_,args) -> aux (u :> nf) + (if ar <= 0 then 0 else ar - 1) + aux_many args
  and aux_many tms = List.fold_right ((+) ++ aux) tms 0 in
- aux_many (all_terms p :> nf list)
- ;;
+ (fun t -> aux (t :> nf)), (fun l -> aux_many (l :> nf list))
+;;
+
+let sum_arities p = measure_of_terms (all_terms p)
 
 let count_fakevars p =
  let rec aux = function
@@ -75,6 +80,7 @@ let problem_measure p = sum_arities p;;
 let string_of_measure = string_of_int;;
 
 let string_of_problem label ({freshno; div; conv; ps; deltas} as p) =
+ let aux_measure_terms t = if _measure_of_terms then "(" ^ string_of_int (measure_of_term t) ^ ") " else "" in
  let deltas = String.concat ("\n#  ") (List.map (fun r -> String.concat " <> " (List.map (fun (i,_) -> string_of_int i) !r)) deltas) in
  let l = p.var_names in
  String.concat "\n" ([
@@ -86,10 +92,10 @@ let string_of_problem label ({freshno; div; conv; ps; deltas} as p) =
    ) else "# ";
   "#";
   "$" ^ p.label;
-  (match div with None -> "# no D" | Some div -> "D " ^ print ~l (div :> nf));
+  (match div with None -> "# D" | Some div -> "D " ^ aux_measure_terms div ^ print ~l (div :> nf));
   ]
-  @ List.map (fun t -> "C " ^ (if t = convergent_dummy then "#C" else "C " ^ print ~l (t :> nf))) conv
-  @ List.mapi (fun i t -> string_of_int i ^ " " ^ print ~l (t :> nf)) ps
+  @ List.map (fun t -> if t = convergent_dummy then "# C" else "C " ^ aux_measure_terms t ^ print ~l (t :> nf)) conv
+  @ List.mapi (fun i t -> string_of_int i ^ " " ^ aux_measure_terms t ^ print ~l (t :> nf)) ps
   @ [""])
 ;;
 
@@ -252,10 +258,9 @@ List.iter (fun x -> prerr_endline ("IN2: " ^ print (fst x :> nf))) super_simplif
 
 exception Dangerous
 
-let arity_of arities k =
- let _,pos,y = List.find (fun (v,_,_) -> v=k) arities in
- let arity = match y with `Var _ -> 0 | `I(_,args) -> Listx.length args | `N _ -> assert false in
- arity + if pos = -1 then - 1 else 0
+let arity_of arities hd =
+ let pos,_,nargs = List.find (fun (_,hd',_) -> hd=hd') arities in
+ nargs + if pos = -1 then - 1 else 0
 ;;
 
 let rec dangerous arities showstoppers =
@@ -354,13 +359,21 @@ List.iter (fun l -> prerr_endline (String.concat " " (List.map (string_of_var p.
 ;;
 
 let precompute_edible_data {ps; div} xs =
- (match div with None -> [] | Some div -> [hd_of_i_var div, -1, (div :> i_n_var)]) @
-  List.map (fun hd ->
+ let aux t = match t with `Var _ -> 0 | `I(_, args) -> Listx.length args | `N _ -> assert false in
+ (fun l -> match div with
+  | None -> l
+  | Some div -> (-1, hd_of_i_var div, aux div) :: l)
+  (List.map (fun hd ->
    let i, tm = Util.findi (fun y -> hd_of y = Some hd) ps in
-    hd, i, tm
-   ) xs
+    i, hd, aux tm
+   ) xs)
 ;;
 
+(** Returns (p, showstoppers_step, showstoppers_eat) where:
+    - showstoppers_step are the heads occurring twice
+      in the same discriminating set
+    - showstoppers_eat are the heads in ps having different number
+      of arguments *)
 let critical_showstoppers p =
   let p = super_simplify p in
   let hd_of_div = match p.div with None -> [] | Some t -> [hd_of_i_var t] in
@@ -400,30 +413,28 @@ let eat p =
   let showstoppers = showstoppers_step @ showstoppers_eat in
   let heads = List.sort compare (filter_map hd_of ps) in
   let arities = precompute_edible_data p (uniq heads) in
-  let showstoppers, showstoppers_conv =
-   edible p arities showstoppers in
-  let l = List.filter (fun (x,_,_) -> not (List.mem x showstoppers)) arities in
+  let inedible, showstoppers_conv = edible p arities showstoppers in
+  let l = List.filter (fun (_,hd,_) -> not (List.mem hd inedible)) arities in
   let p =
-  List.fold_left (fun p (x,pos,(xx : i_n_var)) -> if pos = -1 then p else
-   let n = match xx with `I(_,args) -> Listx.length args | _ -> 0 in
-   let v = `N(pos) in
-   let inst = make_lams v n in
-prerr_endline ("# INST_IN_EAT: " ^ string_of_var p.var_names x ^ " := " ^ string_of_term p inst);
-   { p with sigma = p.sigma @ [x,inst] }
+  List.fold_left (fun p (pos,hd,nargs) -> if pos = -1 then p else
+   let v = `N pos in
+   let inst = make_lams v nargs in
+prerr_endline ("# INST_IN_EAT: " ^ string_of_var p.var_names hd ^ " := " ^ string_of_term p inst);
+   { p with sigma = p.sigma @ [hd,inst] }
    ) p l in
   (* to avoid applied numbers in safe positions that
      trigger assert failures subst_in_problem x inst p*)
  let ps =
   List.map (fun t ->
    try
-    let _,j,_ = List.find (fun (h,_,_) -> hd_of t = Some h) l in
+    let j,_,_ = List.find (fun (_,hd,_) -> hd_of t = Some hd) l in
     `N j
    with Not_found -> t
   ) ps in
  let p = match p.div with
   | None -> p
   | Some div ->
-   if List.mem (hd_of_i_var div) showstoppers
+   if List.mem (hd_of_i_var div) inedible
    then p
    else
     let n = match div with `I(_,args) -> Listx.length args | `Var _ -> 0 in
@@ -440,14 +451,14 @@ prerr_endline ("# INST_IN_EAT: " ^ string_of_var p.var_names x ^ " := " ^ string
     (* subst_in_problem (hd_of_i_var div) inst p in *)
      {p with sigma=p.sigma@[x,inst]} in
      let dangerous_conv = showstoppers_conv in
-let _ = prerr_endline ("dangerous_conv lenght:" ^ string_of_int (List.length dangerous_conv));
-List.iter (fun l -> prerr_endline (String.concat " " (List.map (string_of_var p.var_names) l))) dangerous_conv; in
+prerr_endline ("dangerous_conv lenght:" ^ string_of_int (List.length dangerous_conv));
+List.iter (fun l -> prerr_endline (String.concat " " (List.map (string_of_var p.var_names) l))) dangerous_conv;
  let conv =
    List.map (function s,t ->
     try
      if s <> [] then t else (
      (match t with | `Var _ -> raise Not_found | _ -> ());
-     let _ = List.find (fun h -> hd_of t = Some h) showstoppers in
+     let _ = List.find (fun h -> hd_of t = Some h) inedible in
       t)
     with Not_found -> match hd_of t with
      | None -> assert (t = convergent_dummy); t
@@ -503,7 +514,16 @@ let compute_special_k tms =
      List.fold_left max 0 (List.map (aux 0) ((t :> nf)::args@List.map snd !bs))
  | `N _
  | `Var _ -> 0
- ) in Listx.max (Listx.map (aux 0) tms)
+ ) in
+ let rec aux' top t = match t with
+ | `Lam(_,t) -> aux' false t
+ | `I((_,ar), tms) -> max ar
+     (Listx.max (Listx.map (aux' false) (tms :> nf Listx.listx)))
+ | `Match(t, _, liftno, bs, args) ->
+     List.fold_left max 0 (List.map (aux' false) ((t :> nf)::(args :> nf list)@List.map snd !bs))
+ | `N _
+ | `Var _ -> 0 in
+ Listx.max (Listx.map (aux 0) tms) + Listx.max (Listx.map (aux' true) tms)
 ;;
 
 let auto_instantiate (n,p) =
@@ -530,36 +550,6 @@ let auto_instantiate (n,p) =
   | x::_, _ ->
       prerr_endline ("INSTANTIATING " ^ string_of_var p.var_names x);
       x in
-(* Strategy that  decreases the special_k to 0 first (round robin)
-1:11m42 2:14m5 3:11m16s 4:14m46s 5:12m7s 6:6m31s *)
- let x =
-  try
-   match
-    hd_of (List.find (fun t ->
-     compute_special_k (Listx.Nil (t :> nf)) > 0 && arity_of_hd t > 0
-     ) (all_terms p))
-   with
-    | None -> assert false
-    | Some x ->
-       prerr_endline ("INSTANTIATING AND HOPING " ^ string_of_var p.var_names x);
-       x
-  with
-   Not_found ->
-    let arity_of_x = max_arity_tms x (all_terms p) in
-    assert (Util.option_get arity_of_x > 0);
-    x in
-(* Instantiate in decreasing order of compute_special_k
-1:15m14s 2:13m14s 3:4m55s 4:4m43s 5:4m34s 6:6m28s 7:3m31s
-let x =
- try
-  (match hd_of (snd (List.hd (List.sort (fun c1 c2 -> - compare (fst c1) (fst c2)) (filter_map (function `I _ as t -> Some (compute_special_k (Listx.Nil (t :> nf)),t) | _ -> None) (all_terms p))))) with
-      None -> assert false
-    | Some x ->
-       prerr_endline ("INSTANTIATING AND HOPING " ^ string_of_var x);
-       x)
- with
-  Not_found -> x
-in*)
  let special_k =
      compute_special_k (Listx.from_list (all_terms p :> nf list) )in
  if special_k < n then
@@ -667,9 +657,9 @@ let env_of_sigma freshno sigma should_explode =
     e,Pure.lift (-n-1) (snd (List.find (fun (i,_) -> i = n) sigma)),[]
    with
     Not_found ->
-     if should_explode && n = hd_of_i_var (cast_to_i_var !bomb)
-      then ([], (let f t = Pure.A(t,t) in f (Pure.L (f (Pure.V 0)))), [])
-      else ([],Pure.V n,[]))::e
+    if n = hd_of_i_var (cast_to_i_var !bomb)
+     then ([], Pure.omega should_explode, [])
+     else ([], Pure.V n, []) ) :: e
  in aux 0
 ;;
 (* ************************************************************************** *)
@@ -722,22 +712,22 @@ let solve p =
  let ps = List.map scott_of_nf p.ps in
 
  let sigma' = List.map (fun (x,inst) -> x, scott_of_nf inst) sigma in
- let e' = env_of_sigma freshno sigma' false (* FIXME shoudl_explode *) in
+ let e' = env_of_sigma freshno sigma' false in
+ let e'' = env_of_sigma freshno sigma' true in
 
  prerr_endline "--------<REDUCE>---------";
- let pure_bomb = ToScott.t_of_nf (!bomb) in (* Pure.B *)
  (function
    | Some div ->
       print_endline (Pure.print div);
       let t = Pure.mwhd (e',div,[]) in
       prerr_endline ("*:: " ^ (Pure.print t));
-      assert (t = pure_bomb)
+      assert (Pure.diverged t)
    | None -> ()) div;
  List.iter (fun n ->
   verbose ("_::: " ^ (Pure.print n));
-  let t = Pure.mwhd (e',n,[]) in
+  let t = Pure.mwhd (e'',n,[]) in
   verbose ("_:: " ^ (Pure.print t));
-  assert (t <> pure_bomb)
+  assert (not (Pure.diverged t))
  ) conv ;
  List.iteri (fun i n ->
   verbose ((string_of_int i) ^ "::: " ^ (Pure.print n));