X-Git-Url: http://matita.cs.unibo.it/gitweb/?a=blobdiff_plain;ds=sidebyside;f=ocaml%2Flambda4.ml;h=6a534cd2a80297651b84e2e8255fe08ae222d011;hb=632f83a9f7fbf8a09e323314dde76189692d6f07;hp=456dd5b9ec96ae9b62ee68c185067f97cfaa3d5d;hpb=eeb6d213aac0f064babcb31ad6250be842d952b5;p=fireball-separation.git

diff --git a/ocaml/lambda4.ml b/ocaml/lambda4.ml
index 456dd5b..6a534cd 100644
--- a/ocaml/lambda4.ml
+++ b/ocaml/lambda4.ml
@@ -9,12 +9,6 @@ exception Bottom
 exception Lambda
 exception Backtrack of string
 
-(*
- The number of arguments which can applied to numbers
- safely, depending on the encoding of numbers.
- For Scott's encoding, two.
-*)
-let num_more_args = 2;;
 (* verbosity *)
 let _very_verbose = false;;
 (** Display measure of every term when printing problem *)
@@ -283,11 +277,11 @@ List.iter (fun x -> prerr_endline ("IN2: " ^ print (fst x :> nf))) super_simplif
  );
  let p = {p with sigma = sigma@[x,inst]} in
  let p = super_simplify p in
- prerr_endline (string_of_problem "instantiate" p);
  p
 ;;
 
-exception Dangerous
+exception TriggerMatchReduction of int;;
+exception Dangerous;;
 
 let arity_of arities hd =
  let pos,_,nargs = List.find (fun (_,hd',_) -> hd=hd') arities in
@@ -305,8 +299,8 @@ let rec dangerous arities showstoppers =
       (match t with
           `N _ -> List.iter (dangerous arities showstoppers) args
         | `Match _ as t -> dangerous arities showstoppers t ; List.iter (dangerous arities showstoppers) args
-        | `Var(x,_) -> dangerous_inert arities showstoppers x args num_more_args
-        | `I((x,_),args') -> dangerous_inert arities showstoppers x (Listx.to_list args' @ args) num_more_args
+        | `Var(x,_) -> dangerous_inert arities showstoppers x args 2
+        | `I((x,_),args') -> dangerous_inert arities showstoppers x (Listx.to_list args' @ args) 2
       )
   | `I((k,_),args) -> dangerous_inert arities showstoppers k (Listx.to_list args) 0
 
@@ -322,73 +316,75 @@ and dangerous_inert arities showstoppers k args more_args =
 (* cut & paste from above *)
 let rec dangerous_conv p arities showstoppers =
  function
-    `N _
+  | `N _
   | `Var _
   | `Lam _
-  | `Pacman -> []
-  | `Match(t,_,liftno,bs,args) ->
+  | `Pacman -> ()
+  | `Match(t,_,liftno,bs,args) -> (
       (* CSC: XXX partial dependency on the encoding *)
-      (match t with
-          `N _ -> concat_map (dangerous_conv p arities showstoppers) args
-        | `Match _ as t -> dangerous_conv p arities showstoppers t @ concat_map (dangerous_conv p arities showstoppers) args
+       try (match t with
+        | `N _ -> List.iter (dangerous_conv p arities showstoppers) args
+        | `Match _ as t -> dangerous_conv p arities showstoppers t; List.iter (dangerous_conv p arities showstoppers) args
         | `Var(x,_) -> dangerous_inert_conv p arities showstoppers x [] args 2
         | `I((x,_),args') -> dangerous_inert_conv p arities showstoppers x (Listx.to_list args') args 2
-      )
+        ) with TriggerMatchReduction x -> (
+           match Util.find_opt (fun (n, t) -> if hd_of (List.nth p.ps n) = Some x then Some t else None) !bs with
+            | None -> ()
+            | Some t -> (
+               match t with
+                | `Bottom -> raise Dangerous
+                | #nf_nob as t -> dangerous_conv p arities showstoppers t
+               )
+           )
+       )
   | `I((k,_),args) -> dangerous_inert_conv p arities showstoppers k (Listx.to_list args) [] 0
 
 and dangerous_inert_conv p arities showstoppers k args match_args more_args =
  let all_args = args @ match_args in
- let dangerous_args = concat_map (dangerous_conv p arities showstoppers) all_args in
+ List.iter (dangerous_conv p arities showstoppers) all_args;
  let all_args = (all_args :> nf list) in
- if dangerous_args = [] then (
- if List.mem k showstoppers then k :: concat_map free_vars all_args else
- try
-  let arity = arity_of arities k in
-prerr_endline ("dangerous_inert_conv: ar=" ^ string_of_int arity ^ " k="^string_of_var p.var_names k ^ " listlenargs=" ^ (string_of_int (List.length args)) ^ " more_args=" ^ string_of_int more_args);
-  if more_args > 0 (* match argument*) && List.length args = arity then []
-  else if List.length all_args + more_args > arity then k :: concat_map free_vars all_args else []
- with
-  Not_found -> []
- ) else k :: concat_map free_vars all_args
+ if List.mem k showstoppers then raise Dangerous else
+  try
+   let arity = arity_of arities k in
+(* prerr_endline ("dangerous_inert_conv: ar=" ^ string_of_int arity ^ " k="^string_of_var p.var_names k ^ " listlenargs=" ^ (string_of_int (List.length args)) ^ " more_args=" ^ string_of_int more_args); *)
+   if more_args > 0 (* match argument*) && List.length args = arity then raise (TriggerMatchReduction k)
+    else if List.length all_args + more_args > arity then raise Dangerous else ()
+  with
+   Not_found -> ()
 
 (* inefficient algorithm *)
-let rec edible ({div; conv; ps} as p) arities showstoppers =
- let rec aux showstoppers =
-  function
-     [] -> showstoppers
+let rec edible p arities showstoppers =
+ let rec aux f showstoppers tms = function
+   | [] -> showstoppers
    | x::xs when List.exists (fun y -> hd_of x = Some y) showstoppers ->
       (* se la testa di x e' uno show-stopper *)
       let new_showstoppers = sort_uniq (showstoppers @ free_vars (x :> nf)) in
       (* aggiungi tutte le variabili libere di x *)
       if List.length showstoppers <> List.length new_showstoppers then
-       aux new_showstoppers ps
+       aux f new_showstoppers tms tms
       else
-       aux showstoppers xs
+       aux f showstoppers tms xs
    | x::xs ->
       match hd_of x with
-         None -> aux showstoppers xs
+         None -> aux f showstoppers tms xs
        | Some h ->
           try
-           dangerous arities showstoppers (x : i_n_var :> nf_nob) ;
-           aux showstoppers xs
+           f showstoppers (x :> nf_nob) ;
+           aux f showstoppers tms xs
           with
            Dangerous ->
-            aux (sort_uniq (h::showstoppers)) ps
+            aux f (sort_uniq (h::showstoppers)) tms tms
   in
-    let showstoppers = sort_uniq (aux showstoppers ps) in
-    let dangerous_conv =
-     List.map (dangerous_conv p arities showstoppers) (conv :> nf_nob list) 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 showstoppers = sort_uniq (aux (dangerous arities) showstoppers p.ps p.ps) in
+   let dangerous_conv = sort_uniq (aux (dangerous_conv p arities) showstoppers p.conv p.conv) in
 
-    let showstoppers' = showstoppers @ List.concat dangerous_conv in
-    let showstoppers' = sort_uniq (match div with
+    let showstoppers' = showstoppers @ dangerous_conv in
+    let showstoppers' = sort_uniq (match p.div with
      | None -> showstoppers'
      | Some div ->
        if List.exists ((=) (hd_of_i_var div)) showstoppers'
        then showstoppers' @ free_vars (div :> nf) else showstoppers') in
-    if showstoppers <> showstoppers' then edible p arities showstoppers' else showstoppers', dangerous_conv
+    if showstoppers <> showstoppers' then edible p arities showstoppers' else showstoppers'
 ;;
 
 let precompute_edible_data {ps; div} xs =
@@ -436,8 +432,8 @@ let critical_showstoppers p =
   let showstoppers_eat = List.filter
     (fun x -> not (List.mem x showstoppers_step))
     showstoppers_eat in
-  List.iter (fun v -> prerr_endline ("DANGEROUS STEP: " ^ (string_of_var p.var_names) v)) showstoppers_step;
-  List.iter (fun v -> prerr_endline ("DANGEROUS EAT: " ^ (string_of_var p.var_names) v)) showstoppers_eat;
+prerr_endline ("DANGEROUS STEP: " ^ String.concat " " (List.map (string_of_var p.var_names) showstoppers_step));
+prerr_endline ("DANGEROUS EAT: " ^ String.concat " " (List.map (string_of_var p.var_names) showstoppers_eat));
   p, showstoppers_step, showstoppers_eat
   ;;
 
@@ -446,15 +442,15 @@ 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 inedible, showstoppers_conv = edible p arities showstoppers in
+  let inedible = edible p arities showstoppers in
+  prerr_endline ("showstoppers (in eat)" ^ String.concat " " (List.map (string_of_var p.var_names) inedible));
   let l = List.filter (fun (_,hd,_) -> not (List.mem hd inedible)) arities in
-  let p =
-  List.fold_left (fun p (pos,hd,nargs) -> if pos = -1 then p else
-   let v = `N pos in
+  let new_sigma = List.map (fun (pos,hd,nargs) ->
+   let v = if pos = -1 then `Bottom else `N pos in
    let inst = make_lams v nargs in
 prerr_endline ("# [INST_IN_EAT] eating: " ^ string_of_var p.var_names hd ^ " := " ^ string_of_term p inst);
-   { p with sigma = p.sigma @ [hd,inst] }
-   ) p l in
+    hd,inst
+   ) l in
   (* to avoid applied numbers in safe positions that
      trigger assert failures subst_in_problem x inst p*)
  let ps =
@@ -464,32 +460,20 @@ prerr_endline ("# [INST_IN_EAT] eating: " ^ string_of_var p.var_names hd ^ " :=
     `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) inedible
-   then p
-   else
-    let n = match div with `I(_,args) -> Listx.length args | `Var _ -> 0 in
-    let x = hd_of_i_var div in
-    let inst = make_lams `Bottom n in
-    subst_in_problem x inst p in
- let dangerous_conv = showstoppers_conv in
+(*let dangerous_conv = showstoppers_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;
+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 ->
+   List.map (function t ->
     try
-     if s <> [] then t else (
      (match t with | `Var _ -> raise Not_found | _ -> ());
-     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
-     | Some h ->
-      prerr_endline ("FREEZING " ^ string_of_var p.var_names h);
-      convergent_dummy
-   ) (List.combine showstoppers_conv p.conv) 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)
+      | Some h -> prerr_endline ("FREEZING " ^ string_of_var p.var_names h));
+     convergent_dummy)
+   ) p.conv in
  List.iter
   (fun bs ->
     bs :=
@@ -502,6 +486,9 @@ List.iter (fun l -> prerr_endline (String.concat " " (List.map (string_of_var p.
   ) p.deltas ;
  let old_conv = p.conv in
  let p = { p with ps; conv } in
+ (* In case (match x ... with ...) and we are eating x,
+    so we need to substitute *)
+ let p = List.fold_left (fun p (x,inst) -> subst_in_problem x inst p) p new_sigma in
  if l <> [] || old_conv <> conv
   then prerr_endline (string_of_problem "eat" p);
  if List.for_all (function `N _ -> true | _ -> false) ps && p.div = None then
@@ -593,15 +580,16 @@ let choose_step p =
 ;;
 
 let rec auto_eat p =
- prerr_endline "{{{{{{{{ Computing measure before auto_instantiate }}}}}}";
+(* prerr_endline "{{{{{{{{ Computing measure before auto_instantiate }}}}}}"; *)
  let m = problem_measure p in
  let x, arity_of = choose_step p in
  first arity_of p x (fun p j ->
   let p' = instantiate p x j in
+  prerr_endline (string_of_problem "after instantiate" p');
   match eat p' with
   | `Finished p -> p
   | `Continue p ->
-      prerr_endline "{{{{{{{{ Computing measure inafter auto_instantiate }}}}}}";
+(* prerr_endline "{{{{{{{{ Computing measure inafter auto_instantiate }}}}}}"; *)
       let delta = problem_measure p - m in
       if delta >= 0
        then