Optimizer: refactored according to its formal description

[helm.git] / components / acic_procedural / proceduralClassify.ml

diff --git a/components/acic_procedural/proceduralClassify.ml b/components/acic_procedural/proceduralClassify.ml
index d21c14601f5108502d27de3c34f1511e3b89c3ab..6c1e482c2ff4d86aee5ee01cb988e50ece825630 100644 (file)
--- a/components/acic_procedural/proceduralClassify.ml
+++ b/components/acic_procedural/proceduralClassify.ml
@@ -28,12 +28,14 @@ module D   = Deannotate
 module I   = CicInspect
 module PEH = ProofEngineHelpers
 
+type dependence = I.S.t * bool
+
 type conclusion = (int * int) option
 
 (* debugging ****************************************************************)
 
-let string_of_entry inverse =
-   if I.S.mem 0 inverse then "C" else
+let string_of_entry (inverse, b) =
+   if I.S.mem 0 inverse then begin if b then "CF" else "C" end else
    if I.S.is_empty inverse then "I" else "P"
 
 let to_string (classes, rc) =
@@ -53,25 +55,43 @@ let out_table b =
    
 (****************************************************************************)
 
-let id x = x
+let identity x = x
 
-let classify_conclusion = function
-   | _, C.Rel i                -> Some (i, 0)
-   | _, C.Appl (C.Rel i :: tl) -> Some (i, List.length tl)
-   | _                         -> None
+let fst3 (x, _, _) = x
 
+let classify_conclusion vs = 
+   let rec get_argsno = function
+      | c, C.Appl (t :: vs) -> 
+         let hd, argsno = get_argsno (c, t) in 
+         hd, argsno + List.length vs
+      | _, t                -> t, 0
+   in
+   let inside i = i > 1 && i <= List.length vs in
+   match vs with
+      | v0 :: v1 :: _ ->
+         let hd0, argsno0 = get_argsno v0 in
+        let hd1, argsno1 = get_argsno v1 in
+        begin match hd0, hd1 with
+           | C.Rel i, C.MutInd _ when inside i -> Some (i, argsno0)
+           | _                                 -> None
+        end
+      | _             -> None
+ 
 let classify c t =
 try   
    let vs, h = PEH.split_with_whd (c, t) in
-   let rc = classify_conclusion (List.hd vs) in
-   let map (b, h) (_, v) = (I.get_rels_from_premise h v, I.S.empty) :: b, succ h in
+   let rc = classify_conclusion vs in
+   let map (b, h) (c, v) = 
+      let _, argsno = PEH.split_with_whd (c, v) in
+      (I.get_rels_from_premise h v, I.S.empty, argsno > 0) :: b, succ h
+   in
    let l, h = List.fold_left map ([], 0) vs in
    let b = Array.of_list (List.rev l) in
    let mk_closure b h =
-      let map j = if j < h then I.S.union (fst b.(j)) else id in 
+      let map j = if j < h then I.S.union (fst3 b.(j)) else identity in 
       for i = pred h downto 0 do
-         let direct, unused = b.(i) in
-        b.(i) <- I.S.fold map direct direct, unused 
+         let direct, unused, fa = b.(i) in
+        b.(i) <- I.S.fold map direct direct, unused, fa 
       done; b
    in
    let b = mk_closure b h in
@@ -79,13 +99,14 @@ try
       if I.S.is_empty direct then () else
       let j = I.S.choose direct in
       if j < h then
-         let unused, inverse = b.(j) in 
-         b.(j) <- unused, I.S.add i inverse
+         let unused, inverse, fa = b.(j) in 
+         b.(j) <- unused, I.S.add i inverse, fa
        else ();
        mk_inverse i (I.S.remove j direct)
    in
-   let map i (direct, _) = mk_inverse i direct in
+   let map i (direct, _, _) = mk_inverse i direct in
    Array.iteri map b;
 (*   out_table b; *)
-   List.rev_map snd (List.tl (Array.to_list b)), rc
+   let extract (x, y, z) = y, z in
+   List.rev_map extract (List.tl (Array.to_list b)), rc
 with Invalid_argument _ -> failwith "Classify.classify"