From 88711d38363280249571fed103d8dbe5ddaf4d7f Mon Sep 17 00:00:00 2001
From: Enrico Tassi <enrico.tassi@inria.fr>
Date: Mon, 14 Apr 2008 13:21:15 +0000
Subject: [PATCH] same_obj made more precise, fixed the order of the context
 for fixpoints body, cache of fix extended to the mutual case (properly)

---
 .../components/ng_kernel/oCic2NCic.ml         | 64 +++++++++++++------
 1 file changed, 46 insertions(+), 18 deletions(-)

diff --git a/helm/software/components/ng_kernel/oCic2NCic.ml b/helm/software/components/ng_kernel/oCic2NCic.ml
index 9751fa7bf..d66f45bd1 100644
--- a/helm/software/components/ng_kernel/oCic2NCic.ml
+++ b/helm/software/components/ng_kernel/oCic2NCic.ml
@@ -272,36 +272,64 @@ let get_fresh,reset_seed =
   (function () -> seed := 0)
 ;;
 
+exception NotSimilar 
+let alpha t1 t2 ref ref' =
+  let rec aux t1 t2 = match t1,t2 with
+    | NCic.Rel n, NCic.Rel m when n=m -> ()
+    | NCic.Appl l1, NCic.Appl l2 -> List.iter2 aux l1 l2
+    | NCic.Lambda (_,s1,t1), NCic.Lambda (_,s2,t2) 
+    | NCic.Prod (_,s1,t1), NCic.Prod (_,s2,t2) -> aux s1 s2; aux t1 t2
+    | NCic.LetIn (_,s1,ty1,t1), NCic.LetIn (_,s2,ty2,t2) -> 
+         aux s1 s2; aux ty1 ty2; aux t1 t2
+    | NCic.Const r1, 
+      NCic.Const r2 when NReference.eq r1 ref && NReference.eq r2 ref' -> ()
+    | NCic.Const r1, NCic.Const r2 when NReference.eq r1 r2 -> ()
+    | NCic.Meta _,NCic.Meta _ -> ()
+    | NCic.Implicit _,NCic.Implicit _ -> ()
+    | NCic.Sort x,NCic.Sort y when x=y -> ()
+    | NCic.Match (_,t1,t11,tl1), NCic.Match (_,t2,t22,tl2) -> 
+         aux t1 t2;aux t11 t22;List.iter2 aux tl1 tl2 
+    | _-> raise NotSimilar
+  in
+  try aux t1 t2; true  with NotSimilar -> false
+;;
+
 exception Found of NReference.reference;;
 let cache = Hashtbl.create 313;; 
-let same_obj =
+let same_obj ref ref' =
  function
-    (_,_,_,_,NCic.Fixpoint (_,(_,_,_,ty1,_)::_,_)),
-    (_,_,_,_,NCic.Fixpoint (_,(_,_,_,ty2,_)::_,_))
-     when ty1 = ty2 -> true
+  | (_,_,_,_,NCic.Fixpoint (_,l1,_)), (_,_,_,_,NCic.Fixpoint (_,l2,_))
+    when List.for_all2 (fun (_,_,_,ty1,bo1) (_,_,_,ty2,bo2) -> 
+       alpha ty1 ty2 ref ref' && alpha bo1 bo2 ref ref') l1 l2 ->
+     true
   | _ -> false
 ;;
 let find_in_cache name obj ref =
  try
   List.iter
    (function (ref',obj') ->
-     let recno =
+     let recno, fixno =
       match ref with
-         NReference.Ref (_,_,NReference.Fix (_,recno)) -> recno
+         NReference.Ref (_,_,NReference.Fix (fixno,recno)) -> recno,fixno
        | _ -> assert false in
-     let recno' =
+     let recno',fixno' =
       match ref' with
-         NReference.Ref (_,_,NReference.Fix (_,recno)) -> recno
+         NReference.Ref (_,_,NReference.Fix (fixno',recno)) -> recno,fixno'
        | _ -> assert false in
-     if recno = recno' && same_obj (obj,obj') then (
-(* prerr_endline "!!!!!!!!!!! CACHE HIT !!!!!!!!!!"; *)
-       raise (Found ref')
-);
+     if recno = recno' && fixno = fixno' && same_obj ref ref' (obj,obj') then (
+(*
+prerr_endline ("!!!!!!!!!!! CACHE HIT !!!!!!!!!!\n" ^
+NReference.string_of_reference ref ^ "\n" ^
+NReference.string_of_reference ref' ^ "\n"); 
+*)
+       raise (Found ref'));
+
 (*
 prerr_endline ("CACHE SAME NAME: " ^ NReference.string_of_reference ref ^ " <==> " ^ NReference.string_of_reference ref');
 *)
+
   ) (Hashtbl.find_all cache name);
-(* prerr_endline "<<< CACHE MISS >>>"; *)
+(*  prerr_endline "<<< CACHE MISS >>>";  *)
   begin
     match obj, ref with 
     | (_,_,_,_,NCic.Fixpoint (true,fl,_)) , NReference.Ref (x,y,NReference.Fix _) ->
@@ -341,8 +369,8 @@ let convert_term uri t =
             (fun (name,ty,_) (bctx, fixpoints, tys, idx) -> 
               let ty, fixpoints_ty = aux true octx ctx n_fix uri ty in
               let r = Ref.reference_of_ouri buri(Ref.CoFix idx) in
-              Fix (r,name,ty) :: bctx, fixpoints_ty @ fixpoints,ty::tys,idx+1)
-            fl ([], [], [], 0)
+              bctx @ [Fix (r,name,ty)], fixpoints_ty @ fixpoints,ty::tys,idx-1)
+            fl ([], [], [], List.length fl-1)
         in
         let bctx = bctx @ ctx in
         let n_fl = List.length fl in
@@ -386,8 +414,8 @@ let convert_term uri t =
               let r =  (* recno is dummy here, must be lifted by the ctx len *)
                 Ref.reference_of_ouri buri (Ref.Fix (idx,recno)) 
               in
-              Fix (r,name,ty) :: bctx, fixpoints_ty@fixpoints,ty::tys,idx+1)
-            fl ([], [], [], 0)
+              bctx @ [Fix (r,name,ty)], fixpoints_ty@fixpoints,ty::tys,idx-1)
+            fl ([], [], [], List.length fl-1)
         in
         let _, _, free_decls, _ = context_tassonomy (bad_bctx @ ctx) in
         let bctx = 
@@ -422,7 +450,7 @@ let convert_term uri t =
             NCic.Fixpoint (true, fl, (`Generated, `Definition)) in
         let r = Ref.reference_of_ouri buri (Ref.Fix (fixno,!rno_fixno)) in
         let obj,r =
-         let _,name,_,_,_ = List.hd fl in
+         let _,name,_,_,_ = List.nth fl fixno in
          match find_in_cache name obj r with
             Some r' -> [],r'
           | None -> [obj],r
-- 
2.39.2