equal_ignoring_subkind etc

Author: mshinwell

middle_end/flambda2/kinds/flambda_kind.ml

@@ -563,4 +563,6 @@ module With_subkind = struct
       true
 
   let erase_subkind t = { t with subkind = Anything }
+
+  let equal_ignoring_subkind t1 t2 = equal (erase_subkind t1) (erase_subkind t2)
 end

middle_end/flambda2/kinds/flambda_kind.mli

@@ -207,4 +207,6 @@ module With_subkind : sig
   val erase_subkind : t -> t
 
   include Container_types.S with type t := t
+
+  val equal_ignoring_subkind : t -> t -> bool
 end

middle_end/flambda2/simplify/env/continuation_uses.ml

@@ -107,12 +107,10 @@ let get_arg_types_by_use_id_for_invariant_params arity l =
   List.fold_left
     (fun arg_maps t ->
       if not
-           (Misc.Stdlib.List.is_prefix ~equal:Flambda_kind.equal
-              (Flambda_arity.to_list arity
-              |> List.map Flambda_kind.With_subkind.kind)
-              ~of_:
-                (Flambda_arity.to_list t.arity
-                |> List.map Flambda_kind.With_subkind.kind))
+           (Misc.Stdlib.List.is_prefix
+              ~equal:Flambda_kind.With_subkind.equal_ignoring_subkind
+              (Flambda_arity.to_list arity)
+              ~of_:(Flambda_arity.to_list t.arity))
       then
         Misc.fatal_errorf
           "Arity of invariant params@ (%a) is not a prefix of the arity of the \