(** The chunk that is appropriate to store and reload a value of
  the given type, without losing information. *)

Definition chunk_of_type (ty: typ) :=
  match ty with
  | Tint => Mint32
  | Tfloat => Mfloat64
  | Tlong => Mint64
  | Tsingle => Mfloat32
  | Tany32 => Many32
  | Tany64 => Many64
  end.

Lemma chunk_of_Tptr: chunk_of_type Tptr = Mptr.