(** Validity *)

Definition eventval_valid (ev: eventval) : Prop :=
  match ev with
  | EVint _ => True
  | EVlong _ => True
  | EVfloat _ => True
  | EVsingle _ => True
  | EVptr_global id ofs => Senv.public_symbol ge id = true
  end.Definition eventval_type (ev: eventval) : typ :=
  match ev with
  | EVint _ => Tint
  | EVlong _ => Tlong
  | EVfloat _ => Tfloat
  | EVsingle _ => Tsingle
  | EVptr_global id ofs => Tptr
  end.

Lemma eventval_match_receptive: forall ev1 ty v1 ev2, eventval_match ev1 ty v1 -> eventval_valid ev1 -> eventval_valid ev2 -> eventval_type ev1 = eventval_type ev2 -> exists v2, eventval_match ev2 ty v2.