Definition singleoflongu (x: aval) :=
match x with
| L i => FS(Float32.of_longu i)
| _   => ntop1 x
end.

(* Specifications: *)
Lemma singleoflongu_sound:
forall v x w, vmatch v x -> Val.singleoflongu v = Some w -> vmatch w (singleoflongu x).