Section SHIFT_AMOUNT.
Variable l: Z.
Hypothesis l_range: 0 <= l < 32.
Variable N: int.
Hypothesis N_eq: Int.unsigned N = two_p l.
Remark mk_amount_range:
forall n, Int.ltu (Int.zero_ext l n) N = true.
Remark mk_amount_eq:
forall n, Int.ltu n N = true -> Int.zero_ext l n = n.
End SHIFT_AMOUNT.
Program Definition mk_amount32 (n: int): amount32 :=
{| a32_amount := Int.zero_ext 5 n |}.
Next Obligation.
apply mk_amount_range. omega. reflexivity.
Qed.

Lemma mk_amount32_eq: forall n,
Int.ltu n Int.iwordsize = true -> a32_amount (mk_amount32 n) = n.