(** Same, for 64-bit integers *)

Lemma divls_mul_params_sound:
forall d m p,
divls_mul_params d = Some(p, m) ->
0 <= m < Int64.modulus /\ 0 <= p < 64 /\
forall n,
Int64.min_signed <= n <= Int64.max_signed ->
Z.quot n d = Z.div (m * n) (two_p (64 + p)) + (if zlt n 0 then 1 else 0).