Global Instance valid_rnd_NA : Valid_rnd (Znearest (Zle_bool 0)) := valid_rnd_N _.

Theorem generic_inclusion : forall e, (fexp2 e <= fexp1 e)%Z -> forall x, (bpow (e - 1) <= Rabs x <= bpow e)%R -> generic_format fexp1 x -> generic_format fexp2 x.