[PATCH 1/3] rust: add `num` module with `PowerOfTwo` type

[Alexandre Courbot]

On Sat Aug 2, 2025 at 11:18 PM JST, Miguel Ojeda wrote:
> On Sat, Aug 2, 2025 at 4:02 PM Alexandre Courbot <acourbot at nvidia.com> wrote:
>>
>> Belated thanks for the suggestion; I have finally opened an ACP for
>> `last_set_bit` (and `first_set_bit` while we are at it):
>> https://github.com/rust-lang/libs-team/issues/631
>>
>> I am still entangled with how to best leverage `Alignment` for our
>> purposes, but think I am getting close to a v2 of this patchset.
>
> Thanks for filling that one -- linked now from our usual lists :)
>
>     https://github.com/Rust-for-Linux/linux/issues/514

We got some interesting feedback on the ACP already. I have been pointed
to `checked_ilog2` as an equivalent of `last_set_bit`, and it *does*
indeed work well as a replacement - with the caveat that the name is
not very natural to me (or anyone familiar with the C interface). Is
this something we can live with? If we decide to go with the existing
standard library method, how can we make sure that folks looking for an
equivalent of `fls` find `checked_ilog2`?