linux-kernel - Re: [PATCH RFC 1/3] rust: add useful ops for u64

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <1597EDB7-D91B-4660-ADDC-D2252B26CB22@collabora.com>
Date: Wed, 19 Feb 2025 20:13:15 -0300
From: Daniel Almeida <daniel.almeida@...labora.com>
To: Dave Airlie <airlied@...il.com>
Cc: John Hubbard <jhubbard@...dia.com>,
 Alexandre Courbot <acourbot@...dia.com>,
 Timur Tabi <ttabi@...dia.com>,
 "dri-devel@...ts.freedesktop.org" <dri-devel@...ts.freedesktop.org>,
 "rust-for-linux@...r.kernel.org" <rust-for-linux@...r.kernel.org>,
 "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
 "nouveau@...ts.freedesktop.org" <nouveau@...ts.freedesktop.org>,
 "dakr@...nel.org" <dakr@...nel.org>,
 Ben Skeggs <bskeggs@...dia.com>
Subject: Re: [PATCH RFC 1/3] rust: add useful ops for u64



> On 19 Feb 2025, at 17:23, Dave Airlie <airlied@...il.com> wrote:
> 
> On Thu, 20 Feb 2025 at 06:22, John Hubbard <jhubbard@...dia.com> wrote:
>> 
>> On 2/19/25 4:51 AM, Alexandre Courbot wrote:
>>> Yes, that looks like the optimal way to do this actually. It also
>>> doesn't introduce any overhead as the destructuring was doing both
>>> high_half() and low_half() in sequence, so in some cases it might
>>> even be more efficient.
>>> 
>>> I'd just like to find a better naming. high() and low() might be enough?
>>> Or are there other suggestions?
>>> 
>> 
>> Maybe use "32" instead of "half":
>> 
>>     .high_32()  / .low_32()
>>     .upper_32() / .lower_32()
>> 
> 
> The C code currently does upper_32_bits and lower_32_bits, do we want
> to align or diverge here?
> 
> Dave.


My humble suggestion here is to use the same nomenclature. `upper_32_bits` and
`lower_32_bits` immediately and succinctly informs the reader of what is going on.

— Daniel