[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Date: Thu, 1 Nov 2012 13:58:35 +0530
From: Sayantan Datta <std2048@...il.com>
To: john-dev@...ts.openwall.com
Subject: Re: DES bitslice sboxs for GPUs (not AMD)
Hi alain,
On Thu, Nov 1, 2012 at 9:41 AM, Alain Espinosa <alainesp@...il.com> wrote:
> The sboxs in src/nonstd.c contains ANDN instructions that are not
> available in GPUs (if i read and understood the documentation). Of
> course we can convert ANDN to a AND plus a NOT, but i guess there are
> optimized sboxs without ANDN.
>
I'm not sure but I don't think there are any other sboxes other than these
two for DES. If the GPUs don't have andn instruction then the compiler is
probably doing the same AND + NOT but that may not be using least number of
instructions. So optimizing might involve a lot of boolean manipulations.
Regards,
Sayantan
Content of type "text/html" skipped
Powered by blists - more mailing lists
Confused about mailing lists and their use?
Read about mailing lists on Wikipedia
and check out these
guidelines on proper formatting of your messages.
