On Tue, Nov 5, 2013 at 3:59 AM, Christoph Hertzberg <
chtz@xxxxxxxxxxxxxxxxxxxxxxxx> wrote:
>
> On 05.11.2013 04:50, Gael Guennebaud wrote:
>>
>> On Tue, Nov 5, 2013 at 2:51 AM, Benoit Jacob <
jacob.benoit.1@xxxxxxxxx>wrote:
>>
>>> Regarding AVX support, I'm just watching Eigen from the sidelines anymore,
>>> but I'll say this: the best thing that could happen to Eigen is broadening
>>> of its user base, so it would be great to see features like AVX being
>>> contributed by new/non-core contributors.
>>
>>
>>
>> there are already two starts which seems to be at about the same stage:
>> -
https://bitbucket.org/rpg/eigen-avx
>> -
https://bitbucket.org/smoustafa/eigen-avx
>
>
> I have just glanced over those forks (please correct me if I state something incorrect). It appears to me that the first merely implemented all the p***-functions, but has not done anything w.r.t to integration. The second appears to have "hacked in" (most likely losing ABI compatibility at some points) its integration into the Core and I would assume it is in a testable state (I can't check, since I don't have an AVX machine at hand).
>
Yes, the first one has just the p*** functions, but nothing has been integrated yet. I am not in a position to work on the avx branch in the near future. Feel free to take over my fork in case you want to work on it.
> Maybe someone could try out that fork and compare how computation-times are with it (just for basic operations). Perhaps even compare them with blaze -- I assume their bigger FLOPS are mostly due to AVX usage.
> I think just testing that does not require deep understanding of Eigen or AVX, so anyone interested in AVX is welcome to do so. If someone gets a benchmark running, it would also be nice to have it run on different architectures.
>
> For a clean integration of AVX, however, I think we indeed need to enhance/rethink the packet logic (e.g. introduce meta-packets where the size is specified by another template parameter). And that is unlikely doable without good internal knowledge.
>
> Do you happen to plan another Eigen-Meeting in the forseable future? This (as well as the _expression_-Evaluator) would be nice things which could be boosted at such an event.
>
> Christoph
>
>
>
>
> --
> ----------------------------------------------
> Dipl.-Inf., Dipl.-Math. Christoph Hertzberg
> Cartesium 0.049
> Universität Bremen
> Enrique-Schmidt-Straße 5
> 28359 Bremen
>
> Tel: +49 (421) 218-64252
> ----------------------------------------------
>
>
--
Rohit Garg
http://rpg-314.blogspot.com/
Graduate Student
Applied and Engineering Physics
Cornell University