[Mesa-dev] Summer of Code ideas (maybe just an idea wishlist?)

[Ilia Mirkin]

On Thu, Mar 26, 2015 at 8:50 PM, Rob Clark <robdclark at gmail.com> wrote:
> On Thu, Mar 26, 2015 at 3:10 PM, Ilia Mirkin <imirkin at alum.mit.edu> wrote:
>> On Thu, Mar 26, 2015 at 3:02 PM, Jason Ekstrand <jason at jlekstrand.net> wrote:
>>> On Thu, Mar 26, 2015 at 12:00 PM, Aditya Avinash
>>> <adityaavinash1 at gmail.com> wrote:
>>>> I mean, implementing fp64 on single precision systems.
>>>
>>> Ok, That makes more sense!  Having lowering passes for various FP64
>>> operations would be great.
>>
>> We should make sure that there are customers of such work. It only
>> makes sense to do this when everything else but FP64 are supported for
>> GL 4.0 (including tess). r600 (eg/ni) is an obvious customer, although
>> that may be easier to do in sb (I believe GlennK has been looking at
>> it, not sure how far he's gotten). Other than that... not sure. Could
>> be that Adreno A420 can do tess && has no native fp64 support, still
>> need to figure that out (hasn't been RE'd yet).
>
> fwiw, fp64 lowering is almost certainly useful for a3xx when we get to
> the point of doing compute..

Why does compute need fp64? Do the blob drivers expose the fp64 capability?

>
> (on that topic, TGSI or NIR support for clover would be kinda awesome
> to get compute going on some drivers other than radeon.. probably TGSI
> would be more immediately useful for more drivers, but not sure how
> much would need to be added to TGSI, and NIR seems to be more
> future-proof..)

Before the whole SPIR-V thing, I had been toying with the idea of
getting clover to spit out SPIR since llvm knew how to generate it.
Now that SPIR-V is out, I think that's a more natural target and TGSI
replacement. But all that is somewhat in the future. Curro tried to
get llvm to spit out TGSI, but ended up running into trouble... that
was a few years back.

  -ilia