[Mesa-dev] ARB_arrays_of_arrays GLSL ES

[Jason Ekstrand]

On Thu, Jun 25, 2015 at 1:19 AM, Timothy Arceri <t_arceri at yahoo.com.au> wrote:
> On Wed, 2015-06-24 at 11:17 -0700, Jason Ekstrand wrote:
>> On Sat, Jun 20, 2015 at 5:32 AM, Timothy Arceri <
>> t_arceri at yahoo.com.au> wrote:
>> > Hi all,
>> >
>> > The restrictions in ES make the extension easier to implement so
>> > I thought I'd try get this stuff reviewed an committed before
>> > finishing
>> > up the full extension.
>> > The bits that I'm still working on for the desktop version are AoA
>> > inputs
>> > outputs, and interface blocks.
>> >
>> > The only thing I know is definatly missing in this series for ES is
>> > support for indirect indexing of samplers, but that didn't seem
>> > like
>> > something that should hold up the series.
>> >
>> > Once the SSBO series lands (with a patch that restricts unsized
>> > arrays)
>> > then all the AoA ES conformance tests will pass.
>> >
>> > There are already a bunch of piglit tests in git but I've just sent
>> > a
>> > series with all the patches still waiting review here:
>> > http://lists.freedesktop.org/archives/piglit/2015-June/016312.html
>> >
>> > I haven't made a patch marking this as done yet because currently
>> > the i965 backend takes a very long time trying to optimise some of
>> > the
>> > conformance tests. They still pass but they are taking 15-minutes+
>> > just
>> > to compile so this really needs to be sorted out first. If someone
>> > with
>> > more knowledge in this area than me wants to take a look at this I
>> > would
>> > be greatful for being pointed in the right direction.
>>
>> Can you try it with this patch:
>>
>> http://lists.freedesktop.org/archives/mesa-dev/2015-June/086011.html
>
> Hi Jason,
>
> I tried that patch it didn't seem to make any difference, then I
> noticed its for fs. The slowdown is currently happening in
> vec4_live_variables. I've also noticed other large slowdowns with some
> piglit tests I've been working on this time in the register allocate
> code.

I just sent an equivalent patch for vec4:

http://patchwork.freedesktop.org/patch/52801/

I would love to know if it helps something so that I can put a good
justification in the commit message beyond "the same as for FS".
--Jason

> Once I finish fixing up some bugs with my current patchset I'll start
> digging deeper, just thought since it's so noticeably slow it might be
> easy for someone with good knowledge of the backend to point out where
> I should start looking, or to say your doing this wrong.
>
> One thing the slow shaders have in common is the use of arrays of
> arrays in nested loops so maybe something funny is going on when they
> go through the optimisation paths, I haven't spent much time looking at
> any of these passes yet so its highly likely they don't work as
> expected for arrays of arrays.
>
> Thanks anyway,
> Tim
>
>
>>
>> > If useful the series is in the 'gles4' branch of the repo here:
>> > https://github.com/tarceri/Mesa_arrays_of_arrays.git
>> >
>> > Thanks,
>> > Tim
>> > _______________________________________________
>> > mesa-dev mailing list
>> > mesa-dev at lists.freedesktop.org
>> > http://lists.freedesktop.org/mailman/listinfo/mesa-dev