[Mesa-dev] Mesa (master): glsl: restrict consumer stage condition to modify interpolation type

[Michel Dänzer]

On 15.01.2016 16:55, Samuel Iglesias Gonsálvez wrote:
> On Fri, 2016-01-15 at 16:36 +0900, Michel Dänzer wrote:
>> On 15.01.2016 15:12, Samuel Iglesias =?UNKNOWN?Q?Gons=C3=A1lvez?=
>> wrote:
>>> Module: Mesa
>>> Branch: master
>>> Commit: 781d2787bc1cf975757a95d0d9324f734fa61c09
>>> URL:    http://cgit.freedesktop.org/mesa/mesa/commit/?id=781d2787bc
>>> 1cf975757a95d0d9324f734fa61c09
>>>
>>> Author: Samuel Iglesias Gonsálvez <siglesias at igalia.com>
>>> Date:   Tue Jan 12 15:36:56 2016 +0100
>>>
>>> glsl: restrict consumer stage condition to modify interpolation
>>> type
>>>
>>> Only modify interpolation type for integer-based varyings or when
>>> the
>>> consumer is known and different than fragment shader.
>>>
>>> If we are linking separate shader programs and the consumer is
>>> unknown,
>>> the consumer could be added later and be a fragment shader. If we
>>> modify the interpolation type in this case, we could read wrong
>>> values in the fragment shader inputs, as shown in bug 93320.
>>
>> This change broke 4 GL_ARB_gpu_shader_fp64 piglit tests for me with
>> radeonsi. Here's the assertion failure and backtrace for one of them:
>>
> 
> Mmm, OK. I am going to check what it is going on here. Maybe I need to
> restrict the consumer stage condition only to separate shader objects.
> 
> Once I have a patch, I will send it to you privately to test if it is
> fixed because I don't a machine with radeonsi driver.
> 
> Can you tell me which tests are failing? Perhaps I can reproduce this
> issue with llvmpipe.

Yes, I can reproduce the problem with llvmpipe. The failing tests are:

spec at arb_gpu_shader_fp64@execution at arb_gpu_shader_fp64-double-gettransformfeedbackvarying
spec at arb_gpu_shader_fp64@execution at arb_gpu_shader_fp64-tf-interleaved
spec at arb_gpu_shader_fp64@execution at arb_gpu_shader_fp64-tf-interleaved-aligned
spec at arb_gpu_shader_fp64@execution at arb_gpu_shader_fp64-tf-separate


-- 
Earthling Michel Dänzer               |               http://www.amd.com
Libre software enthusiast             |             Mesa and X developer