[Mesa-dev] [PATCH 4/6] glsl: mark xfb inputs as always_active_io

[Timothy Arceri]

On 10/10/17 10:02, Eric Anholt wrote:
> Timothy Arceri <tarceri at itsqueeze.com> writes:
> 
>> On 10/10/17 09:31, Eric Anholt wrote:
>>> Timothy Arceri <tarceri at itsqueeze.com> writes:
>>>
>>>> We won't split varyings marked as always active because there
>>>> is no point in doing so. This means we need to mark both
>>>> sides of the interface as always active otherwise we will have
>>>> a mismatch and start removing things we shouldn't.
>>>
>>> Is this just needed because the next patch only updates a single bit in
>>> the read/write arrays for multi-channel variables?  Or is there
>>> something else?
>>
>> We want to keep both sides the same. We don't want to have:
>>
>> vec4 on one side and float * 4 on the other. We might be able to handle
>> it but just for the simple readability of NIR dumps I don't think we
>> should do it. Thoughts?
> 
> Having them mix-and-matched seems OK to me, though I guess I can imagine
> similar issues popping up in other linking passes.
> 
> Could you add a comment explaining the motivation here?
> 

Sure, will add a comment.