[Mesa-dev] [PATCH 1/3] gallium: add explicit return type to texture opcodes

[Marek Olšák]

On Mon, Aug 22, 2016 at 10:18 PM, Dave Airlie <airlied at gmail.com> wrote:
> On 23 August 2016 at 06:14, Marek Olšák <maraeo at gmail.com> wrote:
>> On Mon, Aug 22, 2016 at 7:05 PM, Brian Paul <brianp at vmware.com> wrote:
>>> On 08/22/2016 08:38 AM, Marek Olšák wrote:
>>>>
>>>> From: Marek Olšák <marek.olsak at amd.com>
>>>>
>>>> Sampler view declarations have return types, but that doesn't work with
>>>> variable indexing (e.g. SAMP[-1+i]).
>>>>
>>>> Adding the return type to the instruction is simpler.
>>>>
>>>> All sampler view declaration flags might have to be removed since variable
>>>> indexing makes them inaccessible.
>>>
>>>
>>> Do you want to get rid of sampler view declarations entirely?
>>
>> No, they have their place and I think the sampler view declarations
>> should stay, but the flags that are attached to them are basically
>> inaccessible with variable indexing. Since I have no reason to add
>> array support for sampler view declarations (unlike IN,OUT,TEMP, where
>> we needed array support due to other reasons), I prefer moving the
>> flags to instructions.
>
> It should be illegal in all APIs I thought to do mixed arrays.
>
> So if you have 1+x, then the bits on 1 should be the same as the
> bits on all the other sampler views in the array (even though there is
> no array).
>
> Is there a real world problem being solved?

No, it's just for TGSI robustness (not to be confused with GL robustness).

Marek