[Mesa-dev] [PATCH 07/53] intel/fs: Add explicit last_rt flag to fb writes orthogonal to eot.

[Matt Turner]

On Fri, May 25, 2018 at 12:14 PM, Jason Ekstrand <jason at jlekstrand.net> wrote:
> On Fri, May 25, 2018 at 11:27 AM, Matt Turner <mattst88 at gmail.com> wrote:
>>
>> On Thu, May 24, 2018 at 2:55 PM, Jason Ekstrand <jason at jlekstrand.net>
>> wrote:
>> > From: Francisco Jerez <currojerez at riseup.net>
>>
>> I think some explanation is required. I'm guessing this is because you
>> have to write lo fragments out before high, but we should say that in
>> the commit message.
>
>
> How about this:
>
> When using multiple RT write messages to the same RT such as for dual-source
> blending or all RT writes in SIMD32, we have to set the "Last Render Target
> Select" bit on all write messages that target the last RT but only set EOT
> on the last RT write in the shader.  Special-casing for dual-source blend
> works today because that is the only case which requires multiple RT write
> messages per RT.  When we start doing SIMD32, this will become much more
> common so we add a dedicated bit for it.

Sounds good to me.

Reviewed-by: Matt Turner <mattst88 at gmail.com>