[Mesa-stable] [Mesa-dev] [PATCH] nir: copy front interpolation when creating fake back color input

[Ilia Mirkin]

I wouldn't object to it being in stable, but it's also not
super-important. It does fix some piglits for freedreno though. (I
don't think vc4 exposes GL 3.0, so the problematic condition can't
happen there.)

On Mon, Jul 10, 2017 at 1:30 PM, Andres Gomez <agomez at igalia.com> wrote:
> Ilia, would we want this patch in -stable ?
>
> On Fri, 2017-07-07 at 20:34 -0400, Ilia Mirkin wrote:
>> Fixes a bunch of gl_BackColor interpolation tests that had explicit
>> interpolation specified on the fragment shader gl_Color.
>>
>> Signed-off-by: Ilia Mirkin <imirkin at alum.mit.edu>
>> ---
>>  src/compiler/nir/nir_lower_two_sided_color.c | 8 ++++++--
>>  1 file changed, 6 insertions(+), 2 deletions(-)
>>
>> diff --git a/src/compiler/nir/nir_lower_two_sided_color.c b/src/compiler/nir/nir_lower_two_sided_color.c
>> index 7d1a3bd236d..90da1013ec8 100644
>> --- a/src/compiler/nir/nir_lower_two_sided_color.c
>> +++ b/src/compiler/nir/nir_lower_two_sided_color.c
>> @@ -46,7 +46,8 @@ typedef struct {
>>   */
>>
>>  static nir_variable *
>> -create_input(nir_shader *shader, unsigned drvloc, gl_varying_slot slot)
>> +create_input(nir_shader *shader, unsigned drvloc, gl_varying_slot slot,
>> +             enum glsl_interp_mode interpolation)
>>  {
>>     nir_variable *var = rzalloc(shader, nir_variable);
>>
>> @@ -56,6 +57,7 @@ create_input(nir_shader *shader, unsigned drvloc, gl_varying_slot slot)
>>     var->name = ralloc_asprintf(var, "in_%d", drvloc);
>>     var->data.index = 0;
>>     var->data.location = slot;
>> +   var->data.interpolation = interpolation;
>>
>>     exec_list_push_tail(&shader->inputs, &var->node);
>>
>> @@ -116,7 +118,9 @@ setup_inputs(lower_2side_state *state)
>>        else
>>           slot = VARYING_SLOT_BFC1;
>>
>> -      state->colors[i].back = create_input(state->shader, ++maxloc, slot);
>> +      state->colors[i].back = create_input(
>> +            state->shader, ++maxloc, slot,
>> +            state->colors[i].front->data.interpolation);
>>     }
>>
>>     return 0;
> --
> Br,
>
> Andres