[Mesa-dev] [PATCH 3/7] nir: Add blend_const_color_rgba sysval

[Ian Romanick]

This commit is

Reviewed-by: Ian Romanick <ian.d.romanick at intel.com>

On 5/5/19 7:26 PM, Alyssa Rosenzweig wrote:
> This represents a float vec4 constant color, as passed to glBlendColor.
> While the existing 4 shader sysvals are retained to minimize code churn,
> a single vectorized intrinsic is required for efficient blending on
> vector architectures. (This may also apply to archictectures like
> Bifrost where ALU is scalar but load/store is vector; it largely depends
> on how blending is implemented per-driver.)
> 
> Signed-off-by: Alyssa Rosenzweig <alyssa at rosenzweig.io>
> Cc: Eric Anholt <eric at anholt.net>
> Cc: Kenneth Graunke <kenneth at whitecape.org>
> ---
>  src/compiler/nir/nir_intrinsics.py | 5 ++++-
>  1 file changed, 4 insertions(+), 1 deletion(-)
> 
> diff --git a/src/compiler/nir/nir_intrinsics.py b/src/compiler/nir/nir_intrinsics.py
> index 3a0470c2ca1..df459a3cdec 100644
> --- a/src/compiler/nir/nir_intrinsics.py
> +++ b/src/compiler/nir/nir_intrinsics.py
> @@ -568,11 +568,14 @@ system_value("viewport_z_offset", 1)
>  system_value("viewport_scale", 3)
>  system_value("viewport_offset", 3)
>  
> -# Blend constant color values.  Float values are clamped.#
> +# Blend constant color values.  Float values are clamped. Vectored versions are
> +# provided as well for driver convenience
> +
>  system_value("blend_const_color_r_float", 1)
>  system_value("blend_const_color_g_float", 1)
>  system_value("blend_const_color_b_float", 1)
>  system_value("blend_const_color_a_float", 1)
> +system_value("blend_const_color_rgba", 4)
>  system_value("blend_const_color_rgba8888_unorm", 1)
>  system_value("blend_const_color_aaaa8888_unorm", 1)