[Mesa-dev] [PATCH] i965: Add an option to not generate the SIMD8 fragment shader

[Matt Turner]

On Fri, Jul 11, 2014 at 11:26 AM, Kristian Høgsberg <krh at bitplanet.net> wrote:
> For now, this can only be triggered with a new 'no8' INTEL_DEBUG option
>
> Signed-off-by: Kristian Høgsberg <krh at bitplanet.net>
> ---
>  src/mesa/drivers/dri/i965/brw_context.h   |  2 ++
>  src/mesa/drivers/dri/i965/brw_fs.cpp      | 14 ++++++++++++--
>  src/mesa/drivers/dri/i965/gen7_wm_state.c |  4 ++--
>  src/mesa/drivers/dri/i965/gen8_ps_state.c |  4 ++--
>  src/mesa/drivers/dri/i965/intel_debug.c   |  1 +
>  src/mesa/drivers/dri/i965/intel_debug.h   |  1 +
>  6 files changed, 20 insertions(+), 6 deletions(-)
>
> diff --git a/src/mesa/drivers/dri/i965/brw_context.h b/src/mesa/drivers/dri/i965/brw_context.h
> index 2943a20..11cea04 100644
> --- a/src/mesa/drivers/dri/i965/brw_context.h
> +++ b/src/mesa/drivers/dri/i965/brw_context.h
> @@ -340,6 +340,7 @@ struct brw_wm_prog_data {
>        /** @} */
>     } binding_table;
>
> +   bool no_8;
>     bool dual_src_blend;
>     bool uses_pos_offset;
>     bool uses_omask;
> @@ -1039,6 +1040,7 @@ struct brw_context
>     bool has_compr4;
>     bool has_negative_rhw_bug;
>     bool has_pln;
> +   bool no_simd8;

I don't think you need this? These bools are for device-specific features.

>
>     /**
>      * Some versions of Gen hardware don't do centroid interpolation correctly
> diff --git a/src/mesa/drivers/dri/i965/brw_fs.cpp b/src/mesa/drivers/dri/i965/brw_fs.cpp
> index a3ad375..f018d94 100644
> --- a/src/mesa/drivers/dri/i965/brw_fs.cpp
> +++ b/src/mesa/drivers/dri/i965/brw_fs.cpp
> @@ -3258,15 +3258,25 @@ brw_wm_fs_emit(struct brw_context *brw,
>        }
>     }
>
> +   exec_list *simd8_instructions;
> +   int no_simd8 = (INTEL_DEBUG & DEBUG_NO8) || brw->no_simd8;
> +   if (no_simd8 && simd16_instructions) {

... it's only used here.