[Mesa-dev] [PATCH] gallium/ttn: mark location specially in nir for color0-writes-all

[Rob Clark]

Connor, btw, how does glsl_to_nir handle this?

I guess at some point we want to try to align ttn w/ gtn (ie. cleanup
the whole nir with a tgsi accent thing)..

not that this would be the worst of the ttn vs gtn diff's in the
current state, so it is fine if there isn't a better way to do it
right now.. but I would like to start moving towards using nir
#define's for semantic names/indexes, etc, rather than tgsi or glsl
specific ones..  in the end the driver shouldn't have to care if the
nir came from tgsi/glsl/spirv/etc

BR,
-R


On Sat, Jun 27, 2015 at 5:38 PM, Ilia Mirkin <imirkin at alum.mit.edu> wrote:
> We need to distinguish a shader that has separate writes to each MRT
> from one which is supposed to write the data from MRT 0 to all the MRTs.
> In TGSI this is done with a property. NIR doesn't have that, so encode
> it as a funny location and decode on the other end.
>
> Signed-off-by: Ilia Mirkin <imirkin at alum.mit.edu>
> ---
>
> This fixes bin/fbo-drawbuffers-none gl_FragColor when I additionally
> initialize the "default" colors to a register other than r0.x -- as is
> this happens to work by luck.
>
> Also fix up vc4 to ignore this for now.
>
>  src/gallium/auxiliary/nir/tgsi_to_nir.c              | 7 ++++++-
>  src/gallium/drivers/freedreno/ir3/ir3_compiler_nir.c | 4 ++++
>  src/gallium/drivers/vc4/vc4_program.c                | 6 ++++++
>  3 files changed, 16 insertions(+), 1 deletion(-)
>
> diff --git a/src/gallium/auxiliary/nir/tgsi_to_nir.c b/src/gallium/auxiliary/nir/tgsi_to_nir.c
> index bf7eb2f..4130697 100644
> --- a/src/gallium/auxiliary/nir/tgsi_to_nir.c
> +++ b/src/gallium/auxiliary/nir/tgsi_to_nir.c
> @@ -253,7 +253,12 @@ ttn_emit_declaration(struct ttn_compile *c)
>              var->name = ralloc_asprintf(var, "out_%d", idx);
>
>              var->data.location = decl->Semantic.Name;
> -            var->data.index = decl->Semantic.Index;
> +            if (decl->Semantic.Name == TGSI_SEMANTIC_COLOR &&
> +                decl->Semantic.Index == 0 &&
> +                c->scan->properties[TGSI_PROPERTY_FS_COLOR0_WRITES_ALL_CBUFS])
> +               var->data.index = -1;
> +            else
> +               var->data.index = decl->Semantic.Index;
>
>              if (is_array) {
>                 unsigned j;
> diff --git a/src/gallium/drivers/freedreno/ir3/ir3_compiler_nir.c b/src/gallium/drivers/freedreno/ir3/ir3_compiler_nir.c
> index 3b36114..fa13c40 100644
> --- a/src/gallium/drivers/freedreno/ir3/ir3_compiler_nir.c
> +++ b/src/gallium/drivers/freedreno/ir3/ir3_compiler_nir.c
> @@ -2110,6 +2110,10 @@ setup_output(struct ir3_compile *ctx, nir_variable *out)
>                         so->writes_pos = true;
>                         break;
>                 case TGSI_SEMANTIC_COLOR:
> +                       if (semantic_index == -1) {
> +                               semantic_index = 0;
> +                               so->color0_mrt = 1;
> +                       }
>                         break;
>                 default:
>                         compile_error(ctx, "unknown FS semantic name: %s\n",
> diff --git a/src/gallium/drivers/vc4/vc4_program.c b/src/gallium/drivers/vc4/vc4_program.c
> index 2061631..728ecc6 100644
> --- a/src/gallium/drivers/vc4/vc4_program.c
> +++ b/src/gallium/drivers/vc4/vc4_program.c
> @@ -1783,6 +1783,12 @@ ntq_setup_outputs(struct vc4_compile *c)
>
>                  assert(array_len == 1);
>
> +                /* NIR hack to pass through
> +                 * TGSI_PROPERTY_FS_COLOR0_WRITES_ALL_CBUFS */
> +                if (semantic_name == TGSI_SEMANTIC_COLOR &&
> +                    semantic_index == -1)
> +                        semantic_index = 0;
> +
>                  for (int i = 0; i < 4; i++) {
>                          add_output(c,
>                                     loc + i,
> --
> 2.3.6
>
> _______________________________________________
> mesa-dev mailing list
> mesa-dev at lists.freedesktop.org
> http://lists.freedesktop.org/mailman/listinfo/mesa-dev