[Mesa-dev] [PATCH 04/11] glsl: Pack integer and double varyings as flat even if interpolation mode is none

[Timothy Arceri]

On Tue, 2016-06-14 at 19:01 -0700, Ian Romanick wrote:
> From: Ian Romanick <ian.d.romanick at intel.com>
> 
> Signed-off-by: Ian Romanick <ian.d.romanick at intel.com>
> Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=96358
> Cc: "12.0" <mesa-stable at lists.freedesktop.org>
> Cc: Gregory Hainaut <gregory.hainaut at gmail.com>
> Cc: Ilia Mirkin <imirkin at alum.mit.edu>
> ---

I guess we might also want to
update varying_matches::compute_packing_class() to make the most of
this.


>  src/compiler/glsl/lower_packed_varyings.cpp | 13 ++++++++-----
>  1 file changed, 8 insertions(+), 5 deletions(-)
> 
> diff --git a/src/compiler/glsl/lower_packed_varyings.cpp
> b/src/compiler/glsl/lower_packed_varyings.cpp
> index 130b8f6..ae36c1c 100644
> --- a/src/compiler/glsl/lower_packed_varyings.cpp
> +++ b/src/compiler/glsl/lower_packed_varyings.cpp
> @@ -273,11 +273,11 @@ lower_packed_varyings_visitor::run(struct
> gl_shader *shader)
>           continue;
>  
>        /* This lowering pass is only capable of packing floats and
> ints
> -       * together when their interpolation mode is
> "flat".  Therefore, to be
> -       * safe, caller should ensure that integral varyings always
> use flat
> -       * interpolation, even when this is not required by GLSL.
> +       * together when their interpolation mode is "flat".  Treat
> integers as
> +       * being flat when the interpolation mode is none.
>         */
>        assert(var->data.interpolation == INTERP_QUALIFIER_FLAT ||
> +             var->data.interpolation == INTERP_QUALIFIER_NONE ||
>               !var->type->contains_integer());
>  
>        /* Clone the variable for program resource list before
> @@ -607,7 +607,9 @@
> lower_packed_varyings_visitor::get_packed_varying_deref(
>     if (this->packed_varyings[slot] == NULL) {
>        char *packed_name = ralloc_asprintf(this->mem_ctx,
> "packed:%s", name);
>        const glsl_type *packed_type;
> -      if (unpacked_var->data.interpolation == INTERP_QUALIFIER_FLAT)
> +      if (unpacked_var->data.interpolation == INTERP_QUALIFIER_FLAT
> ||
> +          unpacked_var->type->contains_integer() ||
> +          unpacked_var->type->contains_double())
>           packed_type = glsl_type::ivec4_type;
>        else
>           packed_type = glsl_type::vec4_type;
> @@ -627,7 +629,8 @@
> lower_packed_varyings_visitor::get_packed_varying_deref(
>        packed_var->data.centroid = unpacked_var->data.centroid;
>        packed_var->data.sample = unpacked_var->data.sample;
>        packed_var->data.patch = unpacked_var->data.patch;
> -      packed_var->data.interpolation = unpacked_var-
> >data.interpolation;
> +      packed_var->data.interpolation = packed_type ==
> glsl_type::ivec4_type
> +         ? unsigned(INTERP_QUALIFIER_FLAT) : unpacked_var-
> >data.interpolation;
>        packed_var->data.location = location;
>        packed_var->data.precision = unpacked_var->data.precision;
>        packed_var->data.always_active_io = unpacked_var-
> >data.always_active_io;