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

[Ian Romanick]

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>
---
 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;
-- 
2.5.5