[Mesa-dev] [PATCH] [rfc] st/nir: handle components on fs outputs.

[Dave Airlie]

From: Dave Airlie <airlied at redhat.com>

fs outputs don't start above VARYING_SLOT_VAR0, but I assume
that is there for a reason, so make an exception for fragment
outputs.

This fixes with NIR:
tests/spec/arb_enhanced_layouts/execution/component-layout/fs-output.shader_test

Signed-off-by: Dave Airlie <airlied at redhat.com>
---
 src/mesa/state_tracker/st_glsl_to_nir.cpp | 16 ++++++++--------
 1 file changed, 8 insertions(+), 8 deletions(-)

diff --git a/src/mesa/state_tracker/st_glsl_to_nir.cpp b/src/mesa/state_tracker/st_glsl_to_nir.cpp
index 765c827d93..4e7d54e11d 100644
--- a/src/mesa/state_tracker/st_glsl_to_nir.cpp
+++ b/src/mesa/state_tracker/st_glsl_to_nir.cpp
@@ -123,13 +123,13 @@ st_nir_assign_vs_in_locations(struct gl_program *prog, nir_shader *nir)
 
 static void
 st_nir_assign_var_locations(struct exec_list *var_list, unsigned *size,
-                            gl_shader_stage stage)
+                            gl_shader_stage stage, bool outputs)
 {
    unsigned location = 0;
    unsigned assigned_locations[VARYING_SLOT_TESS_MAX];
    uint64_t processed_locs = 0;
    uint32_t processed_patch_locs = 0;
-
+   bool is_fs_output = outputs && (stage == MESA_SHADER_FRAGMENT);
    nir_foreach_variable(var, var_list) {
 
       const struct glsl_type *type = var->type;
@@ -159,7 +159,7 @@ st_nir_assign_var_locations(struct exec_list *var_list, unsigned *size,
       /* Because component packing allows varyings to share the same location
        * we may have already have processed this location.
        */
-      if (processed && var->data.location >= VARYING_SLOT_VAR0) {
+      if (processed && (var->data.location >= VARYING_SLOT_VAR0 || is_fs_output)) {
          var->data.driver_location = assigned_locations[var->data.location];
          *size += type_size(type);
          continue;
@@ -687,7 +687,7 @@ st_finalize_nir(struct st_context *st, struct gl_program *prog,
       sort_varyings(&nir->outputs);
       st_nir_assign_var_locations(&nir->outputs,
                                   &nir->num_outputs,
-                                  nir->info.stage);
+                                  nir->info.stage, true);
       st_nir_fixup_varying_slots(st, &nir->outputs);
    } else if (nir->info.stage == MESA_SHADER_GEOMETRY ||
               nir->info.stage == MESA_SHADER_TESS_CTRL ||
@@ -695,23 +695,23 @@ st_finalize_nir(struct st_context *st, struct gl_program *prog,
       sort_varyings(&nir->inputs);
       st_nir_assign_var_locations(&nir->inputs,
                                   &nir->num_inputs,
-                                  nir->info.stage);
+                                  nir->info.stage, false);
       st_nir_fixup_varying_slots(st, &nir->inputs);
 
       sort_varyings(&nir->outputs);
       st_nir_assign_var_locations(&nir->outputs,
                                   &nir->num_outputs,
-                                  nir->info.stage);
+                                  nir->info.stage, true);
       st_nir_fixup_varying_slots(st, &nir->outputs);
    } else if (nir->info.stage == MESA_SHADER_FRAGMENT) {
       sort_varyings(&nir->inputs);
       st_nir_assign_var_locations(&nir->inputs,
                                   &nir->num_inputs,
-                                  nir->info.stage);
+                                  nir->info.stage, false);
       st_nir_fixup_varying_slots(st, &nir->inputs);
       st_nir_assign_var_locations(&nir->outputs,
                                   &nir->num_outputs,
-                                  nir->info.stage);
+                                  nir->info.stage, true);
    } else if (nir->info.stage == MESA_SHADER_COMPUTE) {
        /* TODO? */
    } else {
-- 
2.14.3