st/mesa: redefine mapping from VARYING_SLOT_TEXi/PNTC/VARi to TGSI GENERIC[i]

Generic varyings in TGSI were based on the value of VARYING_SLOT_TEX0, so VAR0
was always GENERIC[22] (with tessellation patches). Some drivers might not
be able to cope with that.

This commit defines a proper mapping, so that PNTC is GENERIC[8] and VAR0 is
GENERIC[9].

Reviewed-by: Brian Paul <[email protected]>

3 files changed, 52 insertions, 22 deletions

diff --git a/src/mesa/state_tracker/st_atom_rasterizer.c b/src/mesa/state_tracker/st_atom_rasterizer.c
index 71b7f1bd9a0..a2285383e7d 100644
--- a/src/mesa/state_tracker/st_atom_rasterizer.c
+++ b/src/mesa/state_tracker/st_atom_rasterizer.c
@@ -33,6 +33,7 @@
 #include "main/macros.h"
 #include "st_context.h"
 #include "st_atom.h"
+#include "st_program.h"
 #include "pipe/p_context.h"
 #include "pipe/p_defines.h"
 #include "cso_cache/cso_context.h"
@@ -174,7 +175,7 @@ static void update_raster_state( struct st_context *st )
       if (!st->needs_texcoord_semantic &&
           fragProg->Base.InputsRead & VARYING_BIT_PNTC) {
          raster->sprite_coord_enable |=
-            1 << (VARYING_SLOT_PNTC - VARYING_SLOT_TEX0);
+            1 << st_get_generic_varying_index(st, VARYING_SLOT_PNTC);
       }
 
       raster->point_quad_rasterization = 1;
diff --git a/src/mesa/state_tracker/st_program.c b/src/mesa/state_tracker/st_program.c
index fbf8930cb8b..926086bf898 100644
--- a/src/mesa/state_tracker/st_program.c
+++ b/src/mesa/state_tracker/st_program.c
@@ -275,17 +275,18 @@ st_prepare_vertex_program(struct gl_context *ctx,
          case VARYING_SLOT_TEX5:
          case VARYING_SLOT_TEX6:
          case VARYING_SLOT_TEX7:
-            stvp->output_semantic_name[slot] = st->needs_texcoord_semantic ?
-               TGSI_SEMANTIC_TEXCOORD : TGSI_SEMANTIC_GENERIC;
-            stvp->output_semantic_index[slot] = attr - VARYING_SLOT_TEX0;
-            break;
-
+            if (st->needs_texcoord_semantic) {
+               stvp->output_semantic_name[slot] = TGSI_SEMANTIC_TEXCOORD;
+               stvp->output_semantic_index[slot] = attr - VARYING_SLOT_TEX0;
+               break;
+            }
+            /* fall through */
          case VARYING_SLOT_VAR0:
          default:
             assert(attr < VARYING_SLOT_MAX);
             stvp->output_semantic_name[slot] = TGSI_SEMANTIC_GENERIC;
-            stvp->output_semantic_index[slot] = st->needs_texcoord_semantic ?
-               (attr - VARYING_SLOT_VAR0) : (attr - VARYING_SLOT_TEX0);
+            stvp->output_semantic_index[slot] =
+               st_get_generic_varying_index(st, attr);
             break;
          }
       }
@@ -655,9 +656,8 @@ st_translate_fragment_program(struct st_context *st,
              * the user varyings on VAR0.  Otherwise, we use TEX0 as base index.
              */
             assert(attr >= VARYING_SLOT_TEX0);
-            input_semantic_index[slot] = st->needs_texcoord_semantic ?
-               (attr - VARYING_SLOT_VAR0) : (attr - VARYING_SLOT_TEX0);
             input_semantic_name[slot] = TGSI_SEMANTIC_GENERIC;
+            input_semantic_index[slot] = st_get_generic_varying_index(st, attr);
             if (attr == VARYING_SLOT_PNTC)
                interpMode[slot] = TGSI_INTERPOLATE_LINEAR;
             else
@@ -974,16 +974,18 @@ st_translate_geometry_program(struct st_context *st,
          case VARYING_SLOT_TEX5:
          case VARYING_SLOT_TEX6:
          case VARYING_SLOT_TEX7:
-            stgp->input_semantic_name[slot] = st->needs_texcoord_semantic ?
-               TGSI_SEMANTIC_TEXCOORD : TGSI_SEMANTIC_GENERIC;
-            stgp->input_semantic_index[slot] = (attr - VARYING_SLOT_TEX0);
-            break;
+            if (st->needs_texcoord_semantic) {
+               stgp->input_semantic_name[slot] = TGSI_SEMANTIC_TEXCOORD;
+               stgp->input_semantic_index[slot] = attr - VARYING_SLOT_TEX0;
+               break;
+            }
+            /* fall through */
          case VARYING_SLOT_VAR0:
          default:
             assert(attr >= VARYING_SLOT_VAR0 && attr < VARYING_SLOT_MAX);
             stgp->input_semantic_name[slot] = TGSI_SEMANTIC_GENERIC;
-            stgp->input_semantic_index[slot] = st->needs_texcoord_semantic ?
-               (attr - VARYING_SLOT_VAR0) : (attr - VARYING_SLOT_TEX0);
+            stgp->input_semantic_index[slot] =
+               st_get_generic_varying_index(st, attr);
          break;
          }
       }
@@ -1069,17 +1071,19 @@ st_translate_geometry_program(struct st_context *st,
          case VARYING_SLOT_TEX5:
          case VARYING_SLOT_TEX6:
          case VARYING_SLOT_TEX7:
-            gs_output_semantic_name[slot] = st->needs_texcoord_semantic ?
-               TGSI_SEMANTIC_TEXCOORD : TGSI_SEMANTIC_GENERIC;
-            gs_output_semantic_index[slot] = (attr - VARYING_SLOT_TEX0);
-            break;
+            if (st->needs_texcoord_semantic) {
+               gs_output_semantic_name[slot] = TGSI_SEMANTIC_TEXCOORD;
+               gs_output_semantic_index[slot] = attr - VARYING_SLOT_TEX0;
+               break;
+            }
+            /* fall through */
          case VARYING_SLOT_VAR0:
          default:
             assert(slot < Elements(gs_output_semantic_name));
             assert(attr >= VARYING_SLOT_VAR0);
             gs_output_semantic_name[slot] = TGSI_SEMANTIC_GENERIC;
-            gs_output_semantic_index[slot] = st->needs_texcoord_semantic ?
-               (attr - VARYING_SLOT_VAR0) : (attr - VARYING_SLOT_TEX0);
+            gs_output_semantic_index[slot] =
+               st_get_generic_varying_index(st, attr);
          break;
          }
       }
diff --git a/src/mesa/state_tracker/st_program.h b/src/mesa/state_tracker/st_program.h
index 9a5b6a847a5..cf1b40a55fc 100644
--- a/src/mesa/state_tracker/st_program.h
+++ b/src/mesa/state_tracker/st_program.h
@@ -270,6 +270,31 @@ st_reference_fragprog(struct st_context *st,
                            (struct gl_program *) prog);
 }
 
+/**
+ * This defines mapping from Mesa VARYING_SLOTs to TGSI GENERIC slots.
+ */
+static INLINE unsigned
+st_get_generic_varying_index(struct st_context *st, GLuint attr)
+{
+   if (attr >= VARYING_SLOT_VAR0) {
+      if (st->needs_texcoord_semantic)
+         return attr - VARYING_SLOT_VAR0;
+      else
+         return 9 + (attr - VARYING_SLOT_VAR0);
+   }
+   if (attr == VARYING_SLOT_PNTC) {
+      assert(!st->needs_texcoord_semantic);
+      return 8;
+   }
+   if (attr >= VARYING_SLOT_TEX0 && attr <= VARYING_SLOT_TEX7) {
+      assert(!st->needs_texcoord_semantic);
+      return attr - VARYING_SLOT_TEX0;
+   }
+
+   assert(0);
+   return 0;
+}
+
 
 extern struct st_vp_variant *
 st_get_vp_variant(struct st_context *st,