i965: Move Gen4-5 interpolation stuff to brw_wm_prog_data.

This fixes glxgears rendering, which had surprisingly been broken since
late October!  Specifically, commit 91d61fbf7c.

glxgears uses glShadeModel(GL_FLAT) when drawing the main portion of the
gears, then uses glShadeModel(GL_SMOOTH) for drawing the Gouraud-shaded
inner portion of the gears.  This results in the same fragment program
having two different state-dependent interpolation maps: one where
gl_Color is flat, and another where it's smooth.

The problem is that there's only one gen4_fragment_program, so it can't
store both.  Each FS compile would trash the last one.  But, the FS
compiles are cached, so the first one would store FLAT, and the second
would see a matching program in the cache and never bother to compile
one with SMOOTH.  (Clearing the program cache on every draw made it
render correctly.)

Instead, move it to brw_wm_prog_data, where we can keep a copy for
every specialization of the program.  The only downside is bloating
the structure a bit, but we can tighten that up a bit if we need to.
This also lets us kill gen4_fragment_program entirely!

Signed-off-by: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Timothy Arceri <timothy.arceri@collabora.com>

src/mesa/drivers/dri/i965/brw_clip.c

@@ -139,7 +139,7 @@ brw_upload_clip_prog(struct brw_context *brw)
                         _NEW_POLYGON |
                         _NEW_TRANSFORM,
                         BRW_NEW_BLORP |
-                        BRW_NEW_FRAGMENT_PROGRAM |
+                        BRW_NEW_FS_PROG_DATA |
                         BRW_NEW_REDUCED_PRIMITIVE |
                         BRW_NEW_VUE_MAP_GEOM_OUT))
       return;
@@ -149,15 +149,14 @@ brw_upload_clip_prog(struct brw_context *brw)
    /* Populate the key:
     */
 
-   const struct gl_program *fprog = brw->fragment_program;
-   if (fprog) {
-      assert(brw->gen < 6);
-      struct gen4_fragment_program *p = (struct gen4_fragment_program *) fprog;
-
-      /* BRW_NEW_FRAGMENT_PROGRAM */
-      key.contains_flat_varying = p->contains_flat_varying;
-      key.contains_noperspective_varying = p->contains_noperspective_varying;
-      key.interp_mode = p->interp_mode;
+   /* BRW_NEW_FS_PROG_DATA */
+   const struct brw_wm_prog_data *wm_prog_data =
+      brw_wm_prog_data(brw->wm.base.prog_data);
+   if (wm_prog_data) {
+      key.contains_flat_varying = wm_prog_data->contains_flat_varying;
+      key.contains_noperspective_varying =
+         wm_prog_data->contains_noperspective_varying;
+      key.interp_mode = wm_prog_data->interp_mode;
    }
 
    /* BRW_NEW_REDUCED_PRIMITIVE */

src/mesa/drivers/dri/i965/brw_clip.h

@@ -49,7 +49,7 @@ struct brw_clip_prog_key {
    GLbitfield64 attrs;
    bool contains_flat_varying;
    bool contains_noperspective_varying;
-   unsigned char *interp_mode;
+   const unsigned char *interp_mode;
    GLuint primitive:4;
    GLuint nr_userclip:4;
    GLuint pv_first:1;

src/mesa/drivers/dri/i965/brw_compiler.h

@@ -412,6 +412,9 @@ struct brw_wm_prog_data {
    bool has_side_effects;
    bool pulls_bary;
 
+   bool contains_flat_varying;
+   bool contains_noperspective_varying;
+
    /**
     * Mask of which interpolation modes are required by the fragment shader.
     * Used in hardware setup on gen6+.
@@ -424,6 +427,11 @@ struct brw_wm_prog_data {
     */
    uint32_t flat_inputs;
 
+   /* Mapping of VUE slots to interpolation modes.
+    * Used by the Gen4-5 clip/sf/wm stages.
+    */
+   unsigned char interp_mode[65]; /* BRW_VARYING_SLOT_COUNT */
+
    /**
     * Map from gl_varying_slot to the position within the FS setup data
     * payload where the varying's attribute vertex deltas should be delivered.
@@ -580,7 +588,7 @@ void brw_compute_tess_vue_map(struct brw_vue_map *const vue_map,
 /* brw_interpolation_map.c */
 void brw_setup_vue_interpolation(struct brw_vue_map *vue_map,
                                  struct nir_shader *nir,
-                                 struct gl_program *prog,
+                                 struct brw_wm_prog_data *prog_data,
                                  const struct gen_device_info *devinfo);
 
 enum shader_dispatch_mode {

src/mesa/drivers/dri/i965/brw_context.h

@@ -338,20 +338,6 @@ struct brw_program {
 };
 
 
-struct gen4_fragment_program {
-   struct brw_program base;
-
-   bool contains_flat_varying;
-   bool contains_noperspective_varying;
-
-   /*
-    * Mapping of varying slots to interpolation modes.
-    * Used Gen4/5 by the clip|sf|wm stages.
-    */
-   unsigned char interp_mode[BRW_VARYING_SLOT_COUNT];
-};
-
-
 /**
  * Bitmask indicating which fragment shader inputs represent varyings (and
  * hence have to be delivered to the fragment shader by the SF/SBE stage).

src/mesa/drivers/dri/i965/brw_fs.cpp

@@ -6382,10 +6382,17 @@ brw_compile_fs(const struct brw_compiler *compiler, void *log_data,
                unsigned *final_assembly_size,
                char **error_str)
 {
+   const struct gen_device_info *devinfo = compiler->devinfo;
+
    nir_shader *shader = nir_shader_clone(mem_ctx, src_shader);
    shader = brw_nir_apply_sampler_key(shader, compiler, &key->tex, true);
-   brw_nir_lower_fs_inputs(shader, vue_map, prog, compiler->devinfo, key);
+   brw_nir_lower_fs_inputs(shader, devinfo, key);
    brw_nir_lower_fs_outputs(shader);
+
+   if (devinfo->gen < 6) {
+      brw_setup_vue_interpolation(vue_map, shader, prog_data, devinfo);
+   }
+
    if (!key->multisample_fbo)
       NIR_PASS_V(shader, demote_sample_qualifiers);
    NIR_PASS_V(shader, move_interpolation_to_top);

src/mesa/drivers/dri/i965/brw_interpolation_map.c

@@ -37,20 +37,20 @@ static char const *get_qual_name(int mode)
 }
 
 static void
-gen4_frag_prog_set_interp_modes(struct gen4_fragment_program *prog,
+gen4_frag_prog_set_interp_modes(struct brw_wm_prog_data *prog_data,
                                 struct brw_vue_map *vue_map,
                                 unsigned location, unsigned slot_count,
                                 enum glsl_interp_mode interp)
 {
    for (unsigned k = 0; k < slot_count; k++) {
       unsigned slot = vue_map->varying_to_slot[location + k];
-      if (slot != -1 && prog->interp_mode[slot] == INTERP_MODE_NONE) {
-         prog->interp_mode[slot] = interp;
+      if (slot != -1 && prog_data->interp_mode[slot] == INTERP_MODE_NONE) {
+         prog_data->interp_mode[slot] = interp;
 
-         if (prog->interp_mode[slot] == INTERP_MODE_FLAT) {
-            prog->contains_flat_varying = true;
-         } else if (prog->interp_mode[slot] == INTERP_MODE_NOPERSPECTIVE) {
-            prog->contains_noperspective_varying = true;
+         if (prog_data->interp_mode[slot] == INTERP_MODE_FLAT) {
+            prog_data->contains_flat_varying = true;
+         } else if (prog_data->interp_mode[slot] == INTERP_MODE_NOPERSPECTIVE) {
+            prog_data->contains_noperspective_varying = true;
          }
       }
    }
@@ -59,13 +59,11 @@ gen4_frag_prog_set_interp_modes(struct gen4_fragment_program *prog,
 /* Set up interpolation modes for every element in the VUE */
 void
 brw_setup_vue_interpolation(struct brw_vue_map *vue_map, nir_shader *nir,
-                            struct gl_program *prog,
+                            struct brw_wm_prog_data *prog_data,
                             const struct gen_device_info *devinfo)
 {
-   struct gen4_fragment_program *fprog = (struct gen4_fragment_program *) prog;
-
    /* Initialise interp_mode. INTERP_MODE_NONE == 0 */
-   memset(fprog->interp_mode, 0, sizeof(fprog->interp_mode));
+   memset(prog_data->interp_mode, 0, sizeof(prog_data->interp_mode));
 
    if (!vue_map)
       return;
@@ -75,20 +73,20 @@ brw_setup_vue_interpolation(struct brw_vue_map *vue_map, nir_shader *nir,
     */
    unsigned pos_slot = vue_map->varying_to_slot[VARYING_SLOT_POS];
    if (pos_slot != -1) {;
-      fprog->interp_mode[pos_slot] = INTERP_MODE_NOPERSPECTIVE;
-      fprog->contains_noperspective_varying = true;
+      prog_data->interp_mode[pos_slot] = INTERP_MODE_NOPERSPECTIVE;
+      prog_data->contains_noperspective_varying = true;
    }
 
    foreach_list_typed(nir_variable, var, node, &nir->inputs) {
       unsigned location = var->data.location;
       unsigned slot_count = glsl_count_attribute_slots(var->type, false);
 
-      gen4_frag_prog_set_interp_modes(fprog, vue_map, location, slot_count,
+      gen4_frag_prog_set_interp_modes(prog_data, vue_map, location, slot_count,
                                       var->data.interpolation);
 
       if (location == VARYING_SLOT_COL0 || location == VARYING_SLOT_COL1) {
          location = location + VARYING_SLOT_BFC0 - VARYING_SLOT_COL0;
-         gen4_frag_prog_set_interp_modes(fprog, vue_map, location,
+         gen4_frag_prog_set_interp_modes(prog_data, vue_map, location,
                                          slot_count, var->data.interpolation);
       }
    }
@@ -105,7 +103,7 @@ brw_setup_vue_interpolation(struct brw_vue_map *vue_map, nir_shader *nir,
 
          fprintf(stderr, "%d: %d %s ofs %d\n",
                  i, varying,
-                 get_qual_name(fprog->interp_mode[i]),
+                 get_qual_name(prog_data->interp_mode[i]),
                  brw_vue_slot_to_offset(i));
       }
    }

src/mesa/drivers/dri/i965/brw_nir.c

@@ -343,8 +343,7 @@ brw_nir_lower_tes_inputs(nir_shader *nir, const struct brw_vue_map *vue_map)
 }
 
 void
-brw_nir_lower_fs_inputs(nir_shader *nir, struct brw_vue_map *vue_map,
-                        struct gl_program *prog,
+brw_nir_lower_fs_inputs(nir_shader *nir,
                         const struct gen_device_info *devinfo,
                         const struct brw_wm_prog_key *key)
 {
@@ -375,11 +374,6 @@ brw_nir_lower_fs_inputs(nir_shader *nir, struct brw_vue_map *vue_map,
       }
    }
 
-   if (devinfo->gen < 6) {
-      assert(prog); /* prog will be NULL when called from Vulkan */
-      brw_setup_vue_interpolation(vue_map, nir, prog, devinfo);
-   }
-
    nir_lower_io_options lower_io_options = 0;
    if (key->persample_interp)
       lower_io_options |= nir_lower_io_force_sample_interpolation;

src/mesa/drivers/dri/i965/brw_nir.h

@@ -103,8 +103,7 @@ void brw_nir_lower_vs_inputs(nir_shader *nir,
 void brw_nir_lower_vue_inputs(nir_shader *nir, bool is_scalar,
                               const struct brw_vue_map *vue_map);
 void brw_nir_lower_tes_inputs(nir_shader *nir, const struct brw_vue_map *vue);
-void brw_nir_lower_fs_inputs(nir_shader *nir, struct brw_vue_map *vue_map,
-                             struct gl_program *prog,
+void brw_nir_lower_fs_inputs(nir_shader *nir,
                              const struct gen_device_info *devinfo,
                              const struct brw_wm_prog_key *key);
 void brw_nir_lower_vue_outputs(nir_shader *nir, bool is_scalar);

src/mesa/drivers/dri/i965/brw_program.c

@@ -158,14 +158,7 @@ static struct gl_program *brwNewProgram(struct gl_context *ctx, GLenum target,
    }
 
    case GL_FRAGMENT_PROGRAM_ARB: {
-      struct brw_program *prog;
-      if (brw->gen < 6) {
-         struct gen4_fragment_program *g4_prog =
-            rzalloc(NULL, struct gen4_fragment_program);
-         prog = &g4_prog->base;
-      } else {
-         prog = rzalloc(NULL, struct brw_program);
-      }
+      struct brw_program *prog = rzalloc(NULL, struct brw_program);
 
       if (prog) {
 	 prog->id = get_new_program_id(brw->screen);

src/mesa/drivers/dri/i965/brw_sf.c

@@ -147,7 +147,7 @@ brw_upload_sf_prog(struct brw_context *brw)
                         _NEW_PROGRAM |
                         _NEW_TRANSFORM,
                         BRW_NEW_BLORP |
-                        BRW_NEW_FRAGMENT_PROGRAM |
+                        BRW_NEW_FS_PROG_DATA |
                         BRW_NEW_REDUCED_PRIMITIVE |
                         BRW_NEW_VUE_MAP_GEOM_OUT))
       return;
@@ -203,14 +203,12 @@ brw_upload_sf_prog(struct brw_context *brw)
    if ((ctx->Point.SpriteOrigin == GL_LOWER_LEFT) != render_to_fbo)
       key.sprite_origin_lower_left = true;
 
-   const struct gl_program *fprog = brw->fragment_program;
-   if (fprog) {
-      assert(brw->gen < 6);
-      struct gen4_fragment_program *p = (struct gen4_fragment_program *) fprog;
-
-      /* BRW_NEW_FRAGMENT_PROGRAM */
-      key.contains_flat_varying = p->contains_flat_varying;
-      key.interp_mode = p->interp_mode;
+   /* BRW_NEW_FS_PROG_DATA */
+   const struct brw_wm_prog_data *wm_prog_data =
+      brw_wm_prog_data(brw->wm.base.prog_data);
+   if (wm_prog_data) {
+      key.contains_flat_varying = wm_prog_data->contains_flat_varying;
+      key.interp_mode = wm_prog_data->interp_mode;
    }
 
    /* _NEW_LIGHT | _NEW_PROGRAM */

src/mesa/drivers/dri/i965/brw_sf.h

@@ -47,7 +47,7 @@
 struct brw_sf_prog_key {
    GLbitfield64 attrs;
    bool contains_flat_varying;
-   unsigned char *interp_mode;
+   const unsigned char *interp_mode;
    uint8_t point_sprite_coord_replace;
    GLuint primitive:2;
    GLuint do_twoside_color:1;