ilo: handle NULL renderbuffers correctly

Renderbuffers may be NULL since 9baa45f78b.

src/gallium/drivers/ilo/ilo_3d_pipeline_gen6.c

@@ -892,7 +892,11 @@ gen6_pipeline_state_surfaces_rt(struct ilo_3d_pipeline *p,
          const struct ilo_surface_cso *surface =
             (const struct ilo_surface_cso *) fb->state.cbufs[i];
 
-         if (fb->offset_to_layers) {
+         if (!surface) {
+            surface_state[i] =
+               gen6_emit_SURFACE_STATE(p->dev, &fb->null_rt, true, p->cp);
+         }
+         else if (fb->offset_to_layers) {
             struct ilo_view_surface layer;
 
             assert(surface->base.u.tex.first_layer ==
@@ -920,14 +924,8 @@ gen6_pipeline_state_surfaces_rt(struct ilo_3d_pipeline *p,
        * brw_update_renderbuffer_surfaces() does.  I don't know why.
        */
       if (i == 0) {
-         struct ilo_view_surface null_surface;
-
-         ilo_gpe_init_view_surface_null(p->dev,
-               fb->state.width, fb->state.height,
-               1, 0, &null_surface);
-
          surface_state[i] =
-            gen6_emit_SURFACE_STATE(p->dev, &null_surface, true, p->cp);
+            gen6_emit_SURFACE_STATE(p->dev, &fb->null_rt, true, p->cp);
 
          i++;
       }

src/gallium/drivers/ilo/ilo_blit.h

@@ -179,8 +179,11 @@ ilo_blit_resolve_framebuffer(struct ilo_context *ilo)
       }
    }
 
-   for (i = 0; i < fb->nr_cbufs; i++)
-      ilo_blit_resolve_surface(ilo, fb->cbufs[i], ILO_TEXTURE_RENDER_WRITE);
+   for (i = 0; i < fb->nr_cbufs; i++) {
+      struct pipe_surface *surf = fb->cbufs[i];
+      if (surf)
+         ilo_blit_resolve_surface(ilo, surf, ILO_TEXTURE_RENDER_WRITE);
+   }
 
    if (fb->zsbuf)
       ilo_blit_resolve_surface(ilo, fb->zsbuf, ILO_TEXTURE_RENDER_WRITE);

src/gallium/drivers/ilo/ilo_gpe.h

@@ -256,6 +256,7 @@ struct ilo_surface_cso {
 struct ilo_fb_state {
    struct pipe_framebuffer_state state;
 
+   struct ilo_view_surface null_rt;
    struct ilo_zs_surface null_zs;
 
    unsigned num_samples;
@@ -528,8 +529,8 @@ ilo_gpe_init_fs_cso(const struct ilo_dev_info *dev,
 }
 
 void
-ilo_gpe_init_fb(const struct ilo_dev_info *dev,
-                const struct pipe_framebuffer_state *state,
-                struct ilo_fb_state *fb);
+ilo_gpe_set_fb(const struct ilo_dev_info *dev,
+               const struct pipe_framebuffer_state *state,
+               struct ilo_fb_state *fb);
 
 #endif /* ILO_GPE_H */

src/gallium/drivers/ilo/ilo_gpe_gen6.c

@@ -2458,21 +2458,30 @@ ilo_gpe_init_sampler_cso(const struct ilo_dev_info *dev,
 }
 
 void
-ilo_gpe_init_fb(const struct ilo_dev_info *dev,
-                const struct pipe_framebuffer_state *state,
-                struct ilo_fb_state *fb)
+ilo_gpe_set_fb(const struct ilo_dev_info *dev,
+               const struct pipe_framebuffer_state *state,
+               struct ilo_fb_state *fb)
 {
    const struct pipe_surface *first;
-   unsigned num_surfaces;
+   unsigned num_surfaces, first_idx;
 
    ILO_GPE_VALID_GEN(dev, 6, 7.5);
 
    util_copy_framebuffer_state(&fb->state, state);
 
-   first = (state->nr_cbufs) ? state->cbufs[0] :
-           (state->zsbuf) ? state->zsbuf :
-           NULL;
-   num_surfaces = state->nr_cbufs + !!state->zsbuf;
+   ilo_gpe_init_view_surface_null(dev,
+         state->width, state->height,
+         1, 0, &fb->null_rt);
+
+   first = NULL;
+   for (first_idx = 0; first_idx < state->nr_cbufs; first_idx++) {
+      if (state->cbufs[first_idx]) {
+         first = state->cbufs[first_idx];
+         break;
+      }
+   }
+   if (!first)
+      first = state->zsbuf;
 
    fb->num_samples = (first) ? first->texture->nr_samples : 1;
    if (!fb->num_samples)
@@ -2484,6 +2493,8 @@ ilo_gpe_init_fb(const struct ilo_dev_info *dev,
     * The PRMs list several restrictions when the framebuffer has more than
     * one surface, but it seems they are lifted on GEN7+.
     */
+   num_surfaces = state->nr_cbufs + !!state->zsbuf;
+
    if (dev->gen < ILO_GEN(7) && num_surfaces > 1) {
       const unsigned first_depth =
          (first->texture->target == PIPE_TEXTURE_3D) ?
@@ -2492,11 +2503,15 @@ ilo_gpe_init_fb(const struct ilo_dev_info *dev,
       bool has_3d_target = (first->texture->target == PIPE_TEXTURE_3D);
       unsigned i;
 
-      for (i = 1; i < num_surfaces; i++) {
+      for (i = first_idx + 1; i < num_surfaces; i++) {
          const struct pipe_surface *surf =
             (i < state->nr_cbufs) ? state->cbufs[i] : state->zsbuf;
-         const unsigned depth =
-            (surf->texture->target == PIPE_TEXTURE_3D) ?
+         unsigned depth;
+
+         if (!surf)
+            continue;
+
+         depth = (surf->texture->target == PIPE_TEXTURE_3D) ?
             surf->texture->depth0 :
             surf->u.tex.last_layer - surf->u.tex.first_layer + 1;
 

src/gallium/drivers/ilo/ilo_gpe_gen6.h

@@ -2109,7 +2109,7 @@ gen6_emit_BLEND_STATE(const struct ilo_dev_info *dev,
       const struct ilo_blend_cso *cso = &blend->cso[idx];
       const int num_samples = fb->num_samples;
       const struct util_format_description *format_desc =
-         (idx < fb->state.nr_cbufs) ?
+         (idx < fb->state.nr_cbufs && fb->state.cbufs[idx]) ?
          util_format_description(fb->state.cbufs[idx]->format) : NULL;
       bool rt_is_unorm, rt_is_pure_integer, rt_dst_alpha_forced_one;
 

src/gallium/drivers/ilo/ilo_state.c

@@ -644,7 +644,7 @@ ilo_set_framebuffer_state(struct pipe_context *pipe,
 {
    struct ilo_context *ilo = ilo_context(pipe);
 
-   ilo_gpe_init_fb(ilo->dev, state, &ilo->fb);
+   ilo_gpe_set_fb(ilo->dev, state, &ilo->fb);
 
    ilo->dirty |= ILO_DIRTY_FB;
 }
@@ -1310,7 +1310,8 @@ ilo_mark_states_with_resource_dirty(struct ilo_context *ilo,
    /* for now? */
    if (res->target != PIPE_BUFFER) {
       for (i = 0; i < ilo->fb.state.nr_cbufs; i++) {
-         if (ilo->fb.state.cbufs[i]->texture == res) {
+         const struct pipe_surface *surf = ilo->fb.state.cbufs[i];
+         if (surf && surf->texture == res) {
             states |= ILO_DIRTY_FB;
             break;
          }