[Mesa-dev] [PATCH v4 16/18] anv/cmd_buffer: Skip some input attachment transitions

[Nanley Chery]

Signed-off-by: Nanley Chery <nanley.g.chery at intel.com>
---
 src/intel/vulkan/genX_cmd_buffer.c | 31 ++++++++++++++++++++++++++-----
 1 file changed, 26 insertions(+), 5 deletions(-)

diff --git a/src/intel/vulkan/genX_cmd_buffer.c b/src/intel/vulkan/genX_cmd_buffer.c
index 7b2a3551b6..611e77bddb 100644
--- a/src/intel/vulkan/genX_cmd_buffer.c
+++ b/src/intel/vulkan/genX_cmd_buffer.c
@@ -2763,14 +2763,12 @@ cmd_buffer_subpass_transition_layouts(struct anv_cmd_buffer * const cmd_buffer,
           * this is not the last use of the buffer. The layout should not have
           * changed from the first call and no transition is necessary.
           */
-         assert(att_ref->layout == att_state->current_layout);
+         assert(att_state->current_layout == att_ref->layout ||
+                att_state->current_layout ==
+                VK_IMAGE_LAYOUT_COLOR_ATTACHMENT_OPTIMAL);
          continue;
       }
 
-      /* Get the appropriate target layout for this attachment. */
-      const VkImageLayout target_layout = subpass_end ?
-         att_desc->final_layout : att_ref->layout;
-
       /* The attachment index must be less than the number of attachments
        * within the framebuffer.
        */
@@ -2780,6 +2778,29 @@ cmd_buffer_subpass_transition_layouts(struct anv_cmd_buffer * const cmd_buffer,
          cmd_state->framebuffer->attachments[att_ref->attachment];
       const struct anv_image * const image = iview->image;
 
+      /* Get the appropriate target layout for this attachment. */
+      VkImageLayout target_layout;
+
+      /* A resolve is necessary before use as an input attachment if the clear
+       * color or auxiliary buffer usage isn't supported by the sampler.
+       */
+      const bool input_needs_resolve =
+            (att_state->fast_clear && !att_state->clear_color_is_zero_one) ||
+            att_state->input_aux_usage != att_state->aux_usage;
+      if (subpass_end) {
+         target_layout = att_desc->final_layout;
+      } else if (iview->aspect_mask == VK_IMAGE_ASPECT_COLOR_BIT &&
+                 !input_needs_resolve) {
+         /* Layout transitions before the final only help to enable sampling as
+          * an input attachment. If the input attachment supports sampling
+          * using the auxiliary surface, we can skip such transitions by making
+          * the target layout one that is CCS-aware.
+          */
+         target_layout = VK_IMAGE_LAYOUT_COLOR_ATTACHMENT_OPTIMAL;
+      } else {
+         target_layout = att_ref->layout;
+      }
+
       /* Perform the layout transition. */
       if (image->aspects & VK_IMAGE_ASPECT_DEPTH_BIT) {
          transition_depth_buffer(cmd_buffer, image,
-- 
2.13.3