Mesa (master): anv: Avoid emitting UBO surface states that won't be used

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Module: Mesa
Branch: master
Commit: beca63c6c07f7263a56a3517ba0fec6fe6335325
URL:    http://cgit.freedesktop.org/mesa/mesa/commit/?id=beca63c6c07f7263a56a3517ba0fec6fe6335325

Author: Jason Ekstrand <jason at jlekstrand.net>
Date:   Tue Oct 29 16:10:49 2019 -0500

anv: Avoid emitting UBO surface states that won't be used

This shaves around 4-5% off of a CPU-limited example running with the
Dawn WebGPU implementation.

Reviewed-by: Lionel Landwerlin <lionel.g.landwerlin at intel.com>
Reviewed-by: Kenneth Graunke <kenneth at whitecape.org>

---

 src/intel/vulkan/genX_cmd_buffer.c | 13 ++++++++++++-
 1 file changed, 12 insertions(+), 1 deletion(-)

diff --git a/src/intel/vulkan/genX_cmd_buffer.c b/src/intel/vulkan/genX_cmd_buffer.c
index af7ced32e39..6c1cd04f336 100644
--- a/src/intel/vulkan/genX_cmd_buffer.c
+++ b/src/intel/vulkan/genX_cmd_buffer.c
@@ -2118,7 +2118,8 @@ emit_binding_table(struct anv_cmd_buffer *cmd_buffer,
       return VK_SUCCESS;
    }
 
-   struct anv_pipeline_bind_map *map = &pipeline->shaders[stage]->bind_map;
+   struct anv_shader_bin *bin = pipeline->shaders[stage];
+   struct anv_pipeline_bind_map *map = &bin->bind_map;
    if (map->surface_count == 0) {
       *bt_state = (struct anv_state) { 0, };
       return VK_SUCCESS;
@@ -2292,6 +2293,16 @@ emit_binding_table(struct anv_cmd_buffer *cmd_buffer,
          break;
 
       case VK_DESCRIPTOR_TYPE_UNIFORM_BUFFER_DYNAMIC:
+         /* If the shader never does any UBO pulls (this is a fairly common
+          * case) then we don't need to fill out those binding table entries.
+          * The real cost savings here is that we don't have to build the
+          * surface state for them which is surprisingly expensive when it's
+          * on the hot-path.
+          */
+         if (!bin->prog_data->has_ubo_pull)
+            continue;
+         /* Fall through */
+
       case VK_DESCRIPTOR_TYPE_STORAGE_BUFFER_DYNAMIC: {
          /* Compute the offset within the buffer */
          uint32_t dynamic_offset =