vulkan/bvh: Add option to override leaf builder SPIR-Vs

With this, drivers can compile and use custom leaf builder versions
instead of the generic common shader.

Reviewed-by: Konstantin Seurer <konstantin.seurer@gmail.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/32797>

src/vulkan/runtime/vk_acceleration_structure.c

@@ -506,12 +506,27 @@ build_leaves(VkCommandBuffer commandBuffer,
     */
     VkResult result;
    if (updateable) {
-      result = get_pipeline_spv(device, meta, VK_META_OBJECT_KEY_LEAF_ALWAYS_ACTIVE,
-                                leaf_always_active_spv,
-                                sizeof(leaf_always_active_spv),
-                                sizeof(struct leaf_args), args, &pipeline, &layout);
+      const uint32_t *spirv = leaf_always_active_spv;
+      size_t spirv_size = sizeof(leaf_always_active_spv);
+
+      if (device->as_build_ops->leaf_always_active_spirv_override) {
+         spirv = device->as_build_ops->leaf_always_active_spirv_override;
+         spirv_size = device->as_build_ops->leaf_always_active_spirv_override_size;
+      }
+
+      result = get_pipeline_spv(device, meta, VK_META_OBJECT_KEY_LEAF_ALWAYS_ACTIVE, spirv,
+                                spirv_size, sizeof(struct leaf_args), args,
+                                &pipeline, &layout);
    } else {
-      result = get_pipeline_spv(device, meta, VK_META_OBJECT_KEY_LEAF, leaf_spv, sizeof(leaf_spv),
+      const uint32_t *spirv = leaf_spv;
+      size_t spirv_size = sizeof(leaf_spv);
+
+      if (device->as_build_ops->leaf_spirv_override) {
+         spirv = device->as_build_ops->leaf_spirv_override;
+         spirv_size = device->as_build_ops->leaf_spirv_override_size;
+      }
+
+      result = get_pipeline_spv(device, meta, VK_META_OBJECT_KEY_LEAF, spirv, spirv_size,
                                 sizeof(struct leaf_args), args, &pipeline, &layout);
    }
 

src/vulkan/runtime/vk_acceleration_structure.h

@@ -93,6 +93,11 @@ struct vk_acceleration_structure_build_ops {
                                         uint32_t leaf_count,
                                         struct vk_acceleration_structure *src,
                                         struct vk_acceleration_structure *dst);
+
+   const uint32_t *leaf_spirv_override;
+   size_t leaf_spirv_override_size;
+   const uint32_t *leaf_always_active_spirv_override;
+   size_t leaf_always_active_spirv_override_size;
 };
 
 struct vk_acceleration_structure_build_args {