Vulkan: use one barrier to transit states for all subresources

If a texture follow this rule:
* old usages of all subresources are the same
* new usages of all subresources are the same
Then we can use one barrier to transit states for all subresources.
We don't need to use one barrier per each subresource.

This patch adds a flag at front-end to capture many (but not all)
situations which follow the rule above, then we don't need to loop
over every subresource at Vulkan backend.

Bug: dawn:441
Change-Id: I6124ee2cb09c9142fefd8f057dc6d2659301e2d4
Commit-Queue: Yunchao He <>
Reviewed-by: Corentin Wallez <>
5 files changed
tree: 2e575f0d60041842aa8fd2ff2a2b5da9d16d7c4e
  1. .clang-format
  2. .gitattributes
  3. .gitignore
  4. .gn
  7. CMakeLists.txt
  9. DEPS
  11. OWNERS
  13. README.chromium
  15. build_overrides/
  16. codereview.settings
  17. dawn.json
  18. dawn_wire.json
  19. docs/
  20. examples/
  21. generator/
  22. infra/
  23. scripts/
  24. src/
  25. third_party/
  26. tools/

Dawn, a WebGPU implementation

Dawn is an open-source and cross-platform implementation of the work-in-progress WebGPU standard. More precisely it implements webgpu.h that is a one-to-one mapping with the WebGPU IDL. Dawn is meant to be integrated as part of a larger system and is the underlying implementation of WebGPU in Chromium.

Dawn provides several WebGPU building blocks:

  • WebGPU C/C++ headers that applications and other building blocks use.
    • The webgpu.h version that Dawn implements.
    • A C++ wrapper for the webgpu.h.
  • A “native” implementation of WebGPU using platforms' GPU APIs:
    • D3D12 on Windows 10
    • Metal on macOS and iOS
    • Vulkan on Windows, Linux, ChromeOS, Android and Fuchsia
    • OpenGL as best effort where available
  • A client-server implementation of WebGPU for applications that are in a sandbox without access to native drivers

Helpful links:

Documentation table of content

Developer documentation:

User documentation: (TODO, figure out what overlaps with webgpu.h docs)




Apache 2.0 Public License, please see LICENSE.


This is not an officially supported Google product.