tint: Add basic support for chromium_experimental_push_constant.

This extension adds support for the push_constant storage class such
that it can be tested with WGSL test files. The real goal is to allow
future transforms that will add push constants that the SPIRV writer
will output.

The extension:

 - Adds the `chromium_experimental_push_constant` enable.
 - Allows the push_constant storage class for global variables.
 - Adds validation that the types are host-shareable for push_constant
   variables, and that they don't contain f16 (must be 32bit types
   only).
 - Validates that at most one push_constant variable is statically used
   per entry-point.
 - Skips validation that the extension has been enabled if
   kIgnoreStorageClass is used.

Tests are added:

 - For parsing of var<push_constant>
   - Caught a missing conversion.
 - For each of the validation rules.
 - For the wrapping of push constants in structs if needed by
   AddSpirvBlockAttribute.
 - For the layout and type rules of the storage class.
 - For a shader with multiple entry-points using various push constants.
    - Caught a missing reset of the previous push constant variable in
      the validation check that at most one is used.
    - Caught the missing wrapping in structs that had to be added to
      AddSpirvBlockAttribute.
    - Caught incorrect logic when adding diagnostics about the call
      graph leading to the reference to push constants.

Bug: tint:1620
Change-Id: I04a5d8e5188c0dcef077f2233ba1359d1575bf51
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/96682
Kokoro: Kokoro <noreply+kokoro@google.com>
Commit-Queue: Corentin Wallez <cwallez@chromium.org>
Reviewed-by: Ben Clayton <bclayton@google.com>
31 files changed
tree: c63c97a4bebb3b68a1a1cf78999437e80269e9de
  1. .vscode/
  2. build_overrides/
  3. docs/
  4. generator/
  5. include/
  6. infra/
  7. scripts/
  8. src/
  9. test/
  10. third_party/
  11. tools/
  12. webgpu-cts/
  13. .clang-format
  14. .clang-tidy
  15. .gitattributes
  16. .gitignore
  17. .gn
  18. AUTHORS
  19. BUILD.gn
  20. CMakeLists.txt
  21. CMakeSettings.json
  22. CODE_OF_CONDUCT.md
  23. codereview.settings
  24. CONTRIBUTING.md
  25. CPPLINT.cfg
  26. dawn.json
  27. dawn_wire.json
  28. DEPS
  29. DIR_METADATA
  30. Doxyfile
  31. go.mod
  32. go.sum
  33. LICENSE
  34. OWNERS
  35. PRESUBMIT.py
  36. README.chromium
  37. README.md
  38. tint_overrides_with_defaults.gni
README.md

Dawn's logo: a sun rising behind a stylized mountain inspired by the WebGPU logo. The text Dawn is written below it.

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
  • Tint is a compiler for the WebGPU Shader Language (WGSL).

Helpful links:

Documentation table of content

Developer documentation:

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

Status

(TODO)

License

Apache 2.0 Public License, please see LICENSE.

Disclaimer

This is not an officially supported Google product.