tint/ast: Derive off `ast::Variable`

Add the new classes:
* `ast::Let`
* `ast::Override`
* `ast::Parameter`
* `ast::Var`

Limit the fields to those that are only applicable for their type.

Note: The resolver and validator is a tangled mess for each of the
variable types. This CL tries to keep the functionality exactly the
same. I'll clean this up in another change.

Bug: tint:1582
Change-Id: Iee83324167ffd4d92ae3032b2134677629c90079
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/93780
Reviewed-by: Dan Sinclair <dsinclair@chromium.org>
Commit-Queue: Ben Clayton <bclayton@chromium.org>
Kokoro: Kokoro <noreply+kokoro@google.com>
66 files changed
tree: 5737a2efafc41becacca4b44c88d34899179177d
  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.