tint: Implement sem::Load

The resolver now wraps sem::Expression objects with a sem::Load object
anywhere that the load rule is invoked. sem::Expression provides an
`UnwrapLoad()` method that returns the inner expression (or
passthrough, if no load is present), which is analaguous to
Type::UnwrapRef().

The logic for alias analysis in `RegisterLoadIfNeeded` has been folded
into the new `Resolver::Load` method.

Fixed up many transforms and tests. The only difference in output is
for a single SPIR-V backend test, where some IDs have changed due to
slight re-ordering of when expressions are generated.

There may be further clean-ups possible (e.g. removing unnecessary
calls to `UnwrapRef`, and simplifying places in the SPIR-V writer or
transforms that deal with memory accesses), but these can be addressed
in future patches.

Fixed: tint:1654
Change-Id: I69adecfe9251faae46546b64d0cdc29eea26cd4e
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/99706
Commit-Queue: James Price <jrprice@google.com>
Kokoro: Kokoro <noreply+kokoro@google.com>
Reviewed-by: Antonio Maiorano <amaiorano@google.com>
Reviewed-by: Ben Clayton <bclayton@google.com>
39 files changed
tree: 9ba121eb37ffd548bb27c1d8095cdd2d5abdd60d
  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. go_presubmit_support.py
  34. LICENSE
  35. OWNERS
  36. PRESUBMIT.py
  37. README.chromium
  38. README.md
  39. 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, Metal, Vulkan and OpenGL. See per API support for more details.
  • 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) that can be used in standalone to convert shaders from and to 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.