Revert "[vm] Improvements in the BitField API."

This reverts commit bfc1a445273ee21ad80d3cb52597a4606b591233.

Reason for revert: Broke Windows build.

Original change's description:
> [vm] Improvements in the BitField API.
>
> If no position is specified, then the bitfield starts at bit 0.
>
> The default size for bool BitFields is 1 instead of the remaining
> bits in the container.
>
> If the size of the value type is smaller than the remaining bits
> in the container, then the size of the value type is used as
> the default size instead.
>
> If a signed value is used in a non-sign-extended BitField, only
> the magnitude of the value is stored, not the sign bit. This means
> the actual size of the bitfield may be one less than the requested
> size in this case.
>
> If the requested size of the bitfield is larger than the size of the
> value type, a compile-time error is thrown. (For signed types, the
> requested size is allowed to be the size of the entire value, even if
> only the magnitude bits are stored.)
>
> Rework uses of BitFields to avoid using separate constants for
> bit positions/sizes except for macro-defined bitfields (which now
> are universally bool, and so size 1).
>
> TEST=vm/cc/BitFields_Defaults
>
> Change-Id: I40711c929d2e5165ce40823772beb49e8cfdb820
> Cq-Include-Trybots: luci.dart.try:vm-aot-dwarf-linux-product-x64-try,vm-aot-linux-debug-x64c-try,vm-aot-linux-release-x64-try,vm-aot-mac-release-arm64-try,vm-aot-linux-release-simarm_x64-try
> Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/381644
> Reviewed-by: Ryan Macnak <rmacnak@google.com>
> Commit-Queue: Tess Strickland <sstrickl@google.com>

Change-Id: I13bf2218ecc47a42f3a6091821037b51b56618fb
Cq-Include-Trybots: luci.dart.try:vm-aot-dwarf-linux-product-x64-try,vm-aot-linux-debug-x64c-try,vm-aot-linux-release-x64-try,vm-aot-mac-release-arm64-try,vm-aot-linux-release-simarm_x64-try
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/382380
Bot-Commit: Rubber Stamper <rubber-stamper@appspot.gserviceaccount.com>
Reviewed-by: Martin Kustermann <kustermann@google.com>
Commit-Queue: Tess Strickland <sstrickl@google.com>
16 files changed
tree: 64a81392b6e1ec97ca86ae5582d664846eccd683
  1. .dart_tool/
  2. .github/
  3. benchmarks/
  4. build/
  5. docs/
  6. pkg/
  7. runtime/
  8. samples/
  9. sdk/
  10. tests/
  11. third_party/
  12. tools/
  13. utils/
  14. .clang-format
  15. .gitattributes
  16. .gitconfig
  17. .gitignore
  18. .gn
  19. .mailmap
  20. .style.yapf
  21. AUTHORS
  22. BUILD.gn
  23. CHANGELOG.md
  24. codereview.settings
  25. CONTRIBUTING.md
  26. DEPS
  27. LICENSE
  28. OWNERS
  29. PATENT_GRANT
  30. PRESUBMIT.py
  31. README.dart-sdk
  32. README.md
  33. sdk.code-workspace
  34. sdk_args.gni
  35. sdk_packages.yaml
  36. SECURITY.md
  37. WATCHLISTS
README.md

Dart

An approachable, portable, and productive language for high-quality apps on any platform

Dart is:

  • Approachable: Develop with a strongly typed programming language that is consistent, concise, and offers modern language features like null safety and patterns.

  • Portable: Compile to ARM, x64, or RISC-V machine code for mobile, desktop, and backend. Compile to JavaScript or WebAssembly for the web.

  • Productive: Make changes iteratively: use hot reload to see the result instantly in your running app. Diagnose app issues using DevTools.

Dart's flexible compiler technology lets you run Dart code in different ways, depending on your target platform and goals:

  • Dart Native: For programs targeting devices (mobile, desktop, server, and more), Dart Native includes both a Dart VM with JIT (just-in-time) compilation and an AOT (ahead-of-time) compiler for producing machine code.

  • Dart Web: For programs targeting the web, Dart Web includes both a development time compiler (dartdevc) and a production time compiler (dart2js).

Dart platforms illustration

License & patents

Dart is free and open source.

See LICENSE and PATENT_GRANT.

Using Dart

Visit dart.dev to learn more about the language, tools, and to find codelabs.

Browse pub.dev for more packages and libraries contributed by the community and the Dart team.

Our API reference documentation is published at api.dart.dev, based on the stable release. (We also publish docs from our beta and dev channels, as well as from the primary development branch).

Building Dart

If you want to build Dart yourself, here is a guide to getting the source, preparing your machine to build the SDK, and building.

There are more documents in our repo at docs.

Contributing to Dart

The easiest way to contribute to Dart is to file issues.

You can also contribute patches, as described in Contributing.

Roadmap

Future plans for Dart are included in the combined Dart and Flutter roadmap on the Flutter wiki.