[pkg/vm] Handle switch statements in unreachable code eliminator.

Namely, if the tested expression for a switch statement is constant,
then we can remove any constant cases where the constants differ,
and if all but a single case is removed, we can replace the switch
with the case body.

If constant functions are not enabled, then getters annotated with
@pragma("vm:platform-const") are still evaluated with the constant
function evaluation machinery, but only those and no others (including
any functions called within an annotated getter). This way, functions
can be annotated with @pragma("vm:platform-const") without having to
rewrite them to be a single returned expression.

TEST=pkg/vm/test/transformations/unreachable_code_elimination
     pkg/vm/test/transformations/vm_constant_evaluator

Issue: https://github.com/dart-lang/sdk/issues/50473
Issue: https://github.com/dart-lang/sdk/issues/31969
Change-Id: Ie290d2f1f469326238d66c3d9631f8e696685ff0
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/332760
Commit-Queue: Tess Strickland <sstrickl@google.com>
Reviewed-by: Chloe Stefantsova <cstefantsova@google.com>
Reviewed-by: Alexander Markov <alexmarkov@google.com>
12 files changed
tree: 94b8682d7c099013a9bfaeac6bd314c84862a39c
  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. .vpython
  22. AUTHORS
  23. BUILD.gn
  24. CHANGELOG.md
  25. codereview.settings
  26. CONTRIBUTING.md
  27. DEPS
  28. LICENSE
  29. OWNERS
  30. PATENT_GRANT
  31. PRESUBMIT.py
  32. README.dart-sdk
  33. README.md
  34. sdk.code-workspace
  35. sdk_args.gni
  36. SECURITY.md
  37. WATCHLISTS
README.md

Dart

A client-optimized language for fast apps on any platform

Dart is:

  • Optimized for UI: Develop with a programming language specialized around the needs of user interface creation.

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

  • Fast on all platforms: Compile to ARM & x64 machine code for mobile, desktop, and backend. Or compile to JavaScript for the web.

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 on our wiki.

Contributing to Dart

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

You can also contribute patches, as described in Contributing.