Revert "Re-land "[vm] Aggressive write-barrier elimination.""

This reverts commit eff1a9ff9706f2f6285668f6d0e2c44c42518aac.

Reason for revert:
  Causes flaky hits of RELEASE_ASSERT in marker.cc, see b/151131634.

Original change's description:
> Re-land "[vm] Aggressive write-barrier elimination."
> 
> The original revision is in Patchset 3.
> 
> Four bugs were fixed:
> 
> 1. JoinEntryInstr::SuccessorCount() is not the correct way to get the
>    number of successor blocks from the Join block;
>    JoinEntryInstr::last_instruction()->SuccessorCount() must be used
>    instead.
> 
> 2. BitVector::Equals() was non-deterministically returning 'false'
>    for equal vectors.
> 
> 3. All blocks need to be processed at least once during the Analysis
>    phase (not only in the SaveResults phase).
> 
> 4. We were not removing write barriers from StoreIndexed instructions,
>    even though we had support for it.
> 
> This reverts commit 7fd8ad5a2d233137920fe20390f08646bfdafeca.
> 
> Fixes https://github.com/dart-lang/sdk/issues/40780
> 
> Change-Id: I9650ec2c547ec49cf88ca0524e14f6c245621f6a
> Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/138086
> Commit-Queue: Samir Jindel <sjindel@google.com>
> Reviewed-by: Martin Kustermann <kustermann@google.com>
> Reviewed-by: Ryan Macnak <rmacnak@google.com>

TBR=kustermann@google.com,rmacnak@google.com,sjindel@google.com

Change-Id: If9afd84465175fad2431405a97e9293c8bd5e476
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/138808
Reviewed-by: Martin Kustermann <kustermann@google.com>
Commit-Queue: Martin Kustermann <kustermann@google.com>
28 files changed
tree: 1beeec4b52d85f0e084f05217acd8f5cc17f20b9
  1. .dart_tool/
  2. .github/
  3. benchmarks/
  4. build/
  5. client/
  6. docs/
  7. pkg/
  8. runtime/
  9. samples/
  10. samples-dev/
  11. sdk/
  12. sdk_nnbd/
  13. tests/
  14. third_party/
  15. tools/
  16. utils/
  17. .clang-format
  18. .gitattributes
  19. .gitconfig
  20. .gitignore
  21. .gn
  22. .mailmap
  23. .packages
  24. .style.yapf
  25. .vpython
  26. AUTHORS
  27. BUILD.gn
  28. CHANGELOG.md
  29. codereview.settings
  30. CONTRIBUTING.md
  31. DEPS
  32. LICENSE
  33. PATENT_GRANT
  34. PRESUBMIT.py
  35. README.dart-sdk
  36. README.md
  37. sdk_args.gni
  38. 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 the dart.dev to learn more about the language, tools, getting started, and more.

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

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.