[vm/concurrency] Make box allocation slow paths go to separate runtime entry

The optimizing compiler can insert box instructions at various places
during the optimization pipeline. There is no guarantee that a box
instruction will get a proper (deopt-id, deopt-env) assigned to it - in
many places it will not.

Furthermore StoreInstanceField's into "unboxed fields" might cause
box allocations to happen. Those stores might also not have deopt
information associated with them.

In general we require stackmaps when allocation slow paths go to runtime
and cause GC. If GC throws OOM we theoretically would also need deopt
information in order to populate correct catch-entry state. Though OOM
is uncommon and the VM could decide to ignore the top-frame - if it's
missing deopt information - since box allocations aren't something
users are in control of (as opposed to user-allocated objects inside
try/catch).

=> This CL makes box allocations go to a runtime entry that doesn't
   support lazy-deopt. While being in those runtime entries the mutators
   will also not participate in "deopt safepoint operation" requests.

Issue https://github.com/dart-lang/sdk/issues/45213

TEST=Existing test suite.

Change-Id: I1b61f77e3166da82efad08bb49bc1756576d220c
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/196928
Commit-Queue: Martin Kustermann <kustermann@google.com>
Reviewed-by: Alexander Markov <alexmarkov@google.com>
Reviewed-by: Vyacheslav Egorov <vegorov@google.com>
27 files changed
tree: 5c4807657d8550b8450dbe50fea6c5fce765ddb5
  1. .dart_tool/
  2. .github/
  3. benchmarks/
  4. build/
  5. client/
  6. docs/
  7. pkg/
  8. runtime/
  9. samples/
  10. samples-dev/
  11. samples_2/
  12. sdk/
  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 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.