[class] Fix class field name initialization

Previously when class names were computed and set as part of
StoreDataPropertyInLiteral calls, it was observable to static fields
as these static fields are initialized right after the classes were
constructed but before the class names were installed.
This caused the name property to be undefined for this case.

Instead, this patch always forces the creation of a name property on
the class constructor when static class fields are used. This patch
does kill the class boilerplate optimization, but currently all static
class fields are installed using a runtime call to CreateDataProperty
so this isn't any worse when using static class fields.

In the future, this can be optimized away by storing the name on the
boilerplate.

There is spec discussion here:
https://github.com/tc39/proposal-class-fields/issues/85

There isn't a resolution yet, there's still discussion about whether
to have the name be undefined always for static class field
initializers. But, I don't think that's useful as it would always kill
our boilerplate optimization (like this patch does ..., but without the
future optimization potential).

Bug: v8:5367
Change-Id: I14afdf7ece3f2d9fa3c659d2c0bc3806e0b17abb
Reviewed-on: https://chromium-review.googlesource.com/c/1281002
Reviewed-by: Mythri Alle <mythria@chromium.org>
Reviewed-by: Daniel Ehrenberg <littledan@chromium.org>
Reviewed-by: Igor Sheludko <ishell@chromium.org>
Commit-Queue: Sathya Gunasekaran <gsathya@chromium.org>
Cr-Commit-Position: refs/heads/master@{#56686}
3 files changed
tree: aeacbd217ea8a8fec1b51c1056208f9105c7f92d
  1. benchmarks/
  2. build_overrides/
  3. custom_deps/
  4. docs/
  5. gni/
  6. include/
  7. infra/
  8. samples/
  9. src/
  10. test/
  11. testing/
  12. third_party/
  13. tools/
  14. .clang-format
  15. .clang-tidy
  16. .editorconfig
  17. .git-blame-ignore-revs
  18. .gitattributes
  19. .gitignore
  20. .gn
  21. .vpython
  22. .ycm_extra_conf.py
  23. AUTHORS
  24. BUILD.gn
  25. ChangeLog
  26. CODE_OF_CONDUCT.md
  27. codereview.settings
  28. DEPS
  29. LICENSE
  30. LICENSE.fdlibm
  31. LICENSE.strongtalk
  32. LICENSE.v8
  33. LICENSE.valgrind
  34. OWNERS
  35. PRESUBMIT.py
  36. README.md
  37. snapshot_toolchain.gni
  38. WATCHLISTS
README.md

V8 JavaScript Engine

V8 is Google's open source JavaScript engine.

V8 implements ECMAScript as specified in ECMA-262.

V8 is written in C++ and is used in Google Chrome, the open source browser from Google.

V8 can run standalone, or can be embedded into any C++ application.

V8 Project page: https://github.com/v8/v8/wiki

Getting the Code

Checkout depot tools, and run

    fetch v8

This will checkout V8 into the directory v8 and fetch all of its dependencies. To stay up to date, run

    git pull origin
    gclient sync

For fetching all branches, add the following into your remote configuration in .git/config:

    fetch = +refs/branch-heads/*:refs/remotes/branch-heads/*
    fetch = +refs/tags/*:refs/tags/*

Contributing

Please follow the instructions mentioned on the V8 wiki.