[builtins] Speedup Object.keys by adding a fast path for objects without elements, interceptors, ...

This speeds up the for-of-object benchmark at
http://kpdecker.github.io/six-speed/ by >2x.

BUG=

Review URL: https://codereview.chromium.org/1682873003

Cr-Commit-Position: refs/heads/master@{#33867}
2 files changed
tree: 52150b01b0ec8b37f26c42d54a15433d56acdc88
  1. benchmarks/
  2. build/
  3. docs/
  4. include/
  5. infra/
  6. samples/
  7. src/
  8. test/
  9. testing/
  10. third_party/
  11. tools/
  12. .clang-format
  13. .gitignore
  14. .ycm_extra_conf.py
  15. AUTHORS
  16. BUILD.gn
  17. ChangeLog
  18. codereview.settings
  19. DEPS
  20. LICENSE
  21. LICENSE.strongtalk
  22. LICENSE.v8
  23. LICENSE.valgrind
  24. Makefile
  25. Makefile.android
  26. Makefile.nacl
  27. OWNERS
  28. PRESUBMIT.py
  29. README.md
  30. snapshot_toolchain.gni
  31. 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.