Revert "Simplify FunctionKind, saving 4 bits in SharedFunctionInfo"

This reverts commit 42667bab5b310b26bfc0ceb300550696cfbbb3ae.

Reason for revert: Breaks msvc compile:

Original change's description:
> Simplify FunctionKind, saving 4 bits in SharedFunctionInfo
> Since we only need to store 18 different function kinds,
> the bitfield approach was wasting space (requiring 11 bits).
> This patch replaces the bitfield with a regular enum, and
> updates all the FunctionKind predicates to use comparisons
> instead of bitwise ops.
> For the small amount of builtin code that depended upon being
> able to do masking to determine whether something is a class
> constructor, we still store two extra bits on FunctionKind,
> which are computed when the SFI is initialized.
> If this approach causes performance regressions (i.e., if it
> turns out that other code was implicitly depending on masking
> for fast checks), we can revert this or address it in
> other ways (e.g., by doing similar caching of repeated checks
> in the caller).
> Change-Id: Iebb3214f564ea8bd7b21e78fda33517d63247124
> Reviewed-on:
> Commit-Queue: Adam Klein <>
> Reviewed-by: Sathya Gunasekaran <>
> Cr-Commit-Position: refs/heads/master@{#50559},

Change-Id: I8e1faa0ca6213d1e70a00fcb417b1bfa35ebd643
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Reviewed-by: Michael Achenbach <>
Commit-Queue: Michael Achenbach <>
Cr-Commit-Position: refs/heads/master@{#50561}
13 files changed
tree: b8ec92a14a307758ac67dc67d6979aa1444360b3
  1. .clang-format
  2. .editorconfig
  3. .git-blame-ignore-revs
  4. .gitignore
  5. .gn
  6. .vpython
  11. ChangeLog
  12. DEPS
  14. LICENSE.fdlibm
  15. LICENSE.strongtalk
  16. LICENSE.v8
  17. LICENSE.valgrind
  18. Makefile
  20. OWNERS
  24. benchmarks/
  25. build_overrides/
  26. codereview.settings
  27. docs/
  28. gni/
  29. gypfiles/
  30. include/
  31. infra/
  32. samples/
  33. snapshot_toolchain.gni
  34. src/
  35. test/
  36. testing/
  37. third_party/
  38. tools/

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:

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/*


Please follow the instructions mentioned on the V8 wiki.