[json] Fold allocation of mutable heap numbers

Instead of allocating a fixed array in which we write individually allocate
mutable heap numbers, we can allocate a byte array large enough to cover all
heap numbers. That avoids expensive allocation calls, write barriers, and
temporary memory O(number of heap numbers) (we'll just have 1 byte empty byte
array as overhead).

Change-Id: I4ffe16dd91e97a2e8cd8e36ff5af37375599276b
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1613993
Auto-Submit: Toon Verwaest <verwaest@chromium.org>
Reviewed-by: Igor Sheludko <ishell@chromium.org>
Commit-Queue: Toon Verwaest <verwaest@chromium.org>
Cr-Commit-Position: refs/heads/master@{#61581}
1 file changed
tree: 98c750982c2e51a9b2a3d245188acbc94b3bbfbd
  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. ENG_REVIEW_OWNERS
  30. INFRA_OWNERS
  31. LICENSE
  32. LICENSE.fdlibm
  33. LICENSE.strongtalk
  34. LICENSE.v8
  35. LICENSE.valgrind
  36. OWNERS
  37. PRESUBMIT.py
  38. README.md
  39. snapshot_toolchain.gni
  40. 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://v8.dev/docs

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 at v8.dev/docs/contribute.