[Compile] Ensure we don't reuse a feedback vector with a different layout than expected.

If we flush the bytecode from a SFI we might recompile a JSFunction while the function
still has its old feedback vector. This should usually be fine since the new and old
feedback vectors have the same layout, however some bugs in the parser mean that it's
possible for eagerly and lazily compiled eval functions to have different bytecode and
so potentially different feedback vector layouts.

For now reset the feedback vector if it doesn't have the same size when we compile the
JSFunction, and recreate a new one of the correct layout. This will be replaced with a
CHECK once the parser bugs are fixed.

BUG=chromium:984344,v8:9511

Change-Id: Ib8976f2541516f7a07e4d4ab7dc3c750dfe9b5d4
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1708474
Commit-Queue: Ross McIlroy <rmcilroy@chromium.org>
Commit-Queue: Ulan Degenbaev <ulan@chromium.org>
Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Auto-Submit: Ross McIlroy <rmcilroy@chromium.org>
Cr-Commit-Position: refs/heads/master@{#62800}
2 files changed
tree: fba50a8b7fdef7cac3286bab5f7a4171e17a8399
  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. COMMON_OWNERS
  29. DEPS
  30. ENG_REVIEW_OWNERS
  31. INFRA_OWNERS
  32. INTL_OWNERS
  33. LICENSE
  34. LICENSE.fdlibm
  35. LICENSE.strongtalk
  36. LICENSE.v8
  37. LICENSE.valgrind
  38. MIPS_OWNERS
  39. OWNERS
  40. PPC_OWNERS
  41. PRESUBMIT.py
  42. README.md
  43. S390_OWNERS
  44. 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.