[turbofan] Don't go MEGAMORPHIC when storing oddballs to typed arrays.

The KEYED_STORE_IC was never able to deal with stores to typed arrays
where the value being stored is not already a Number (i.e. either a Smi
or a HeapNumber). By extending it to also handle Oddballs (i.e. true,
false, undefined and null) and teaching TurboFan to also perform the
appropriate check plus the truncation to Number, we can easily support
this use case as well.

On the micro-benchmark in the bug report, we go from

  typedArrayStoreBool: 2975 ms.
  typedArrayStoreInt: 44 ms.

to

  typedArrayStoreBool: 43 ms.
  typedArrayStoreInt: 44 ms.

so that's roughly a 70x performance boost.

Bug: chromium:287773
Change-Id: I227419aeabc3f5b6793aa280a95448d03ac2f2dd
Reviewed-on: https://chromium-review.googlesource.com/691731
Commit-Queue: Benedikt Meurer <bmeurer@chromium.org>
Reviewed-by: Michael Stanton <mvstanton@chromium.org>
Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#48257}
2 files changed
tree: ab7f4325d72a563c9c15e995f8a219f8de7be1ee
  1. benchmarks/
  2. build_overrides/
  3. docs/
  4. gni/
  5. gypfiles/
  6. include/
  7. infra/
  8. samples/
  9. src/
  10. test/
  11. testing/
  12. third_party/
  13. tools/
  14. .clang-format
  15. .editorconfig
  16. .gitignore
  17. .gn
  18. .ycm_extra_conf.py
  19. AUTHORS
  20. BUILD.gn
  21. ChangeLog
  22. CODE_OF_CONDUCT.md
  23. codereview.settings
  24. DEPS
  25. LICENSE
  26. LICENSE.fdlibm
  27. LICENSE.strongtalk
  28. LICENSE.v8
  29. LICENSE.valgrind
  30. Makefile
  31. Makefile.android
  32. OWNERS
  33. PRESUBMIT.py
  34. README.md
  35. snapshot_toolchain.gni
  36. 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.