PPC/s390: [turbofan] Further optimize DataView accesses.

Port 5fecd146bfbea6edd3a92d52f61462b7455e8f3c

Original Commit Message:

    This adds support for unaligned load/store access to the DataView
    backing store and uses byteswap operations to fix up the endianess
    when necessary. This changes the Word32ReverseBytes operator to be
    a required operator and adds the missing support on the Intel and
    ARM platforms (on 64-bit platforms the Word64ReverseBytes operator
    is also mandatory now).

    This further improves the performance on the dataviewperf.js test
    mentioned in the tracking bug by up to 40%, and at the same time
    reduces the code complexity in the EffectControlLinearizer.

R=bmeurer@chromium.org, joransiu@ca.ibm.com, michael_dawson@ca.ibm.com
BUG=
LOG=N

Change-Id: Ia9aad21713a2ad76ce3ef2b816fc20e9a27fe4c9
Reviewed-on: https://chromium-review.googlesource.com/1174936
Reviewed-by: John Barboza <jbarboza@ca.ibm.com>
Commit-Queue: Junliang Yan <jyan@ca.ibm.com>
Cr-Commit-Position: refs/heads/master@{#55132}
5 files changed
tree: afb8528df910682a4cf79ced3c72194dd3567be6
  1. .clang-format
  2. .editorconfig
  3. .git-blame-ignore-revs
  4. .gitattributes
  5. .gitignore
  6. .gn
  7. .vpython
  8. .ycm_extra_conf.py
  9. AUTHORS
  10. BUILD.gn
  11. CODE_OF_CONDUCT.md
  12. ChangeLog
  13. DEPS
  14. LICENSE
  15. LICENSE.fdlibm
  16. LICENSE.strongtalk
  17. LICENSE.v8
  18. LICENSE.valgrind
  19. OWNERS
  20. PRESUBMIT.py
  21. README.md
  22. WATCHLISTS
  23. benchmarks/
  24. build_overrides/
  25. codereview.settings
  26. custom_deps/
  27. docs/
  28. gni/
  29. include/
  30. infra/
  31. samples/
  32. snapshot_toolchain.gni
  33. src/
  34. test/
  35. testing/
  36. third_party/
  37. tools/
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.