[wasm-simd] Implement load_splat and load_extend

Introduce new operator LoadTransform that holds a LoadTransformInfo param,
which describes the kind of load (normal, unaligned, protected), and a
transformation (splat or extend, signed or unsigned).

We have a new method that a full decoder needs to implement, LoadTransform,
which resuses the existing LoadType we have, but also takes a LoadTransform,
to distinguish between splats and extends at the decoder level.

This implements 4 out of the 10 suggested load splat/extend operations
(to keep the cl smaller), and is also missing interpreter support (will
be added in the future).



Change-Id: I1e65c693bfbe30e2a511c81b5a32e06aacbddc19
Bug: v8:9886
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1863863
Reviewed-by: Tobias Tebbi <tebbi@chromium.org>
Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Reviewed-by: Andreas Haas <ahaas@chromium.org>
Commit-Queue: Zhi An Ng <zhin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#64819}
18 files changed
tree: 1248749aa9e45b7f29f0efa4e1e6bd2fecf828b8
  1. build_overrides/
  2. custom_deps/
  3. docs/
  4. gni/
  5. include/
  6. infra/
  7. samples/
  8. src/
  9. test/
  10. testing/
  11. third_party/
  12. tools/
  13. .clang-format
  14. .clang-tidy
  15. .editorconfig
  16. .flake8
  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.