[ptr-compr][turbofan] Adding Phi reductions to DecompressionElimination

This reduction replaces the Phi's input decompressions with their parent
node, if and only if all of the Phi's inputs are Decompress nodes.

Also, if we have different Decompress nodes as inputs, we need to use
a conservative decompression after the Phi.

Cq-Include-Trybots: luci.v8.try:v8_linux64_pointer_compression_rel_ng
Cq-Include-Trybots: luci.v8.try:v8_linux64_arm64_pointer_compression_rel_ng
Bug: v8:8977, v8:7703
Change-Id: I8cc0264f9d08fe5ad25364f18c9f305afc54529c
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1624785
Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
Commit-Queue: Santiago Aboy Solanes <solanes@chromium.org>
Cr-Commit-Position: refs/heads/master@{#61820}
3 files changed
tree: c5a95dc7f28ad98dcf1601aae087928ca87b9b2b
  1. .clang-format
  2. .clang-tidy
  3. .editorconfig
  4. .git-blame-ignore-revs
  5. .gitattributes
  6. .gitignore
  7. .gn
  8. .vpython
  9. .ycm_extra_conf.py
  10. AUTHORS
  11. BUILD.gn
  12. CODE_OF_CONDUCT.md
  13. COMMON_OWNERS
  14. ChangeLog
  15. DEPS
  16. ENG_REVIEW_OWNERS
  17. INFRA_OWNERS
  18. LICENSE
  19. LICENSE.fdlibm
  20. LICENSE.strongtalk
  21. LICENSE.v8
  22. LICENSE.valgrind
  23. OWNERS
  24. PRESUBMIT.py
  25. README.md
  26. WATCHLISTS
  27. benchmarks/
  28. build_overrides/
  29. codereview.settings
  30. custom_deps/
  31. docs/
  32. gni/
  33. include/
  34. infra/
  35. samples/
  36. src/
  37. test/
  38. testing/
  39. third_party/
  40. 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://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.