Revert "[wasm][gc] Use SetPermissions to discard pages"

This reverts commit cc71d5ca52159ff1a7f5c736df380f91d4605a88.

Reason for revert: gc-stress failures, e.g. https://ci.chromium.org/p/v8/builders/ci/V8%20Linux%20-%20gc%20stress/22357

Original change's description:
> [wasm][gc] Use SetPermissions to discard pages
> 
> On 32bit windows, DiscardSystemPages fails sometimes (see bug). We don't
> have a reproducer, so this is a purely speculative fix.
> {SetPermissions} has some platform-specific logic to also discard the
> pages. Specifially, on windows it uses {VirtualFree} instead of
> {DiscardVirtualMemory}.
> {SetPermissions} is also semantically stronger, since it forbids any
> further access to the pages.
> 
> R=​mstarzinger@chromium.org
> 
> Bug: v8:8217, chromium:960707
> Change-Id: I8b3325264c86aff8d6e7c6b01c22ae410e87faf4
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1601134
> Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
> Commit-Queue: Clemens Hammacher <clemensh@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#61321}

TBR=mstarzinger@chromium.org,clemensh@chromium.org

Change-Id: Ib2d534a6906ea5d390d08943ea71e1f8799278e8
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: v8:8217, chromium:960707
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1601147
Reviewed-by: Clemens Hammacher <clemensh@chromium.org>
Commit-Queue: Clemens Hammacher <clemensh@chromium.org>
Cr-Commit-Position: refs/heads/master@{#61324}
1 file changed
tree: 80e2c2e86322462a2e11f08aa1cae344a347499f
  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. ChangeLog
  14. DEPS
  15. LICENSE
  16. LICENSE.fdlibm
  17. LICENSE.strongtalk
  18. LICENSE.v8
  19. LICENSE.valgrind
  20. OWNERS
  21. PRESUBMIT.py
  22. README.md
  23. WATCHLISTS
  24. benchmarks/
  25. build_overrides/
  26. codereview.settings
  27. custom_deps/
  28. docs/
  29. gni/
  30. include/
  31. infra/
  32. samples/
  33. snapshot_toolchain.gni
  34. src/
  35. test/
  36. testing/
  37. third_party/
  38. 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.