[webkit-changes] [WebKit/WebKit] 0d5431: Make useRandomizingExecutableIslandAllocation do s...

[Justin Michaud]

  Branch: refs/heads/main
  Home:   https://github.com/WebKit/WebKit
  Commit: 0d543178a0704db4a09d4b10ddbee1f964c47fbf
      https://github.com/WebKit/WebKit/commit/0d543178a0704db4a09d4b10ddbee1f964c47fbf
  Author: Justin Michaud <justin_michaud at apple.com>
  Date:   2023-12-21 (Thu, 21 Dec 2023)

  Changed paths:
    M Source/JavaScriptCore/assembler/LinkBuffer.cpp
    M Source/JavaScriptCore/jit/ExecutableAllocator.cpp
    M Source/WTF/wtf/PlatformEnable.h

  Log Message:
  -----------
  Make useRandomizingExecutableIslandAllocation do something when using libpas
https://bugs.webkit.org/show_bug.cgi?id=266645
rdar://119876990

Reviewed by Alexey Shvayka.

Make useRandomizingExecutableIslandAllocation do something when using libpas.
Before enabling the libpas jit heap, this options randomized allocations of
jit memory, allowing us to stress-test jump islands.

This patch adds in some fragmentation. It is not as comprehensive as the original
version of this option, but it is sufficient to trigger the creation of many
jump islands while running JS2.

* Source/JavaScriptCore/jit/ExecutableAllocator.cpp:
* Source/WTF/wtf/PlatformEnable.h:

Canonical link: https://commits.webkit.org/272434@main