[webkit-changes] [WebKit/WebKit] 7dbed2: Implement a more accurate currentStackPointer().

[Commit Queue]

  Branch: refs/heads/main
  Home:   https://github.com/WebKit/WebKit
  Commit: 7dbed20e73b0c8ef5831a07a1bab1135f64b6781
      https://github.com/WebKit/WebKit/commit/7dbed20e73b0c8ef5831a07a1bab1135f64b6781
  Author: Mark Lam <mark.lam at apple.com>
  Date:   2023-02-03 (Fri, 03 Feb 2023)

  Changed paths:
    M Source/JavaScriptCore/llint/LowLevelInterpreter.asm
    M Source/WTF/wtf/StackPointer.cpp
    M Source/WTF/wtf/StackPointer.h

  Log Message:
  -----------
  Implement a more accurate currentStackPointer().
https://bugs.webkit.org/show_bug.cgi?id=251667
rdar://104993866

Reviewed by Justin Michaud.

currentStackPointer() was already accurate for some ports (the ones that support
inline assembly), but for others or when using a Debug build, we fall back to a C++
runtime function that only gives an approximate value.  This patch implements a
currentStackPointer() that is accurate for all currently support ports even when
using a Debug build.

* Source/JavaScriptCore/llint/LowLevelInterpreter.asm:
* Source/WTF/wtf/StackPointer.cpp:
(WTF::currentStackPointer):
* Source/WTF/wtf/StackPointer.h:

Canonical link: https://commits.webkit.org/259818@main