[webkit-changes] [WebKit/WebKit] 8517a5: AX: Don't eagerly AXIsolatedTree::updateNode if we...

[Tyler Wilcock]

  Branch: refs/heads/main
  Home:   https://github.com/WebKit/WebKit
  Commit: 8517a5aa953f09087683eaf0e7f55c410ad94956
      https://github.com/WebKit/WebKit/commit/8517a5aa953f09087683eaf0e7f55c410ad94956
  Author: Tyler Wilcock <tyler_w at apple.com>
  Date:   2023-09-26 (Tue, 26 Sep 2023)

  Changed paths:
    M Source/WebCore/accessibility/isolatedtree/AXIsolatedTree.cpp

  Log Message:
  -----------
  AX: Don't eagerly AXIsolatedTree::updateNode if we're collecting unresolved appends
https://bugs.webkit.org/show_bug.cgi?id=262077
rdar://problem/116018776

Reviewed by Chris Fleizach.

This patch features two optimizations:

  1. Change AXIsolatedTree::updateChildrenForObjects to not resolve node
     changes between each object update.
  2. Do not eagerly AXIsolatedTree::updateNode if we're gathering
     m_unresolvedPendingAppends.

Both allow for a lot more de-duplication in m_unresolvedPendingAppends,
resulting in much fewer node changes created on some pages.

On an internal webpage, before this patch we created ~165k node
changes in response to a dynamic change. After this patch, we create
~132k node changes.

* Source/WebCore/accessibility/isolatedtree/AXIsolatedTree.cpp:
(WebCore::AXIsolatedTree::updateNode):
(WebCore::AXIsolatedTree::updateChildrenForObjects):

Canonical link: https://commits.webkit.org/268466@main