AX: De-virtualize AXCoreObject::isDetachedFromParent

[Tyler Wilcock]

This function is called in hot paths and takes non-insignificant amounts of time in samples.

[Radar WebKit Bug Importer]

<rdar://problem/109018200>

[Tyler Wilcock]

Created attachment 466266 [details]
Patch

[Andres Gonzalez]

(In reply to Tyler Wilcock from comment #2)
> Created attachment 466266 [details]
> Patch

--- a/Source/WebCore/accessibility/AccessibilityMockObject.cpp
+++ b/Source/WebCore/accessibility/AccessibilityMockObject.cpp


+void AccessibilityMockObject::setParent(AccessibilityObject* parent)
+{
+    m_parent = parent;
+    m_isDetachedFromParent = !parent;
+}

Do we even need to keep m_isDetachedFromParent? I'd think that we could tell whether has a parent or not just by checking m_parent.

--- a/Source/WebCore/accessibility/AccessibilityObjectInterface.h
+++ b/Source/WebCore/accessibility/AccessibilityObjectInterface.h

-    virtual bool isDetachedFromParent() = 0;
+    // Intentionally non-virtual because this is called in hot paths.
+    bool isDetachedFromParent() const { return m_isDetachedFromParent; }

Again, don't think we need m_isDetachedFromParent, check for the parent instead.