[webkit-reviews] review denied: [Bug 76335] Reduce HandleHeap churn when managing weak handles. : [Attachment 122572] Proposed patch

[bugzilla-daemon at webkit.org]

Geoffrey Garen <ggaren at apple.com> has denied Andreas Kling <kling at webkit.org>'s
request for review:
Bug 76335: Reduce HandleHeap churn when managing weak handles.
https://bugs.webkit.org/show_bug.cgi?id=76335

Attachment 122572: Proposed patch
https://bugs.webkit.org/attachment.cgi?id=122572&action=review

------- Additional Comments from Geoffrey Garen <ggaren at apple.com>
View in context: https://bugs.webkit.org/attachment.cgi?id=122572&action=review


Just curious: Is this performance issue measurable somewhere?

PassWeak<T> seems like a good idea to me, but it needs to work like PassOwnPtr,
not like PassRefPtr, since weak references are single-owner.

> Source/JavaScriptCore/heap/Weak.h:51
> +    PassWeak(const Weak<T>& o)
> +	   : m_slot(o.slot())
> +    {
> +    }

The only way to create a PassWeak from a Weak should be to release the Weak.
This behavior shares the Handle, which is incorrect, since the original Weak
can delete the Handle at any time.