[webkit-reviews] review requested: [Bug 13021] XPath can be very slow : [Attachment 13890] partial fix 3 v2

[bugzilla-daemon at webkit.org]

Alexey Proskuryakov <ap at webkit.org> has asked  for review:
Bug 13021: XPath can be very slow
http://bugs.webkit.org/show_bug.cgi?id=13021

Attachment 13890: partial fix 3 v2
http://bugs.webkit.org/attachment.cgi?id=13890&action=edit

------- Additional Comments from Alexey Proskuryakov <ap at webkit.org>
I have checked the generated code for "return v" vs. "return nodes", and the
former was definitely better (it enabled return value optimization). So, looks
like my measurement just showed a random fluctuation, since this code is not
particularly hot.

Changed Value to make it nicer and safer to use.

These changes didn't affect performance, so thanks to the improvements from bug
13190 it's just under 12 ms on my machine now (vs. 16 ms in Firefox 2 and 10 ms
in Firefox 3).