[webkit-reviews] review denied: [Bug 31415] [v8] do not copy data twice when converting short v8 string into WebCore::String : [Attachment 43872] Addressing Darin's concerns

[bugzilla-daemon at webkit.org]

Dmitry Titov <dimich at chromium.org> has denied anton muhin
<antonm at chromium.org>'s request for review:
Bug 31415: [v8] do not copy data twice when converting short v8 string into
WebCore::String
https://bugs.webkit.org/show_bug.cgi?id=31415

Attachment 43872: Addressing Darin's concerns
https://bugs.webkit.org/attachment.cgi?id=43872&action=review

------- Additional Comments from Dmitry Titov <dimich at chromium.org>
Darin Fisher and I discussed it a bit. Although he's noted the style issues, he
didn't mean to say the discussion we had before is concluded.

Usually, perf improvement should measurably improve perf, so if there is no
test but you say it can easily be created then lets add a test, measure and
know what we are gaining. Having a test also prevents possible regressions. We
have a v8-specific set of tests in src/data/dom_perf - could you add a specific
test here?

Again, if there is no measurable difference, I don't see why make the change.
Agree there could be an extra copy of up to 16 bytes to a stack array. But if
it's impossible to measure, why split the code at all?

r- because it needs a test.