230611 - nsCSSFrameConstructor::CharacterDataChanged has to call HasFirstLetterStyle

Status: RESOLVED FIXED

(Core :: Layout, defect)

Description

[Boris Zbarsky [:bzbarsky]]

From a jprof profile of setting nodeValue a bunch of times on a textnode:

 43087  18      651 nsCSSFrameConstructor::ContentChanged
                422 nsCSSFrameConstructor::HaveFirstLetterStyle
                 80 nsTextFrame::ContentChanged
                 69 PresShell::GetPrimaryFrameFor
                 18 nsCSSFrameConstructor::GetFloatContainingBlock
                 12 nsCOMPtr_base::assign_from_helper

So we're spending 2/3 of the total ContentChanged time seeing whether we maybe
have a first-letter frame.  This is about 10% of the total time it takes to set
nodeValue.  There's gotta be a better way to do this.

Comment 1

[Tim]

see attachment 138789 [details] from bug 230609 for the profiled code.

Comment 2

[Boris Zbarsky [:bzbarsky]]

Note that this function has been renamed to CharacterDataChanged.

Maybe we can have a bit on blockframes indicating they have first-letter style?

Comment 3

[Boris Zbarsky [:bzbarsky]]

Fixed by checkin for bug 362901.