Bug 69106

Summary: Universal attribute selectors disable style sharing
Product: WebKit Reporter: Antti Koivisto <koivisto>
Component: CSSAssignee: Nobody <webkit-unassigned>
Status: RESOLVED FIXED    
Severity: Normal CC: dglazkov, hyatt, webkit.review.bot
Priority: P2    
Version: 528+ (Nightly build)   
Hardware: Unspecified   
OS: Unspecified   
Attachments:
Description Flags
patch hyatt: review+, webkit.review.bot: commit-queue-

Description Antti Koivisto 2011-09-29 14:45:32 PDT
Selectors of type [foo="bar"] will end up marking every element style with the affectedByUncommonAttributeSelectors bit, rendering style sharing inoperative. This happens on http://www.whatwg.org/specs/web-apps/current-work/ for example.
Comment 1 Antti Koivisto 2011-09-29 14:46:30 PDT
affectedByAttributeSelectors bit I mean
Comment 2 Antti Koivisto 2011-09-29 15:00:45 PDT
Created attachment 109209 [details]
patch
Comment 3 Antti Koivisto 2011-09-29 15:01:18 PDT
This speeds up style matching and applying ~15% on full HTML5 spec (=~0.7s). Sharing percentage goes from 0% to ~30%. Increased sharing should also save a substantial amount of memory.
Comment 4 Dave Hyatt 2011-09-29 15:04:22 PDT
Comment on attachment 109209 [details]
patch

r=me
Comment 5 WebKit Review Bot 2011-09-29 15:51:17 PDT
Comment on attachment 109209 [details]
patch

Attachment 109209 [details] did not pass chromium-ews (chromium-xvfb):
Output: http://queues.webkit.org/results/9901202

New failing tests:
tables/mozilla/bugs/bug222846.html
Comment 6 Antti Koivisto 2011-09-30 00:07:11 PDT
http://trac.webkit.org/changeset/96393 (with a fix to the crashing test)
Comment 7 Alexey Proskuryakov 2012-06-06 15:12:44 PDT
This has caused bug 88196.