RESOLVED FIXED 115116
CSS attribute selectors cause unnecessary style recalc when setting attribute to same value.
https://bugs.webkit.org/show_bug.cgi?id=115116
Summary CSS attribute selectors cause unnecessary style recalc when setting attribute...
Andreas Kling
Reported Wednesday, April 24, 2013 6:06:31 PM UTC
Setting an attribute to the same value it already has should never trigger a style recalc due to attribute selectors. The code is currently too dumb to figure this out, and ends up restyling the same stuff over and over.
Attachments
Proposed patch (2.21 KB, patch)
2013-04-24 10:26 PDT, Andreas Kling
simon.fraser: review+
Radar WebKit Bug Importer
Comment 1 Wednesday, April 24, 2013 6:07:27 PM UTC
Andreas Kling
Comment 2 Wednesday, April 24, 2013 6:26:13 PM UTC
Created attachment 199498 [details] Proposed patch
Simon Fraser (smfr)
Comment 3 Wednesday, April 24, 2013 6:38:28 PM UTC
Comment on attachment 199498 [details] Proposed patch View in context: https://bugs.webkit.org/attachment.cgi?id=199498&action=review > Source/WebCore/ChangeLog:13 > + This reduces unnecessary style recalculation in MAS content. "MAS" is pretty meaningless in this context.
Antti Koivisto
Comment 4 Wednesday, April 24, 2013 6:41:33 PM UTC
Comment on attachment 199498 [details] Proposed patch View in context: https://bugs.webkit.org/attachment.cgi?id=199498&action=review Better fixes involve some significant refactoring, this is ok for now. > Source/WebCore/dom/Element.cpp:-878 > else if (name == HTMLNames::pseudoAttr) > shouldInvalidateStyle |= testShouldInvalidateStyle && isInShadowTree(); > > - shouldInvalidateStyle |= testShouldInvalidateStyle && styleResolver->hasSelectorForAttribute(name.localName()); It seem wrong that attributeChanged() is called when attribute does not change. It would be better to fix that. > Source/WebCore/dom/Element.cpp:2726 > + if (oldValue != newValue) { > + if (attached() && document()->styleResolver() && document()->styleResolver()->hasSelectorForAttribute(name.localName())) > + setNeedsStyleRecalc(); > + } Bit sad that the invalidation code gets spread around like this.
Andreas Kling
Comment 5 Wednesday, April 24, 2013 6:42:21 PM UTC
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