102617 2012-11-18 12:00:33 -0800 Add a 'has flipped blocks' bit somewhere to optimize stuff 2015-05-06 12:37:22 -0700 1 1 1 Unclassified WebKit Layout and Rendering 528+ (Nightly build) Unspecified Unspecified RESOLVED FIXED P2 Normal --- 1 simon.fraser zalan dbates hyatt kling koivisto leviw nduca ojan psolanki sabouhallawa simon.fraser zalan oldest_to_newest 770165 0 simon.fraser 2012-11-18 12:00:33 -0800 canMapBetweenRenderers() has to walk renderers looking for flipped blocks, which is unfortunate because this slows down the layer->layer mapping optimization there. A bit on RenderLayer that says "hasFlippedBlocks contents" would help. 780630 1 simon.fraser 2012-11-30 20:53:27 -0800 I also note that RenderBox::topLeftLocationOffset() is expensive, about 2% of the total time when scrolling a layer-heavy page. If we could do a quick check for flipped blocks, we could probably avoid the containingBlock() call and make it much faster. 1092288 2 hyatt 2015-05-06 12:37:22 -0700 I added this, so this bug can be closed.