Lots of time spent querying table cell borders, when there are none.
https://bugs.webkit.org/show_bug.cgi?id=143277
Reviewed by Simon Fraser.
This patch speeds up collapsed border queries by using existing collapsed border
cache to calculate repaint rects and by introducing a fast path for zero width collapsed borders.
It reduces the number of calls to recompute collapsed borders from 36 000 to 1 600, while loading a page with a table of 400 rows (1 cell per row).
When scrolling the same page all the way down to the bottom, the number of calls to recompute collapsed borders falls from 290 000 to 0.
Covered by existing tests.
* rendering/RenderTable.cpp:
(WebCore::RenderTable::styleDidChange): This moves invalidation time from RenderTable::layout() to styleDidChange().
(WebCore::RenderTable::invalidateCollapsedBorders):
(WebCore::RenderTable::recalcCollapsedBorders):
* rendering/RenderTable.h:
(WebCore::RenderTable::collapsedBordersAreValid):
(WebCore::RenderTable::invalidateCollapsedBorders): Deleted.
* rendering/RenderTableCell.cpp:
(WebCore::RenderTableCell::RenderTableCell):
(WebCore::RenderTableCell::willBeRemovedFromTree): Invalidate caches so that when repaint rect is calculated, we don't end up using stale values.
(WebCore::RenderTableCell::styleDidChange): Same as willBeRemovedFromTree.
(WebCore::RenderTableCell::collapsedStartBorder): Check if collapsed border is zero -also query cache.
(WebCore::RenderTableCell::collapsedEndBorder):
(WebCore::RenderTableCell::collapsedBeforeBorder):
(WebCore::RenderTableCell::collapsedAfterBorder):
(WebCore::RenderTableCell::cachedCollapsedLeftBorder):
(WebCore::RenderTableCell::cachedCollapsedRightBorder):
(WebCore::RenderTableCell::cachedCollapsedTopBorder):
(WebCore::RenderTableCell::cachedCollapsedBottomBorder):
(WebCore::RenderTableCell::paintCollapsedBorders):
(WebCore::RenderTableCell::cellAtLeft): Deleted.
(WebCore::RenderTableCell::cellAtRight): Deleted.
(WebCore::RenderTableCell::cellAtTop): Deleted.
(WebCore::RenderTableCell::cellAtBottom): Deleted.
* rendering/RenderTableCell.h:
(WebCore::RenderTableCell::invalidateHasEmptyCollapsedBorders):
* rendering/RenderTableCol.cpp:
(WebCore::RenderTableCol::styleDidChange):
* rendering/RenderTableRow.cpp:
(WebCore::RenderTableRow::styleDidChange):
(WebCore::RenderTableRow::addChild):
* rendering/RenderTableSection.cpp:
(WebCore::RenderTableSection::styleDidChange):
(WebCore::RenderTableSection::clearCachedCollapsedBorders): This is just an extra safety to invalidate collapsed border cache. This is always
called together with RenderTable::invalidateCollapsedBorders() -and that should prevent the RenderCells to use the cache.
(WebCore::RenderTableSection::removeCachedCollapsedBorders):
(WebCore::RenderTableSection::setCachedCollapsedBorder):
(WebCore::RenderTableSection::cachedCollapsedBorder):
* rendering/RenderTableSection.h:
git-svn-id: http://svn.webkit.org/repository/webkit/trunk@182235 268f45cc-cd09-0410-ab3c-d52691b4dbfc
9 files changed
