Changeset 183725 in webkit

Timestamp:

May 2, 2015 5:53:18 PM (9 years ago)

Author:

akling@apple.com

Message:

Style recalc always causes detach from shared StyleRareNonInheritedData.
<​https://webkit.org/b/144530>

Reviewed by Darin Adler.

StyleResolver::adjustStyleForMaskImages() was always calling RenderStyle::ensureMaskLayers()
when we were in style recalc. This caused the RenderStyle to COW off from the previously
shared StyleRareNonInheritedData even if nothing actually changes.

This patch adds an early return to adjustStyleForMaskImages() when the previous style had
no mask images. Further refinements could be made, but this covers the most common case where
we don't have any mask images at all.

• css/StyleResolver.cpp:

(WebCore::StyleResolver::adjustStyleForMaskImages):

Location:

trunk/Source/WebCore

Files:

• ChangeLog (modified) (1 diff)
• css/StyleResolver.cpp (modified) (1 diff)

trunk/Source/WebCore/ChangeLog

@@ +1 @@
+2015-05-02  Andreas Kling  <akling@apple.com>
+
+        Style recalc always causes detach from shared StyleRareNonInheritedData.
+        <https://webkit.org/b/144530>
+
+        Reviewed by Darin Adler.
+
+        StyleResolver::adjustStyleForMaskImages() was always calling RenderStyle::ensureMaskLayers()
+        when we were in style recalc. This caused the RenderStyle to COW off from the previously
+        shared StyleRareNonInheritedData even if nothing actually changes.
+
+        This patch adds an early return to adjustStyleForMaskImages() when the previous style had
+        no mask images. Further refinements could be made, but this covers the most common case where
+        we don't have any mask images at all.
+
+        * css/StyleResolver.cpp:
+        (WebCore::StyleResolver::adjustStyleForMaskImages):
+
 2015-05-02  Alexey Proskuryakov  <ap@apple.com>
 

trunk/Source/WebCore/css/StyleResolver.cpp

@@ -1181 +1181 @@
             oldMaskLayer = oldMaskLayer->next();
         }
-        
+
+        if (oldStyleMaskImages.isEmpty())
+            return;
+
         // Try to match the new mask objects through the list from the old style.
         // This should work perfectly and optimal when the list of masks remained