Improve performance when calling PaintLayer::setNeedsRepaint()

third_party/WebKit/Source/core/layout/LayoutObject.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2000 Dirk Mueller (mueller@kde.org)
  *           (C) 2004 Allan Sandfeld Jensen (kde@carewolf.com)
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2011 Apple Inc. All rights reserved.
  * Copyright (C) 2009 Google Inc. All rights reserved.
  * Copyright (C) 2009 Torch Mobile Inc. All rights reserved. (http://www.torchmobile.com/)
  *
  * This library is free software; you can redistribute it and/or
@@ skipping 1232 matching lines @@
         if (const PaintLayer* paintInvalidationLayer = enclosingLayer->enclosingLayerForPaintInvalidationCrossingFrameBoundaries())
             paintInvalidationLayer->layoutObject()->invalidateDisplayItemClientOnBacking(displayItemClient, PaintInvalidationFull);
         enclosingLayer->setNeedsRepaint();
     }
 }
 
 void LayoutObject::invalidateDisplayItemClients(const LayoutBoxModelObject& paintInvalidationContainer, PaintInvalidationReason invalidationReason) const
 {
     paintInvalidationContainer.invalidateDisplayItemClientOnBacking(*this, invalidationReason);
 
     if (PaintLayer* enclosingLayer = this->enclosingLayer())

[chrishtr, 2016/01/15 00:02:21]

In particular, this is still calling setNeedsRepaint in the new version.

[Xianzhu, 2016/01/15 00:32:05]

Oops. Sorry I thought I had removed these two lines.

Done.

         enclosingLayer->setNeedsRepaint();
 }
 
 LayoutRect LayoutObject::boundsRectForPaintInvalidation(const LayoutBoxModelObject& paintInvalidationContainer, const PaintInvalidationState* paintInvalidationState) const
 {
     return PaintLayer::computePaintInvalidationRect(*this, paintInvalidationContainer.layer(), paintInvalidationState);
 }
 
 const LayoutBoxModelObject* LayoutObject::invalidatePaintRectangleInternal(const LayoutRect& dirtyRect) const
 {
@@ skipping 10 matching lines @@
     PaintLayer::mapRectToPaintInvalidationBacking(this, &paintInvalidationContainer, dirtyRectOnBacking);
     invalidatePaintUsingContainer(paintInvalidationContainer, dirtyRectOnBacking, PaintInvalidationRectangle);
     return &paintInvalidationContainer;
 }
 
 void LayoutObject::invalidatePaintRectangle(const LayoutRect& rect) const
 {
     const LayoutBoxModelObject* paintInvalidationContainer = invalidatePaintRectangleInternal(rect);
     if (paintInvalidationContainer)
         invalidateDisplayItemClients(*paintInvalidationContainer, PaintInvalidationRectangle);
+    if (PaintLayer* enclosingLayer = this->enclosingLayer())
+        enclosingLayer->setNeedsRepaint();
 }
 
 void LayoutObject::invalidatePaintRectangleNotInvalidatingDisplayItemClients(const LayoutRect& r) const
 {
     invalidatePaintRectangleInternal(r);
 }
 
 void LayoutObject::invalidateTreeIfNeeded(PaintInvalidationState& paintInvalidationState)
 {
     ASSERT(!needsLayout());
@@ skipping 129 matching lines @@
     if (!isFullPaintInvalidationReason(invalidationReason) && boxDecorationBackgroundObscured != m_bitfields.lastBoxDecorationBackgroundObscured())
         invalidationReason = PaintInvalidationBackgroundObscurationChange;
     m_bitfields.setLastBoxDecorationBackgroundObscured(boxDecorationBackgroundObscured);
 
     if (invalidationReason == PaintInvalidationNone) {
         // TODO(trchen): Currently we don't keep track of paint offset of layout objects.
         // There are corner cases that the display items need to be invalidated for paint offset
         // mutation, but incurs no pixel difference (i.e. bounds stay the same) so no rect-based
         // invalidation is issued. See crbug.com/508383 and crbug.com/515977.
         // This is a workaround to force display items to update paint offset.
-        if (!RuntimeEnabledFeatures::slimmingPaintOffsetCachingEnabled() && paintInvalidationState.forcedSubtreeInvalidationWithinContainer())
+        if (!RuntimeEnabledFeatures::slimmingPaintOffsetCachingEnabled() && paintInvalidationState.forcedSubtreeInvalidationWithinContainer()) {
             invalidateDisplayItemClients(paintInvalidationContainer, invalidationReason);
+            paintInvalidationState.enclosingLayer().setNeedsRepaint();
+        }
 
         return invalidationReason;
     }
 
     invalidateDisplayItemClients(paintInvalidationContainer, invalidationReason);
+    paintInvalidationState.enclosingLayer().setNeedsRepaint();
 
     if (invalidationReason == PaintInvalidationIncremental) {
         incrementallyInvalidatePaint(paintInvalidationContainer, oldBounds, newBounds, newLocation);
         return invalidationReason;
     }
 
     fullyInvalidatePaint(paintInvalidationContainer, invalidationReason, oldBounds, newBounds);
 
     return invalidationReason;
 }
@@ skipping 1948 matching lines @@
         if (!enclosingLayer)
             return;
         const PaintLayer* paintInvalidationLayer = enclosingLayer->enclosingLayerForPaintInvalidationCrossingFrameBoundaries();
         if (!paintInvalidationLayer)
             return;
         paintInvalidationContainer = paintInvalidationLayer->layoutObject();
     }
 
     traverseNonCompositingDescendants(const_cast<LayoutObject&>(*this), [&paintInvalidationContainer, paintInvalidationReason](LayoutObject& object) {
         object.invalidateDisplayItemClients(*paintInvalidationContainer, paintInvalidationReason);
+        if (object.hasLayer())
+            toLayoutBoxModelObject(object).layer()->setNeedsRepaint();
     });
 }
 
 void LayoutObject::invalidatePaintOfPreviousPaintInvalidationRect(const LayoutBoxModelObject& paintInvalidationContainer, PaintInvalidationReason reason)
 {
+    invalidatePaintOfPreviousPaintInvalidationRectNotSettingLayerNeedsRepaint(paintInvalidationContainer, reason);
+    if (PaintLayer* enclosingLayer = this->enclosingLayer())
+        enclosingLayer->setNeedsRepaint();
+}
+
+void LayoutObject::invalidatePaintOfPreviousPaintInvalidationRectNotSettingLayerNeedsRepaint(const LayoutBoxModelObject& paintInvalidationContainer, PaintInvalidationReason reason)
+{

[chrishtr, 2016/01/14 18:51:13]

This looks like a copy of the old code. I expected to see deleted lines where
setNeedsRepaint() was removed.

[Xianzhu, 2016/01/14 19:19:08]

Now invalidateDisplayItemClients() doesn't set layers needs repaint, but the
callers do instead. This function becomes 'NotSettingLayerNeedsRepaint' because
of the change of invalidateDisplayItemClients().

[chrishtr, 2016/01/15 00:02:21]

I understand the goal, but can't find where you are changing it to not
setNeedsRepaint where it was doing so before. You changed line 3434 to
invalidatePaintOfPreviousPaintInvalidationRectNotSettingLayerNeedsRepaint(), but

as far as I can tell, the definition of
invalidatePaintOfPreviousPaintInvalidationRectNotSettingLayerNeedsRepaint() is
the same
as it was before.. ?

     // These disablers are valid because we want to use the current compositing/invalidation status.
     DisablePaintInvalidationStateAsserts invalidationDisabler;
     DisableCompositingQueryAsserts compositingDisabler;
 
     LayoutRect invalidationRect = previousPaintInvalidationRect();
     adjustInvalidationRectForCompositedScrolling(invalidationRect, paintInvalidationContainer);
     invalidatePaintUsingContainer(paintInvalidationContainer, invalidationRect, PaintInvalidationLayer);
     invalidateDisplayItemClients(paintInvalidationContainer, PaintInvalidationLayer);
 
     // This method may be used to invalidate paint of an object changing paint invalidation container.
     // Clear previous paint invalidation rect on the original paint invalidation container to avoid
     // under-invalidation if the new paint invalidation rect on the new paint invalidation container
     // happens to be the same as the old one.
     clearPreviousPaintInvalidationRects();
 }
 
 void LayoutObject::invalidatePaintIncludingNonCompositingDescendants()
 {
     // Since we're only painting non-composited layers, we know that they all share the same paintInvalidationContainer.
     const LayoutBoxModelObject& paintInvalidationContainer = containerForPaintInvalidation();
     traverseNonCompositingDescendants(*this, [&paintInvalidationContainer](LayoutObject& object) {
-        object.invalidatePaintOfPreviousPaintInvalidationRect(paintInvalidationContainer, PaintInvalidationLayer);
+        object.invalidatePaintOfPreviousPaintInvalidationRectNotSettingLayerNeedsRepaint(paintInvalidationContainer, PaintInvalidationLayer);
+        if (object.hasLayer())
+            toLayoutBoxModelObject(object).layer()->setNeedsRepaint();
     });
 }
 
 // FIXME: If we had a flag to force invalidations in a whole subtree, we could get rid of this function (crbug.com/410097).
 void LayoutObject::setShouldDoFullPaintInvalidationIncludingNonCompositingDescendants()
 {
     // Need to access the current compositing status.
     DisableCompositingQueryAsserts disabler;
     traverseNonCompositingDescendants(*this, [](LayoutObject& object) {
         object.setShouldDoFullPaintInvalidation();
@@ skipping 70 matching lines @@
         const blink::LayoutObject* root = object1;
         while (root->parent())
             root = root->parent();
         root->showLayoutTreeAndMark(object1, "*", object2, "-", 0);
     } else {
         fprintf(stderr, "Cannot showLayoutTree. Root is (nil)\n");
     }
 }
 
 #endif