Skip paint property update and visual rect update if no geometry change

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/)
@@ skipping 1611 matching lines @@
                  ? object->parent()
                  : object->containingBlock();
     if (object)
       object->setChildNeedsOverflowRecalcAfterStyleChange();
   } while (object);
 }
 
 void LayoutObject::setNeedsOverflowRecalcAfterStyleChange() {
   bool neededRecalc = needsOverflowRecalcAfterStyleChange();
   setSelfNeedsOverflowRecalcAfterStyleChange();
+  setNeedsPaintOffsetAndVisualRectUpdate();
   if (!neededRecalc)
     markAncestorsForOverflowRecalcIfNeeded();
 }
 
 DISABLE_CFI_PERF
 void LayoutObject::setStyle(PassRefPtr<ComputedStyle> style) {
   ASSERT(style);
 
   if (m_style == style) {
     // We need to run through adjustStyleDifference() for iframes, plugins, and
@@ skipping 79 matching lines @@
 
   if (diff.needsRecomputeOverflow() && !needsLayout()) {
     // TODO(rhogan): Make inlines capable of recomputing overflow too.
     if (isLayoutBlock())
       setNeedsOverflowRecalcAfterStyleChange();
     else
       setNeedsLayoutAndPrefWidthsRecalc(LayoutInvalidationReason::StyleChange);
   }
 
   if (diff.needsPaintInvalidationSubtree() ||
-      updatedDiff.needsPaintInvalidationSubtree())
+      updatedDiff.needsPaintInvalidationSubtree()) {
     setShouldDoFullPaintInvalidationIncludingNonCompositingDescendants();
-  else if (diff.needsPaintInvalidationObject() ||
-           updatedDiff.needsPaintInvalidationObject())
-    setShouldDoFullPaintInvalidation();
+  } else if (diff.needsPaintInvalidationObject() ||
+             updatedDiff.needsPaintInvalidationObject()) {
+    // TODO(wangxianzhu): For now LayoutSVGRoot::localVisualRect() depends on
+    // several styles. Refactor to avoid this special case.
+    if (isSVGRoot())
+      setShouldDoFullPaintInvalidation();
+    else
+      setShouldDoFullPaintInvalidationWithoutGeometryChange();
+  }
+
+  // Visibility affects visual rect.
+  if (oldStyle && oldStyle->visibility() != m_style->visibility())
+    setNeedsPaintOffsetAndVisualRectUpdate();
 
   // Text nodes share style with their parents but the paint properties don't
   // apply to them, hence the !isText() check.
   if (RuntimeEnabledFeatures::slimmingPaintInvalidationEnabled() && !isText() &&
       (diff.transformChanged() || diff.opacityChanged() ||
        diff.zIndexChanged() || diff.filterChanged() ||
        diff.backdropFilterChanged() || diff.cssClipChanged())) {
     setNeedsPaintPropertyUpdate();
 
     // We don't need to invalidate paint of objects on SPv2 when only paint
@@ skipping 1660 matching lines @@
   }
 }
 
 inline void LayoutObject::markAncestorsForPaintInvalidation() {
   for (
       LayoutObject* parent = this->paintInvalidationParent();
       parent &&
       !parent
            ->shouldCheckForPaintInvalidationRegardlessOfPaintInvalidationState();
       parent = parent->paintInvalidationParent())
-    parent->m_bitfields.setChildShouldCheckForPaintInvalidation(true);
+    parent->m_bitfields.setMayNeedPaintInvalidation(true);
+}
+
+inline void LayoutObject::setNeedsPaintOffsetAndVisualRectUpdate() {
+  if (needsPaintOffsetAndVisualRectUpdate())
+    return;
+  m_bitfields.setNeedsPaintOffsetAndVisualRectUpdate(true);
+  for (LayoutObject* parent = paintInvalidationParent();
+       parent && !parent->needsPaintOffsetAndVisualRectUpdate();
+       parent = parent->paintInvalidationParent())
+    parent->m_bitfields.setNeedsPaintOffsetAndVisualRectUpdate(true);
 }
 
 void LayoutObject::setShouldInvalidateSelection() {
   if (!canUpdateSelectionOnRootLineBoxes())
     return;
   m_bitfields.setShouldInvalidateSelection(true);
-  markAncestorsForPaintInvalidation();
+  setMayNeedPaintInvalidation();
   frameView()->scheduleVisualUpdateForPaintInvalidationIfNeeded();
 }
 
 void LayoutObject::setShouldDoFullPaintInvalidation(
     PaintInvalidationReason reason) {
+  setNeedsPaintOffsetAndVisualRectUpdate();

[pdr., 2017/03/10 06:21:39]

Can this be called during paint invalidation? I think this might be what the
PropertyTreeBuilderContext DCHECKS are for (parentUpdated). If so, WDYT about
adding a DCHECK that needsPaintOffsetAndVisualRectUpdate is not set to true
during the prepaint walk?

[Xianzhu, 2017/03/10 17:43:05]

This can be called during paint invalidation (e.g. when we find paint offset
change in SPv2), but it should only change flags of objects that have not been
walked. The xxxUpdated flags can partly ensure the rule. We can add additional
flags in LayoutObject to enforce the rule. Will think more about this.

+  setShouldDoFullPaintInvalidationWithoutGeometryChange(reason);
+}
+
+void LayoutObject::setShouldDoFullPaintInvalidationWithoutGeometryChange(
+    PaintInvalidationReason reason) {
   // Only full invalidation reasons are allowed.
-  ASSERT(isFullPaintInvalidationReason(reason));
+  DCHECK(isFullPaintInvalidationReason(reason));
 
   bool isUpgradingDelayedFullToFull =
       m_bitfields.fullPaintInvalidationReason() ==
           PaintInvalidationDelayedFull &&
       reason != PaintInvalidationDelayedFull;
 
   if (m_bitfields.fullPaintInvalidationReason() == PaintInvalidationNone ||
       isUpgradingDelayedFullToFull) {
     if (reason == PaintInvalidationFull)
       reason =
           documentLifecycleBasedPaintInvalidationReason(document().lifecycle());
     m_bitfields.setFullPaintInvalidationReason(reason);
     if (!isUpgradingDelayedFullToFull)
       markAncestorsForPaintInvalidation();
   }
 
   frameView()->scheduleVisualUpdateForPaintInvalidationIfNeeded();
 }
 
 void LayoutObject::setMayNeedPaintInvalidation() {
+  setNeedsPaintOffsetAndVisualRectUpdate();
+  setMayNeedPaintInvalidationWithoutGeometryChange();
+}
+
+void LayoutObject::setMayNeedPaintInvalidationWithoutGeometryChange() {
   if (mayNeedPaintInvalidation())
     return;
   m_bitfields.setMayNeedPaintInvalidation(true);
   markAncestorsForPaintInvalidation();
   frameView()->scheduleVisualUpdateForPaintInvalidationIfNeeded();
 }
 
 void LayoutObject::setMayNeedPaintInvalidationSubtree() {
   if (mayNeedPaintInvalidationSubtree())
     return;
   m_bitfields.setMayNeedPaintInvalidationSubtree(true);
   setMayNeedPaintInvalidation();
 }
 
 void LayoutObject::setMayNeedPaintInvalidationAnimatedBackgroundImage() {
   if (mayNeedPaintInvalidationAnimatedBackgroundImage())
     return;
   m_bitfields.setMayNeedPaintInvalidationAnimatedBackgroundImage(true);
-  setMayNeedPaintInvalidation();
+  setMayNeedPaintInvalidationWithoutGeometryChange();
 }
 
 void LayoutObject::clearPaintInvalidationFlags() {
   // paintInvalidationStateIsDirty should be kept in sync with the
   // booleans that are cleared below.
 #if DCHECK_IS_ON()
   DCHECK(!shouldCheckForPaintInvalidationRegardlessOfPaintInvalidationState() ||
          paintInvalidationStateIsDirty());
 #endif
   clearShouldDoFullPaintInvalidation();
-  m_bitfields.setChildShouldCheckForPaintInvalidation(false);
   m_bitfields.setMayNeedPaintInvalidation(false);
   m_bitfields.setMayNeedPaintInvalidationSubtree(false);
   m_bitfields.setMayNeedPaintInvalidationAnimatedBackgroundImage(false);
+  m_bitfields.setNeedsPaintOffsetAndVisualRectUpdate(false);
   m_bitfields.setShouldInvalidateSelection(false);
   m_bitfields.setBackgroundChangedSinceLastPaintInvalidation(false);
 }
 
 bool LayoutObject::isAllowedToModifyLayoutTreeStructure(Document& document) {
   return DeprecatedDisableModifyLayoutTreeStructureAsserts::
              canModifyLayoutTreeStateInAnyState() ||
          document.lifecycle().stateAllowsLayoutTreeMutations();
 }
 
@@ skipping 102 matching lines @@
     const blink::LayoutObject* root = object1;
     while (root->parent())
       root = root->parent();
     root->showLayoutTreeAndMark(object1, "*", object2, "-", 0);
   } else {
     WTFLogAlways("%s", "Cannot showLayoutTree. Root is (nil)");
   }
 }
 
 #endif