Use the invalidation tree walk for all class mutations, not just those that support

Source/core/css/RuleFeature.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 2004-2005 Allan Sandfeld Jensen (kde@carewolf.com)
  * Copyright (C) 2006, 2007 Nicholas Shanks (webkit@nickshanks.com)
  * Copyright (C) 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012 Apple Inc. All rights reserved.
  * Copyright (C) 2007 Alexey Proskuryakov <ap@webkit.org>
  * Copyright (C) 2007, 2008 Eric Seidel <eric@webkit.org>
  * Copyright (C) 2008, 2009 Torch Mobile Inc. All rights reserved. (http://www.torchmobile.com/)
  * Copyright (c) 2011, Code Aurora Forum. All rights reserved.
  * Copyright (C) Research In Motion Limited 2011. All rights reserved.
@@ skipping 190 matching lines @@
         collectionMode = ProcessClasses;
     collectFeaturesFromSelector(ruleData.selector(), metadata, collectionMode);
     m_metadata.add(metadata);
 
     if (metadata.foundSiblingSelector)
         siblingRules.append(RuleFeature(ruleData.rule(), ruleData.selectorIndex(), ruleData.hasDocumentSecurityOrigin()));
     if (ruleData.containsUncommonAttributeSelector())
         uncommonAttributeRules.append(RuleFeature(ruleData.rule(), ruleData.selectorIndex(), ruleData.hasDocumentSecurityOrigin()));
 }
 
-bool RuleFeatureSet::classInvalidationRequiresSubtreeRecalc(const AtomicString& className)
-{
-    DescendantInvalidationSet* set = m_classInvalidationSets.get(className);
-    return set && set->wholeSubtreeInvalid();
-}
-
 DescendantInvalidationSet& RuleFeatureSet::ensureClassInvalidationSet(const AtomicString& className)
 {
     InvalidationSetMap::AddResult addResult = m_classInvalidationSets.add(className, nullptr);
     if (addResult.isNewEntry)
         addResult.storedValue->value = DescendantInvalidationSet::create();
     return *addResult.storedValue->value;
 }
 
 void RuleFeatureSet::collectFeaturesFromSelector(const CSSSelector& selector)
 {
@@ skipping 77 matching lines @@
 
 void RuleFeatureSet::clear()
 {
     m_metadata.clear();
     siblingRules.clear();
     uncommonAttributeRules.clear();
 }
 
 void RuleFeatureSet::scheduleStyleInvalidationForClassChange(const SpaceSplitString& changedClasses, Element* element)
 {
-    if (computeInvalidationSetsForClassChange(changedClasses, element)) {
-        // FIXME: remove eager calls to setNeedsStyleRecalc here, and instead reuse the invalidation tree walk.
-        // This code remains for now out of conservatism about avoiding performance regressions before TargetedStyleRecalc is launched.
-        element->setNeedsStyleRecalc(SubtreeStyleChange);
+    unsigned changedSize = changedClasses.size();
+    for (unsigned i = 0; i < changedSize; ++i) {
+        addClassToInvalidationSet(changedClasses[i], element);
     }
 }
 
 void RuleFeatureSet::scheduleStyleInvalidationForClassChange(const SpaceSplitString& oldClasses, const SpaceSplitString& newClasses, Element* element)
 {
-    if (computeInvalidationSetsForClassChange(oldClasses, newClasses, element)) {
-        // FIXME: remove eager calls to setNeedsStyleRecalc here, and instead reuse the invalidation tree walk.
-        // This code remains for now out of conservatism about avoiding performance regressions before TargetedStyleRecalc is launched.
-        element->setNeedsStyleRecalc(SubtreeStyleChange);
-    }
-}
-
-bool RuleFeatureSet::computeInvalidationSetsForClassChange(const SpaceSplitString& changedClasses, Element* element)
-{
-    unsigned changedSize = changedClasses.size();
-    for (unsigned i = 0; i < changedSize; ++i) {
-        if (classInvalidationRequiresSubtreeRecalc(changedClasses[i]))
-            return true;
-        addClassToInvalidationSet(changedClasses[i], element);
-    }
-    return false;
-}
-
-bool RuleFeatureSet::computeInvalidationSetsForClassChange(const SpaceSplitString& oldClasses, const SpaceSplitString& newClasses, Element* element)
-{
     if (!oldClasses.size())
-        return computeInvalidationSetsForClassChange(newClasses, element);
+        scheduleStyleInvalidationForClassChange(newClasses, element);
 
     // Class vectors tend to be very short. This is faster than using a hash table.
     BitVector remainingClassBits;
     remainingClassBits.ensureSize(oldClasses.size());
 
     for (unsigned i = 0; i < newClasses.size(); ++i) {
         bool found = false;
         for (unsigned j = 0; j < oldClasses.size(); ++j) {
             if (newClasses[i] == oldClasses[j]) {
                 // Mark each class that is still in the newClasses so we can skip doing
                 // an n^2 search below when looking for removals. We can't break from
                 // this loop early since a class can appear more than once.
                 remainingClassBits.quickSet(j);
                 found = true;
             }
         }
         // Class was added.
-        if (!found) {
-            if (classInvalidationRequiresSubtreeRecalc(newClasses[i]))
-                return true;
+        if (!found)
             addClassToInvalidationSet(newClasses[i], element);
-        }
     }
 
     for (unsigned i = 0; i < oldClasses.size(); ++i) {
         if (remainingClassBits.quickGet(i))
             continue;
-
         // Class was removed.
-        if (classInvalidationRequiresSubtreeRecalc(oldClasses[i]))
-            return true;
         addClassToInvalidationSet(oldClasses[i], element);
     }
-    return false;
 }
 
 void RuleFeatureSet::addClassToInvalidationSet(const AtomicString& className, Element* element)
 {
     if (RefPtr<DescendantInvalidationSet> invalidationSet = m_classInvalidationSets.get(className)) {
         ensurePendingInvalidationList(element).append(invalidationSet);
         element->setNeedsStyleInvalidation();
     }
 }
 
 RuleFeatureSet::InvalidationList& RuleFeatureSet::ensurePendingInvalidationList(Element* element)
 {
     PendingInvalidationMap::AddResult addResult = m_pendingInvalidationMap.add(element, nullptr);
     if (addResult.isNewEntry)
         addResult.storedValue->value = adoptPtr(new InvalidationList);
     return *addResult.storedValue->value;
 }
 
 void RuleFeatureSet::computeStyleInvalidation(Document& document)
 {
     Vector<AtomicString> invalidationClasses;
     if (Element* documentElement = document.documentElement()) {
         if (documentElement->childNeedsStyleInvalidation()) {
             invalidateStyleForClassChange(documentElement, invalidationClasses, false);
         }
     }
     document.clearChildNeedsStyleInvalidation();
+    document.clearNeedsStyleInvalidation();
     m_pendingInvalidationMap.clear();
 }
 
 bool RuleFeatureSet::invalidateStyleForClassChangeOnChildren(Element* element, Vector<AtomicString>& invalidationClasses, bool foundInvalidationSet)
 {
     bool someChildrenNeedStyleRecalc = false;
     for (ShadowRoot* root = element->youngestShadowRoot(); root; root = root->olderShadowRoot()) {
         for (Element* child = ElementTraversal::firstWithin(*root); child; child = ElementTraversal::nextSibling(*child)) {
             bool childRecalced = invalidateStyleForClassChange(child, invalidationClasses, foundInvalidationSet);
             someChildrenNeedStyleRecalc = someChildrenNeedStyleRecalc || childRecalced;
         }
     }
     for (Element* child = ElementTraversal::firstWithin(*element); child; child = ElementTraversal::nextSibling(*child)) {
         bool childRecalced = invalidateStyleForClassChange(child, invalidationClasses, foundInvalidationSet);
         someChildrenNeedStyleRecalc = someChildrenNeedStyleRecalc || childRecalced;
     }
     return someChildrenNeedStyleRecalc;
 }
 
 bool RuleFeatureSet::invalidateStyleForClassChange(Element* element, Vector<AtomicString>& invalidationClasses, bool foundInvalidationSet)
 {
     bool thisElementNeedsStyleRecalc = false;
     int oldSize = invalidationClasses.size();
-
     if (element->needsStyleInvalidation()) {
-        InvalidationList* invalidationList = m_pendingInvalidationMap.get(element);
-        ASSERT(invalidationList);
-        // FIXME: it's really only necessary to clone the render style for this element, not full style recalc.
-        thisElementNeedsStyleRecalc = true;
-        foundInvalidationSet = true;
-        for (InvalidationList::const_iterator it = invalidationList->begin(); it != invalidationList->end(); ++it) {
-            if ((*it)->wholeSubtreeInvalid()) {
-                element->setNeedsStyleRecalc(SubtreeStyleChange);
-                // Even though we have set needsStyleRecalc on the whole subtree, we need to keep walking over the subtree
-                // in order to clear the invalidation dirty bits on all elements.
-                // FIXME: we can optimize this by having a dedicated function that just traverses the tree and removes the dirty bits,
-                // without checking classes etc.
-                break;
+        if (InvalidationList* invalidationList = m_pendingInvalidationMap.get(element)) {
+            // FIXME: it's really only necessary to clone the render style for this element, not full style recalc.
+            thisElementNeedsStyleRecalc = true;
+            foundInvalidationSet = true;
+            for (InvalidationList::const_iterator it = invalidationList->begin(); it != invalidationList->end(); ++it) {
+                if ((*it)->wholeSubtreeInvalid()) {
+                    element->setNeedsStyleRecalc(SubtreeStyleChange);
+                    // Even though we have set needsStyleRecalc on the whole subtree, we need to keep walking over the subtree
+                    // in order to clear the invalidation dirty bits on all elements.
+                    // FIXME: we can optimize this by having a dedicated function that just traverses the tree and removes the dirty bits,
+                    // without checking classes etc.
+                    break;
+                }
+                (*it)->getClasses(invalidationClasses);
             }
-            (*it)->getClasses(invalidationClasses);
         }
     }
 
     if (element->hasClass()) {
         const SpaceSplitString& classNames = element->classNames();
         for (Vector<AtomicString>::const_iterator it = invalidationClasses.begin(); it != invalidationClasses.end(); ++it) {
             if (classNames.contains(*it)) {
                 thisElementNeedsStyleRecalc = true;
                 break;
             }
@@ skipping 16 matching lines @@
     }
 
     invalidationClasses.remove(oldSize, invalidationClasses.size() - oldSize);
     element->clearChildNeedsStyleInvalidation();
     element->clearNeedsStyleInvalidation();
 
     return thisElementNeedsStyleRecalc;
 }
 
 } // namespace WebCore