Sibling invalidation sets

Source/core/css/invalidation/DescendantInvalidationSet.cpp

Index: Source/core/css/invalidation/DescendantInvalidationSet.cpp
diff --git a/Source/core/css/invalidation/DescendantInvalidationSet.cpp b/Source/core/css/invalidation/DescendantInvalidationSet.cpp
index 6b4a355730a5dd2e354e25ec86e423c602ad7d7d..f48efe020dda9dddf5c50adfec4f769535809cf7 100644
--- a/Source/core/css/invalidation/DescendantInvalidationSet.cpp
+++ b/Source/core/css/invalidation/DescendantInvalidationSet.cpp
@@ -52,7 +52,9 @@ void DescendantInvalidationSet::cacheTracingFlag()
 }
 
 DescendantInvalidationSet::DescendantInvalidationSet()
-    : m_allDescendantsMightBeInvalid(false)
+    : m_maxDirectAdjacentSelectors(1)
+    , m_siblingInvalid(false)
+    , m_allDescendantsMightBeInvalid(false)
     , m_customPseudoInvalid(false)
     , m_treeBoundaryCrossing(false)
     , m_insertionPointCrossing(false)
@@ -98,6 +100,8 @@ bool DescendantInvalidationSet::invalidatesElement(Element& element) const
 
 void DescendantInvalidationSet::combine(const DescendantInvalidationSet& other)
 {
+    m_maxDirectAdjacentSelectors = std::max(m_maxDirectAdjacentSelectors, other.m_maxDirectAdjacentSelectors);
+
     // No longer bother combining data structures, since the whole subtree is deemed invalid.
     if (wholeSubtreeInvalid())
         return;
@@ -107,6 +111,9 @@ void DescendantInvalidationSet::combine(const DescendantInvalidationSet& other)
         return;
     }
 
+    if (other.siblingInvalid())
+        setSiblingInvalid();
+
     if (other.customPseudoInvalid())
         setCustomPseudoInvalid();
 
@@ -135,6 +142,11 @@ void DescendantInvalidationSet::combine(const DescendantInvalidationSet& other)
         for (const auto& attribute : *other.m_attributes)
             addAttribute(attribute);
     }
+
+    if (other.descendants())
+        ensureDescendantInvalidationSet().combine(*other.descendants());
+
+    m_maxDirectAdjacentSelectors = std::max(m_maxDirectAdjacentSelectors, other.maxDirectAdjacentSelectors());
 }
 
 WillBeHeapHashSet<AtomicString>& DescendantInvalidationSet::ensureClassSet()
@@ -165,6 +177,14 @@ WillBeHeapHashSet<AtomicString>& DescendantInvalidationSet::ensureAttributeSet()
     return *m_attributes;
 }
 
+DescendantInvalidationSet& DescendantInvalidationSet::ensureDescendantInvalidationSet()
+{
+    if (!m_descendantInvalidationSet)
+        m_descendantInvalidationSet = DescendantInvalidationSet::create();
+
+    return *m_descendantInvalidationSet;
+}
+
 void DescendantInvalidationSet::addClass(const AtomicString& className)
 {
     if (wholeSubtreeInvalid())
@@ -199,6 +219,7 @@ void DescendantInvalidationSet::setWholeSubtreeInvalid()
         return;
 
     m_allDescendantsMightBeInvalid = true;
+    m_siblingInvalid = false;
     m_customPseudoInvalid = false;
     m_treeBoundaryCrossing = false;
     m_insertionPointCrossing = false;
@@ -206,6 +227,7 @@ void DescendantInvalidationSet::setWholeSubtreeInvalid()
     m_ids = nullptr;
     m_tagNames = nullptr;
     m_attributes = nullptr;
+    m_descendantInvalidationSet = nullptr;
 }
 
 DEFINE_TRACE(DescendantInvalidationSet)