Avoid traversing all custom properties in Styleable::updateCSSTransit…

…ions when not needed

https://bugs.webkit.org/show_bug.cgi?id=267536
rdar://121002539

Reviewed by Antoine Quint.

* Source/WebCore/css/CSSCustomPropertyValue.cpp:
(WebCore::CSSCustomPropertyValue::isAnimatable const):

Factor into a function.

* Source/WebCore/css/CSSCustomPropertyValue.h:
* Source/WebCore/rendering/style/StyleCustomPropertyData.cpp:
(WebCore::StyleCustomPropertyData::StyleCustomPropertyData):
(WebCore::StyleCustomPropertyData::set):

Check if the newly set property is animatable.

(WebCore::StyleCustomPropertyData::size const): Deleted.
* Source/WebCore/rendering/style/StyleCustomPropertyData.h:
(WebCore::StyleCustomPropertyData::size const):
(WebCore::StyleCustomPropertyData::mayHaveAnimatableProperties const):
* Source/WebCore/style/Styleable.cpp:
(WebCore::Styleable::updateCSSTransitions const):

Bail out if before traversing if we already know the properties are not animatable.

Canonical link: https://commits.webkit.org/273045@main

Source/WebCore/css/CSSCustomPropertyValue.cpp

@@ -187,4 +187,9 @@ bool CSSCustomPropertyValue::isCurrentColor() const
     return token.id() == CSSValueCurrentcolor;
 }
 
+bool CSSCustomPropertyValue::isAnimatable() const
+{
+    return std::holds_alternative<SyntaxValue>(m_value) || std::holds_alternative<SyntaxValueList>(m_value);
+}
+
 }

Source/WebCore/css/CSSCustomPropertyValue.h

@@ -97,6 +97,7 @@ class CSSCustomPropertyValue final : public CSSValue {
     bool isInherit() const { return std::holds_alternative<CSSValueID>(m_value) && std::get<CSSValueID>(m_value) == CSSValueInherit; }
     bool isCurrentColor() const;
     bool containsCSSWideKeyword() const;
+    bool isAnimatable() const;
 
     const VariantValue& value() const { return m_value; }
 

Source/WebCore/rendering/style/StyleCustomPropertyData.cpp

@@ -32,6 +32,7 @@ static constexpr auto maximumAncestorCount = 4;
 
 StyleCustomPropertyData::StyleCustomPropertyData(const StyleCustomPropertyData& other)
     : m_size(other.m_size)
+    , m_mayHaveAnimatableProperties(other.m_mayHaveAnimatableProperties)
 {
     auto shouldReferenceAsParentValues = [&] {
         // Always reference the root style since it likely gets shared a lot.
@@ -81,6 +82,8 @@ void StyleCustomPropertyData::set(const AtomString& name, Ref<const CSSCustomPro
         return !existing || !existing->equals(value);
     }());
 
+    m_mayHaveAnimatableProperties = m_mayHaveAnimatableProperties || value->isAnimatable();
+
     auto addResult = m_ownValues.set(name, WTFMove(value));
 
     bool isNewProperty = addResult.isNewEntry && (!m_parentValues || !m_parentValues->get(name));
@@ -168,9 +171,4 @@ AtomString StyleCustomPropertyData::findKeyAtIndex(unsigned index) const
     return key;
 }
 
-unsigned StyleCustomPropertyData::size() const
-{
-    return m_size;
-}
-
 } // namespace WebCore

Source/WebCore/rendering/style/StyleCustomPropertyData.h

@@ -44,7 +44,8 @@ class StyleCustomPropertyData : public RefCounted<StyleCustomPropertyData> {
     const CSSCustomPropertyValue* get(const AtomString&) const;
     void set(const AtomString&, Ref<const CSSCustomPropertyValue>&&);
 
-    unsigned size() const;
+    unsigned size() const { return m_size; }
+    bool mayHaveAnimatableProperties() const { return m_mayHaveAnimatableProperties; }
 
     void forEach(const Function<IterationStatus(const KeyValuePair<AtomString, RefPtr<const CSSCustomPropertyValue>>&)>&) const;
     AtomString findKeyAtIndex(unsigned) const;
@@ -59,6 +60,7 @@ class StyleCustomPropertyData : public RefCounted<StyleCustomPropertyData> {
     CustomPropertyValueMap m_ownValues;
     unsigned m_size { 0 };
     unsigned m_ancestorCount { 0 };
+    bool m_mayHaveAnimatableProperties { false };
 #if ASSERT_ENABLED
     mutable bool m_hasChildren { false };
 #endif

Source/WebCore/style/Styleable.cpp

@@ -729,11 +729,12 @@ void Styleable::updateCSSTransitions(const RenderStyle& currentStyle, const Rend
 
         transitionCustomProperties.clear();
         auto gatherAnimatableCustomProperties = [&](const StyleCustomPropertyData& customPropertyData) {
+            if (!customPropertyData.mayHaveAnimatableProperties())
+                return;
+
             customPropertyData.forEach([&](auto& customPropertyAndValuePair) {
                 auto [customProperty, customPropertyValue] = customPropertyAndValuePair;
-                auto& variantValue = customPropertyValue->value();
-                if (std::holds_alternative<CSSCustomPropertyValue::SyntaxValue>(variantValue)
-                    || std::holds_alternative<CSSCustomPropertyValue::SyntaxValueList>(variantValue))
+                if (customPropertyValue->isAnimatable())
                     transitionCustomProperties.add(customProperty);
                 return IterationStatus::Continue;
             });