187428 2018-07-06 21:26:24 -0700 SVGAnimationElement is bloated by members of SVGTests 2018-07-06 21:53:57 -0700 1 1 1 Unclassified WebKit SVG WebKit Nightly Build Unspecified Unspecified NEW P2 Normal --- 1 simon.fraser webkit-unassigned sabouhallawa simon.fraser zimmermann oldest_to_newest 1440089 0 simon.fraser 2018-07-06 21:26:24 -0700 SVGAnimationElement inherits from SVGTests, which has: SVGSynchronizableAnimatedProperty<SVGStringListValues> m_requiredFeatures; SVGSynchronizableAnimatedProperty<SVGStringListValues> m_requiredExtensions; SVGSynchronizableAnimatedProperty<SVGStringListValues> m_systemLanguage; I don't know why we could have inline data members for attributes that are probably unspecified on 99.9% of SVG elements. Also, these attributes are not animatable according to spec, so I don't know why they have to use SVGSynchronizableAnimatedProperty. The class layout is very inefficient, because there's padding between each of these data members; 19$ $ ./Tools/Scripts/dump-class-layout -c Release WebCore SVGPathElement +0 <416> SVGPathElement +0 <312> WebCore::SVGGeometryElement WebCore::SVGGeometryElement +0 <304> WebCore::SVGGraphicsElement WebCore::SVGGraphicsElement +0 <160> WebCore::SVGElement WebCore::SVGElement +0 < 96> WebCore::StyledElement WebCore::StyledElement +0 < 96> WebCore::Element WebCore::Element +0 < 80> WebCore::ContainerNode WebCore::ContainerNode +0 < 64> WebCore::Node WebCore::Node +0 < 16> WebCore::EventTarget WebCore::EventTarget +0 < 8> __vtbl_ptr_type * _vptr +8 < 8> WebCore::ScriptWrappable WebCore::ScriptWrappable +8 < 8> JSC::Weak<WebCore::JSDOMObject> m_wrapper +8 < 8> JSC::WeakImpl * m_impl +16 < 4> int m_refCount +20 < 4> uint32_t m_nodeFlags +24 < 8> WebCore::ContainerNode * m_parentNode +32 < 8> WebCore::TreeScope * m_treeScope +40 < 8> WebCore::Node * m_previous +48 < 8> WebCore::Node * m_next +56 < 8> WebCore::Node::DataUnion m_data +64 < 8> WebCore::Node * m_firstChild +72 < 8> WebCore::Node * m_lastChild +80 < 8> WebCore::QualifiedName m_tagName +80 < 8> WTF::RefPtr<WebCore::QualifiedName::QualifiedNameImpl, WTF::DumbPtrTraits<WebCore::QualifiedName::QualifiedNameImpl> > m_impl +80 < 8> WTF::DumbPtrTraits<WebCore::QualifiedName::QualifiedNameImpl>::StorageType m_ptr +88 < 8> WTF::RefPtr<WebCore::ElementData, WTF::DumbPtrTraits<WebCore::ElementData> > m_elementData +88 < 8> WTF::DumbPtrTraits<WebCore::ElementData>::StorageType m_ptr +96 < 16> WebCore::SVGLangSpace WebCore::SVGLangSpace +96 < 8> WTF::AtomicString m_lang +96 < 8> WTF::String m_string +96 < 8> WTF::RefPtr<WTF::StringImpl, WTF::DumbPtrTraits<WTF::StringImpl> > m_impl +96 < 8> WTF::DumbPtrTraits<WTF::StringImpl>::StorageType m_ptr +104 < 8> WTF::AtomicString m_space +104 < 8> WTF::String m_string +104 < 8> WTF::RefPtr<WTF::StringImpl, WTF::DumbPtrTraits<WTF::StringImpl> > m_impl +104 < 8> WTF::DumbPtrTraits<WTF::StringImpl>::StorageType m_ptr +112 < 8> std::__1::unique_ptr<WebCore::SVGElementRareData, std::__1::default_delete<WebCore::SVGElementRareData> > m_svgRareData +112 < 8> std::__1::__compressed_pair<WebCore::SVGElementRareData *, std::__1::default_delete<WebCore::SVGElementRareData> > __ptr_ +112 < 8> std::__1::__compressed_pair_elem<WebCore::SVGElementRareData *, 0, false> std::__1::__compressed_pair_elem<WebCore::SVGElementRareData *, 0, false> +112 < 8> WebCore::SVGElementRareData * __value_ +112 < 1> std::__1::__compressed_pair_elem<std::__1::default_delete<WebCore::SVGElementRareData>, 1, true> std::__1::__compressed_pair_elem<std::__1::default_delete<WebCore::SVGElementRareData>, 1, true> +112 < 1> std::__1::default_delete<WebCore::SVGElementRareData> std::__1::default_delete<WebCore::SVGElementRareData> +120 < 24> WTF::HashSet<WebCore::SVGElement *, WTF::PtrHash<WebCore::SVGElement *>, WTF::HashTraits<WebCore::SVGElement *> > m_elementsWithRelativeLengths +120 < 24> WTF::HashSet<WebCore::SVGElement *, WTF::PtrHash<WebCore::SVGElement *>, WTF::HashTraits<WebCore::SVGElement *> >::HashTableType m_impl +120 < 8> WTF::HashTable<WebCore::SVGElement *, WebCore::SVGElement *, WTF::IdentityExtractor, WTF::PtrHash<WebCore::SVGElement *>, WTF::HashTraits<WebCore::SVGElement *>, WTF::HashTraits<WebCore::SVGElement *> >::ValueType * m_table +128 < 4> unsigned int m_tableSize +132 < 4> unsigned int m_tableSizeMask +136 < 4> unsigned int m_keyCount +140 < 4> unsigned int m_deletedCount +144 < 16> WebCore::SVGSynchronizableAnimatedProperty<WTF::String> m_className +144 < 8> WTF::String value +144 < 8> WTF::RefPtr<WTF::StringImpl, WTF::DumbPtrTraits<WTF::StringImpl> > m_impl +144 < 8> WTF::DumbPtrTraits<WTF::StringImpl>::StorageType m_ptr +152 < 1> bool shouldSynchronize : 1 +152 < 1> bool isValid : 1 +153 < 7> <PADDING: 7 bytes> +160 < 8> WebCore::SVGTransformable WebCore::SVGTransformable +160 < 8> WebCore::SVGLocatable WebCore::SVGLocatable +160 < 8> __vtbl_ptr_type * _vptr +168 < 96> WebCore::SVGTests WebCore::SVGTests +168 < 32> WebCore::SVGSynchronizableAnimatedProperty<WebCore::SVGStringListValues> m_requiredFeatures +168 < 24> WebCore::SVGStringListValues value +168 < 16> WTF::Vector<WTF::String, 0, WTF::CrashOnOverflow, 16> WTF::Vector<WTF::String, 0, WTF::CrashOnOverflow, 16> +168 < 16> WTF::VectorBuffer<WTF::String, 0> WTF::VectorBuffer<WTF::String, 0> +168 < 16> WTF::VectorBufferBase<WTF::String> WTF::VectorBufferBase<WTF::String> +168 < 8> WTF::String * m_buffer +176 < 4> unsigned int m_capacity +180 < 4> unsigned int m_size +184 < 8> const WebCore::QualifiedName & m_attributeName +192 < 1> bool shouldSynchronize : 1 +192 < 1> bool isValid : 1 +361 < 7> <PADDING: 7 bytes> +200 < 32> WebCore::SVGSynchronizableAnimatedProperty<WebCore::SVGStringListValues> m_requiredExtensions +200 < 24> WebCore::SVGStringListValues value +200 < 16> WTF::Vector<WTF::String, 0, WTF::CrashOnOverflow, 16> WTF::Vector<WTF::String, 0, WTF::CrashOnOverflow, 16> +200 < 16> WTF::VectorBuffer<WTF::String, 0> WTF::VectorBuffer<WTF::String, 0> +200 < 16> WTF::VectorBufferBase<WTF::String> WTF::VectorBufferBase<WTF::String> +200 < 8> WTF::String * m_buffer +208 < 4> unsigned int m_capacity +212 < 4> unsigned int m_size +216 < 8> const WebCore::QualifiedName & m_attributeName +224 < 1> bool shouldSynchronize : 1 +224 < 1> bool isValid : 1 +393 < 7> <PADDING: 7 bytes> +232 < 32> WebCore::SVGSynchronizableAnimatedProperty<WebCore::SVGStringListValues> m_systemLanguage +232 < 24> WebCore::SVGStringListValues value +232 < 16> WTF::Vector<WTF::String, 0, WTF::CrashOnOverflow, 16> WTF::Vector<WTF::String, 0, WTF::CrashOnOverflow, 16> +232 < 16> WTF::VectorBuffer<WTF::String, 0> WTF::VectorBuffer<WTF::String, 0> +232 < 16> WTF::VectorBufferBase<WTF::String> WTF::VectorBufferBase<WTF::String> +232 < 8> WTF::String * m_buffer +240 < 4> unsigned int m_capacity +244 < 4> unsigned int m_size +248 < 8> const WebCore::QualifiedName & m_attributeName +256 < 1> bool shouldSynchronize : 1 +256 < 1> bool isValid : 1 +257 < 7> <PADDING: 7 bytes> +264 < 24> WebCore::SVGSynchronizableAnimatedProperty<WebCore::SVGTransformListValues> m_transform +264 < 16> WebCore::SVGTransformListValues value +264 < 16> WTF::Vector<WebCore::SVGTransformValue, 0, WTF::CrashOnOverflow, 2> WTF::Vector<WebCore::SVGTransformValue, 0, WTF::CrashOnOverflow, 2> +264 < 16> WTF::VectorBuffer<WebCore::SVGTransformValue, 0> WTF::VectorBuffer<WebCore::SVGTransformValue, 0> +264 < 16> WTF::VectorBufferBase<WebCore::SVGTransformValue> WTF::VectorBufferBase<WebCore::SVGTransformValue> +264 < 8> WebCore::SVGTransformValue * m_buffer +272 < 4> unsigned int m_capacity +276 < 4> unsigned int m_size +280 < 1> bool shouldSynchronize : 1 +280 < 1> bool isValid : 1 +281 < 7> <PADDING: 7 bytes> +288 < 8> std::__1::unique_ptr<WebCore::AffineTransform, std::__1::default_delete<WebCore::AffineTransform> > m_supplementalTransform +288 < 8> std::__1::__compressed_pair<WebCore::AffineTransform *, std::__1::default_delete<WebCore::AffineTransform> > __ptr_ +288 < 8> std::__1::__compressed_pair_elem<WebCore::AffineTransform *, 0, false> std::__1::__compressed_pair_elem<WebCore::AffineTransform *, 0, false> +288 < 8> WebCore::AffineTransform * __value_ +288 < 1> std::__1::__compressed_pair_elem<std::__1::default_delete<WebCore::AffineTransform>, 1, true> std::__1::__compressed_pair_elem<std::__1::default_delete<WebCore::AffineTransform>, 1, true> +288 < 1> std::__1::default_delete<WebCore::AffineTransform> std::__1::default_delete<WebCore::AffineTransform> +296 < 1> bool m_shouldIsolateBlending +297 < 3> <PADDING: 3 bytes> +300 < 8> WebCore::SVGSynchronizableAnimatedProperty<float> m_pathLength +300 < 4> float value +304 < 1> bool shouldSynchronize : 1 +304 < 1> bool isValid : 1 +305 < 7> <PADDING: 7 bytes> +312 < 8> WebCore::SVGExternalResourcesRequired WebCore::SVGExternalResourcesRequired +312 < 8> __vtbl_ptr_type * _vptr +320 < 8> WTF::CanMakeWeakPtr<WebCore::SVGPathElement> WTF::CanMakeWeakPtr<WebCore::SVGPathElement> +320 < 8> WTF::WeakPtrFactory<WebCore::SVGPathElement> m_weakFactory +320 < 8> WTF::RefPtr<WTF::WeakReference<WebCore::SVGPathElement>, WTF::DumbPtrTraits<WTF::WeakReference<WebCore::SVGPathElement> > > m_ref +320 < 8> WTF::DumbPtrTraits<WTF::WeakReference<WebCore::SVGPathElement> >::StorageType m_ptr +328 < 8> WebCore::SVGSynchronizableAnimatedProperty<float> m_pathLength +328 < 4> float value +332 < 1> bool shouldSynchronize : 1 +332 < 1> bool isValid : 1 +333 < 3> <PADDING: 3 bytes> +336 < 2> WebCore::SVGSynchronizableAnimatedProperty<bool> m_externalResourcesRequired +336 < 1> bool value +337 < 1> bool shouldSynchronize : 1 +337 < 1> bool isValid : 1 +338 < 6> <PADDING: 6 bytes> +344 < 16> WebCore::SVGPathByteStream m_pathByteStream +344 < 16> WebCore::SVGPathByteStream::Data m_data +344 < 16> WTF::VectorBuffer<unsigned char, 0> WTF::VectorBuffer<unsigned char, 0> +344 < 16> WTF::VectorBufferBase<unsigned char> WTF::VectorBufferBase<unsigned char> +344 < 8> unsigned char * m_buffer +352 < 4> unsigned int m_capacity +356 < 4> unsigned int m_size +360 < 16> std::optional<WebCore::Path> m_cachedPath +360 < 16> std::OptionalBase<WebCore::Path> std::OptionalBase<WebCore::Path> +360 < 1> bool init_ +721 < 7> <PADDING: 7 bytes> +368 < 8> std::storage_t<WebCore::Path> storage_ +376 < 32> WebCore::SVGSynchronizableAnimatedProperty<WebCore::SVGPathSegListValues> m_pathSegList +376 < 24> WebCore::SVGPathSegListValues value +376 < 16> WTF::Vector<WTF::RefPtr<WebCore::SVGPathSeg, WTF::DumbPtrTraits<WebCore::SVGPathSeg> >, 0, WTF::CrashOnOverflow, 16> WTF::Vector<WTF::RefPtr<WebCore::SVGPathSeg, WTF::DumbPtrTraits<WebCore::SVGPathSeg> >, 0, WTF::CrashOnOverflow, 16> +376 < 16> WTF::VectorBuffer<WTF::RefPtr<WebCore::SVGPathSeg, WTF::DumbPtrTraits<WebCore::SVGPathSeg> >, 0> WTF::VectorBuffer<WTF::RefPtr<WebCore::SVGPathSeg, WTF::DumbPtrTraits<WebCore::SVGPathSeg> >, 0> +376 < 16> WTF::VectorBufferBase<WTF::RefPtr<WebCore::SVGPathSeg, WTF::DumbPtrTraits<WebCore::SVGPathSeg> > > WTF::VectorBufferBase<WTF::RefPtr<WebCore::SVGPathSeg, WTF::DumbPtrTraits<WebCore::SVGPathSeg> > > +376 < 8> WTF::RefPtr<WebCore::SVGPathSeg, WTF::DumbPtrTraits<WebCore::SVGPathSeg> > * m_buffer +384 < 4> unsigned int m_capacity +388 < 4> unsigned int m_size +392 < 4> WebCore::SVGPathSegRole m_role +772 < 4> <PADDING: 4 bytes> +400 < 1> bool shouldSynchronize : 1 +400 < 1> bool isValid : 1 +401 < 7> <PADDING: 7 bytes> +408 < 1> bool m_isAnimValObserved +409 < 7> <PADDING: 7 bytes> Total byte size: 416 Total pad bytes: 79 Padding percentage: 18.99 % 1440090 1 simon.fraser 2018-07-06 21:27:18 -0700 On nytimes.com, there are 1227 SVGPathElements, which use a total of 510432 bytes, so this adds up. 1440100 2 sabouhallawa 2018-07-06 21:53:57 -0700 I changed the types of the SVGTests members to be non animatable to comply withe the specs in the code refactoring patch https://bugs.webkit.org/show_bug.cgi?id=186751.