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28 #include "core/dom/ElementDataCache.h"
30 #include "core/dom/ElementData.h"
34 inline unsigned attributeHash(const Vector<Attribute>& attributes)
36 return StringHasher::hashMemory(attributes.data(), attributes.size() * sizeof(Attribute));
39 inline bool hasSameAttributes(const Vector<Attribute>& attributes, ShareableElementData& elementData)
41 if (attributes.size() != elementData.length())
43 return !memcmp(attributes.data(), elementData.m_attributeArray, attributes.size() * sizeof(Attribute));
46 PassRefPtr<ShareableElementData> ElementDataCache::cachedShareableElementDataWithAttributes(const Vector<Attribute>& attributes)
48 ASSERT(!attributes.isEmpty());
50 ShareableElementDataCache::ValueType* it = m_shareableElementDataCache.add(attributeHash(attributes), 0).storedValue;
52 // FIXME: This prevents sharing when there's a hash collision.
53 if (it->value && !hasSameAttributes(attributes, *it->value))
54 return ShareableElementData::createWithAttributes(attributes);
57 it->value = ShareableElementData::createWithAttributes(attributes);
59 return it->value.get();
62 ElementDataCache::ElementDataCache()
66 ElementDataCache::~ElementDataCache()