| /* |
| * Copyright (C) 2012, 2013 Apple Inc. All Rights Reserved. |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions |
| * are met: |
| * 1. Redistributions of source code must retain the above copyright |
| * notice, this list of conditions and the following disclaimer. |
| * 2. Redistributions in binary form must reproduce the above copyright |
| * notice, this list of conditions and the following disclaimer in the |
| * documentation and/or other materials provided with the distribution. |
| * |
| * THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``AS IS'' AND ANY |
| * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
| * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR |
| * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE COMPUTER, INC. OR |
| * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, |
| * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, |
| * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR |
| * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY |
| * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
| * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE |
| * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| * |
| */ |
| |
| #include "core/dom/ElementDataCache.h" |
| |
| #include "core/dom/ElementData.h" |
| |
| namespace blink { |
| |
| inline unsigned attributeHash(const Vector<Attribute>& attributes) |
| { |
| return StringHasher::hashMemory(attributes.data(), attributes.size() * sizeof(Attribute)); |
| } |
| |
| inline bool hasSameAttributes(const Vector<Attribute>& attributes, ShareableElementData& elementData) |
| { |
| if (attributes.size() != elementData.attributes().size()) |
| return false; |
| return !memcmp(attributes.data(), elementData.m_attributeArray, attributes.size() * sizeof(Attribute)); |
| } |
| |
| ShareableElementData* ElementDataCache::cachedShareableElementDataWithAttributes(const Vector<Attribute>& attributes) |
| { |
| DCHECK(!attributes.isEmpty()); |
| |
| ShareableElementDataCache::ValueType* it = m_shareableElementDataCache.add(attributeHash(attributes), nullptr).storedValue; |
| |
| // FIXME: This prevents sharing when there's a hash collision. |
| if (it->value && !hasSameAttributes(attributes, *it->value)) |
| return ShareableElementData::createWithAttributes(attributes); |
| |
| if (!it->value) |
| it->value = ShareableElementData::createWithAttributes(attributes); |
| |
| return it->value.get(); |
| } |
| |
| ElementDataCache::ElementDataCache() |
| { |
| } |
| |
| DEFINE_TRACE(ElementDataCache) |
| { |
| visitor->trace(m_shareableElementDataCache); |
| } |
| |
| } // namespace blink |