1 /* 2 * Copyright (C) 1999 Lars Knoll (knoll (at) kde.org) 3 * Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011 Apple Inc. All rights reserved. 4 * Copyright (C) 2013 Google Inc. All rights reserved. 5 * 6 * This library is free software; you can redistribute it and/or 7 * modify it under the terms of the GNU Library General Public 8 * License as published by the Free Software Foundation; either 9 * version 2 of the License, or (at your option) any later version. 10 * 11 * This library is distributed in the hope that it will be useful, 12 * but WITHOUT ANY WARRANTY; without even the implied warranty of 13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 14 * Library General Public License for more details. 15 * 16 * You should have received a copy of the GNU Library General Public License 17 * along with this library; see the file COPYING.LIB. If not, write to 18 * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, 19 * Boston, MA 02110-1301, USA. 20 * 21 */ 22 23 #ifndef MatchedPropertiesCache_h 24 #define MatchedPropertiesCache_h 25 26 #include "core/css/StylePropertySet.h" 27 #include "core/css/resolver/MatchResult.h" 28 #include "platform/Timer.h" 29 #include "platform/heap/Handle.h" 30 #include "wtf/Forward.h" 31 #include "wtf/HashMap.h" 32 #include "wtf/Noncopyable.h" 33 34 namespace blink { 35 36 class RenderStyle; 37 class StyleResolverState; 38 39 class CachedMatchedProperties FINAL : public NoBaseWillBeGarbageCollectedFinalized<CachedMatchedProperties> { 40 41 public: 42 WillBeHeapVector<MatchedProperties> matchedProperties; 43 MatchRanges ranges; 44 RefPtr<RenderStyle> renderStyle; 45 RefPtr<RenderStyle> parentRenderStyle; 46 47 void set(const RenderStyle*, const RenderStyle* parentStyle, const MatchResult&); 48 void clear(); 49 void trace(Visitor* visitor) { visitor->trace(matchedProperties); } 50 }; 51 52 // Specialize the HashTraits for CachedMatchedProperties to check for dead 53 // entries in the MatchedPropertiesCache. 54 #if ENABLE(OILPAN) 55 struct CachedMatchedPropertiesHashTraits : HashTraits<Member<CachedMatchedProperties> > { 56 static const WTF::WeakHandlingFlag weakHandlingFlag = WTF::WeakHandlingInCollections; 57 static bool traceInCollection(Visitor*, Member<CachedMatchedProperties>&, WTF::ShouldWeakPointersBeMarkedStrongly); 58 }; 59 #endif 60 61 class MatchedPropertiesCache { 62 DISALLOW_ALLOCATION(); 63 WTF_MAKE_NONCOPYABLE(MatchedPropertiesCache); 64 public: 65 MatchedPropertiesCache(); 66 67 const CachedMatchedProperties* find(unsigned hash, const StyleResolverState&, const MatchResult&); 68 void add(const RenderStyle*, const RenderStyle* parentStyle, unsigned hash, const MatchResult&); 69 70 void clear(); 71 void clearViewportDependent(); 72 73 static bool isCacheable(const Element*, const RenderStyle*, const RenderStyle* parentStyle); 74 75 void trace(Visitor*); 76 77 private: 78 #if ENABLE(OILPAN) 79 typedef HeapHashMap<unsigned, Member<CachedMatchedProperties>, DefaultHash<unsigned>::Hash, HashTraits<unsigned>, CachedMatchedPropertiesHashTraits > Cache; 80 #else 81 // Every N additions to the matched declaration cache trigger a sweep where entries holding 82 // the last reference to a style declaration are garbage collected. 83 void sweep(Timer<MatchedPropertiesCache>*); 84 85 unsigned m_additionsSinceLastSweep; 86 87 typedef HashMap<unsigned, OwnPtr<CachedMatchedProperties> > Cache; 88 Timer<MatchedPropertiesCache> m_sweepTimer; 89 #endif 90 Cache m_cache; 91 }; 92 93 } 94 95 #endif 96
