1 /* 2 * Copyright (C) 2008 Apple Inc. All rights reserved. 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions 6 * are met: 7 * 1. Redistributions of source code must retain the above copyright 8 * notice, this list of conditions and the following disclaimer. 9 * 2. Redistributions in binary form must reproduce the above copyright 10 * notice, this list of conditions and the following disclaimer in the 11 * documentation and/or other materials provided with the distribution. 12 * 13 * THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``AS IS'' AND ANY 14 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 15 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 16 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE COMPUTER, INC. OR 17 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 18 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, 19 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR 20 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY 21 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 23 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 24 */ 25 26 #ifndef StructureTransitionTable_h 27 #define StructureTransitionTable_h 28 29 #include "UString.h" 30 #include <wtf/HashFunctions.h> 31 #include <wtf/HashMap.h> 32 #include <wtf/HashTraits.h> 33 #include <wtf/RefPtr.h> 34 35 namespace JSC { 36 37 class Structure; 38 39 struct StructureTransitionTableHash { 40 typedef std::pair<RefPtr<UString::Rep>, std::pair<unsigned, JSCell*> > Key; hashStructureTransitionTableHash41 static unsigned hash(const Key& p) 42 { 43 return p.first->computedHash(); 44 } 45 equalStructureTransitionTableHash46 static bool equal(const Key& a, const Key& b) 47 { 48 return a == b; 49 } 50 51 static const bool safeToCompareToEmptyOrDeleted = true; 52 }; 53 54 struct StructureTransitionTableHashTraits { 55 typedef WTF::HashTraits<RefPtr<UString::Rep> > FirstTraits; 56 typedef WTF::GenericHashTraits<unsigned> SecondFirstTraits; 57 typedef WTF::GenericHashTraits<JSCell*> SecondSecondTraits; 58 typedef std::pair<FirstTraits::TraitType, std::pair<SecondFirstTraits::TraitType, SecondSecondTraits::TraitType> > TraitType; 59 60 static const bool emptyValueIsZero = FirstTraits::emptyValueIsZero && SecondFirstTraits::emptyValueIsZero && SecondSecondTraits::emptyValueIsZero; emptyValueStructureTransitionTableHashTraits61 static TraitType emptyValue() { return std::make_pair(FirstTraits::emptyValue(), std::make_pair(SecondFirstTraits::emptyValue(), SecondSecondTraits::emptyValue())); } 62 63 static const bool needsDestruction = FirstTraits::needsDestruction || SecondFirstTraits::needsDestruction || SecondSecondTraits::needsDestruction; 64 constructDeletedValueStructureTransitionTableHashTraits65 static void constructDeletedValue(TraitType& slot) { FirstTraits::constructDeletedValue(slot.first); } isDeletedValueStructureTransitionTableHashTraits66 static bool isDeletedValue(const TraitType& value) { return FirstTraits::isDeletedValue(value.first); } 67 }; 68 69 typedef HashMap<StructureTransitionTableHash::Key, Structure*, StructureTransitionTableHash, StructureTransitionTableHashTraits> StructureTransitionTable; 70 71 } // namespace JSC 72 73 #endif // StructureTransitionTable_h 74