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Diffstat (limited to 'Source/JavaScriptCore/wtf/HashTraits.h')
-rw-r--r-- | Source/JavaScriptCore/wtf/HashTraits.h | 171 |
1 files changed, 0 insertions, 171 deletions
diff --git a/Source/JavaScriptCore/wtf/HashTraits.h b/Source/JavaScriptCore/wtf/HashTraits.h deleted file mode 100644 index 10f14d1af..000000000 --- a/Source/JavaScriptCore/wtf/HashTraits.h +++ /dev/null @@ -1,171 +0,0 @@ -/* - * Copyright (C) 2005, 2006, 2007, 2008, 2011 Apple Inc. All rights reserved. - * - * This library is free software; you can redistribute it and/or - * modify it under the terms of the GNU Library General Public - * License as published by the Free Software Foundation; either - * version 2 of the License, or (at your option) any later version. - * - * This library is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU - * Library General Public License for more details. - * - * You should have received a copy of the GNU Library General Public License - * along with this library; see the file COPYING.LIB. If not, write to - * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, - * Boston, MA 02110-1301, USA. - * - */ - -#ifndef WTF_HashTraits_h -#define WTF_HashTraits_h - -#include <wtf/HashFunctions.h> -#include <wtf/StdLibExtras.h> -#include <wtf/TypeTraits.h> -#include <utility> -#include <limits> - -namespace WTF { - - class String; - - template<typename T> class OwnPtr; - template<typename T> class PassOwnPtr; - - using std::pair; - using std::make_pair; - - template<typename T> struct HashTraits; - - template<bool isInteger, typename T> struct GenericHashTraitsBase; - - template<typename T> struct GenericHashTraitsBase<false, T> { - static const bool emptyValueIsZero = false; - static const bool needsDestruction = true; - static const int minimumTableSize = 64; - }; - - // Default integer traits disallow both 0 and -1 as keys (max value instead of -1 for unsigned). - template<typename T> struct GenericHashTraitsBase<true, T> : GenericHashTraitsBase<false, T> { - static const bool emptyValueIsZero = true; - static const bool needsDestruction = false; - static void constructDeletedValue(T& slot) { slot = static_cast<T>(-1); } - static bool isDeletedValue(T value) { return value == static_cast<T>(-1); } - }; - - template<typename T> struct GenericHashTraits : GenericHashTraitsBase<IsInteger<T>::value, T> { - typedef T TraitType; - typedef T EmptyValueType; - - static T emptyValue() { return T(); } - - // Type for functions that take ownership, such as add. - // The store function either not be called or called once to store something passed in. - // The value passed to the store function will be either PassInType or PassInType&. - typedef const T& PassInType; - static void store(const T& value, T& storage) { storage = value; } - - // Type for return value of functions that transfer ownership, such as take. - typedef T PassOutType; - static PassOutType passOut(const T& value) { return value; } - - // Type for return value of functions that do not transfer ownership, such as get. - // FIXME: We could change this type to const T& for better performance if we figured out - // a way to handle the return value from emptyValue, which is a temporary. - typedef T PeekType; - static PeekType peek(const T& value) { return value; } - }; - - template<typename T> struct HashTraits : GenericHashTraits<T> { }; - - template<typename T> struct FloatHashTraits : GenericHashTraits<T> { - static const bool needsDestruction = false; - static T emptyValue() { return std::numeric_limits<T>::infinity(); } - static void constructDeletedValue(T& slot) { slot = -std::numeric_limits<T>::infinity(); } - static bool isDeletedValue(T value) { return value == -std::numeric_limits<T>::infinity(); } - }; - - template<> struct HashTraits<float> : FloatHashTraits<float> { }; - template<> struct HashTraits<double> : FloatHashTraits<double> { }; - - // Default unsigned traits disallow both 0 and max as keys -- use these traits to allow zero and disallow max - 1. - template<typename T> struct UnsignedWithZeroKeyHashTraits : GenericHashTraits<T> { - static const bool emptyValueIsZero = false; - static const bool needsDestruction = false; - static T emptyValue() { return std::numeric_limits<T>::max(); } - static void constructDeletedValue(T& slot) { slot = std::numeric_limits<T>::max() - 1; } - static bool isDeletedValue(T value) { return value == std::numeric_limits<T>::max() - 1; } - }; - - template<typename P> struct HashTraits<P*> : GenericHashTraits<P*> { - static const bool emptyValueIsZero = true; - static const bool needsDestruction = false; - static void constructDeletedValue(P*& slot) { slot = reinterpret_cast<P*>(-1); } - static bool isDeletedValue(P* value) { return value == reinterpret_cast<P*>(-1); } - }; - - template<typename T> struct SimpleClassHashTraits : GenericHashTraits<T> { - static const bool emptyValueIsZero = true; - static void constructDeletedValue(T& slot) { new (NotNull, &slot) T(HashTableDeletedValue); } - static bool isDeletedValue(const T& value) { return value.isHashTableDeletedValue(); } - }; - - template<typename P> struct HashTraits<OwnPtr<P> > : SimpleClassHashTraits<OwnPtr<P> > { - typedef std::nullptr_t EmptyValueType; - - static EmptyValueType emptyValue() { return nullptr; } - - typedef PassOwnPtr<P> PassInType; - static void store(PassOwnPtr<P> value, OwnPtr<P>& storage) { storage = value; } - - typedef PassOwnPtr<P> PassOutType; - static PassOwnPtr<P> passOut(OwnPtr<P>& value) { return value.release(); } - static PassOwnPtr<P> passOut(std::nullptr_t) { return nullptr; } - - typedef typename OwnPtr<P>::PtrType PeekType; - static PeekType peek(const OwnPtr<P>& value) { return value.get(); } - static PeekType peek(std::nullptr_t) { return 0; } - }; - - template<typename P> struct HashTraits<RefPtr<P> > : SimpleClassHashTraits<RefPtr<P> > { - typedef PassRefPtr<P> PassInType; - static void store(PassRefPtr<P> value, RefPtr<P>& storage) { storage = value; } - - // FIXME: We should change PassOutType to PassRefPtr for better performance. - // FIXME: We should consider changing PeekType to a raw pointer for better performance, - // but then callers won't need to call get; doing so will require updating many call sites. - }; - - template<> struct HashTraits<String> : SimpleClassHashTraits<String> { }; - - // special traits for pairs, helpful for their use in HashMap implementation - - template<typename FirstTraitsArg, typename SecondTraitsArg> - struct PairHashTraits : GenericHashTraits<pair<typename FirstTraitsArg::TraitType, typename SecondTraitsArg::TraitType> > { - typedef FirstTraitsArg FirstTraits; - typedef SecondTraitsArg SecondTraits; - typedef pair<typename FirstTraits::TraitType, typename SecondTraits::TraitType> TraitType; - typedef pair<typename FirstTraits::EmptyValueType, typename SecondTraits::EmptyValueType> EmptyValueType; - - static const bool emptyValueIsZero = FirstTraits::emptyValueIsZero && SecondTraits::emptyValueIsZero; - static EmptyValueType emptyValue() { return make_pair(FirstTraits::emptyValue(), SecondTraits::emptyValue()); } - - static const bool needsDestruction = FirstTraits::needsDestruction || SecondTraits::needsDestruction; - - static const int minimumTableSize = FirstTraits::minimumTableSize; - - static void constructDeletedValue(TraitType& slot) { FirstTraits::constructDeletedValue(slot.first); } - static bool isDeletedValue(const TraitType& value) { return FirstTraits::isDeletedValue(value.first); } - }; - - template<typename First, typename Second> - struct HashTraits<pair<First, Second> > : public PairHashTraits<HashTraits<First>, HashTraits<Second> > { }; - -} // namespace WTF - -using WTF::HashTraits; -using WTF::PairHashTraits; - -#endif // WTF_HashTraits_h |