hash_functions.h | Explore in Territory

/*
 * Copyright (C) 2005, 2006, 2008 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 THIRD_PARTY_BLINK_RENDERER_PLATFORM_WTF_HASH_FUNCTIONS_H_
#define THIRD_PARTY_BLINK_RENDERER_PLATFORM_WTF_HASH_FUNCTIONS_H_

#include <stdint.h>
#include <type_traits>

#include "base/bit_cast.h"

namespace WTF {

namespace internal {

template <size_t size>
struct IntTypes;
template <>
struct IntTypes<1> { … };
template <>
struct IntTypes<2> { … };
template <>
struct IntTypes<4> { … };
template <>
struct IntTypes<8> { … };

IntHashBits;

// Hash functions for integral and enum types.

// Thomas Wang's 32 Bit Mix Function:
// https://web.archive.org/web/20060507103516/http://www.cris.com/~Ttwang/tech/inthash.htm
inline unsigned HashInt(uint32_t key) { … }

inline unsigned HashInt(uint16_t key16) { … }

inline unsigned HashInt(uint8_t key8) { … }

// Thomas Wang's 64 bit Mix Function:
// https://web.archive.org/web/20060507103516/http://www.cris.com/~Ttwang/tech/inthash.htm
inline unsigned HashInt(uint64_t key) { … }

}  // namespace internal

// Compound integer hash method:
// http://opendatastructures.org/versions/edition-0.1d/ods-java/node33.html#SECTION00832000000000000000
inline unsigned HashInts(unsigned key1, unsigned key2) { … }

template <typename T>
unsigned HashInt(T key) { … }

template <typename T>
unsigned HashFloat(T key) { … }

template <typename T>
bool FloatEqualForHash(T a, T b) { … }

template <typename T>
unsigned HashPointer(T* key) { … }

// Useful compounding hash functions.
inline void AddIntToHash(unsigned& hash, unsigned key) { … }

inline void AddFloatToHash(unsigned& hash, float value) { … }

}  // namespace WTF

#endif  // THIRD_PARTY_BLINK_RENDERER_PLATFORM_WTF_HASH_FUNCTIONS_H_
chromium/third_party/blink/renderer/platform/wtf/hash_functions.h
