qemu-e2k/include/qemu/xxhash.h

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/*
* xxHash - Fast Hash algorithm
* Copyright (C) 2012-2016, Yann Collet
*
* BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php)
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are
* met:
*
* + Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* + 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 THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "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 THE COPYRIGHT
* OWNER 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.
*
* You can contact the author at :
* - xxHash source repository : https://github.com/Cyan4973/xxHash
*/
#ifndef QEMU_XXHASH_H
#define QEMU_XXHASH_H
#include "qemu/bitops.h"
#define PRIME32_1 2654435761U
#define PRIME32_2 2246822519U
#define PRIME32_3 3266489917U
#define PRIME32_4 668265263U
#define PRIME32_5 374761393U
#define QEMU_XXHASH_SEED 1
/*
* xxhash32, customized for input variables that are not guaranteed to be
* contiguous in memory.
*/
static inline uint32_t
qemu_xxhash7(uint64_t ab, uint64_t cd, uint32_t e, uint32_t f, uint32_t g)
{
uint32_t v1 = QEMU_XXHASH_SEED + PRIME32_1 + PRIME32_2;
uint32_t v2 = QEMU_XXHASH_SEED + PRIME32_2;
uint32_t v3 = QEMU_XXHASH_SEED + 0;
uint32_t v4 = QEMU_XXHASH_SEED - PRIME32_1;
uint32_t a = ab;
uint32_t b = ab >> 32;
uint32_t c = cd;
uint32_t d = cd >> 32;
uint32_t h32;
v1 += a * PRIME32_2;
v1 = rol32(v1, 13);
v1 *= PRIME32_1;
v2 += b * PRIME32_2;
v2 = rol32(v2, 13);
v2 *= PRIME32_1;
v3 += c * PRIME32_2;
v3 = rol32(v3, 13);
v3 *= PRIME32_1;
v4 += d * PRIME32_2;
v4 = rol32(v4, 13);
v4 *= PRIME32_1;
h32 = rol32(v1, 1) + rol32(v2, 7) + rol32(v3, 12) + rol32(v4, 18);
h32 += 28;
h32 += e * PRIME32_3;
h32 = rol32(h32, 17) * PRIME32_4;
h32 += f * PRIME32_3;
h32 = rol32(h32, 17) * PRIME32_4;
h32 += g * PRIME32_3;
h32 = rol32(h32, 17) * PRIME32_4;
h32 ^= h32 >> 15;
h32 *= PRIME32_2;
h32 ^= h32 >> 13;
h32 *= PRIME32_3;
h32 ^= h32 >> 16;
return h32;
}
static inline uint32_t qemu_xxhash2(uint64_t ab)
{
return qemu_xxhash7(ab, 0, 0, 0, 0);
}
static inline uint32_t qemu_xxhash4(uint64_t ab, uint64_t cd)
{
return qemu_xxhash7(ab, cd, 0, 0, 0);
}
static inline uint32_t qemu_xxhash5(uint64_t ab, uint64_t cd, uint32_t e)
{
return qemu_xxhash7(ab, cd, e, 0, 0);
}
static inline uint32_t qemu_xxhash6(uint64_t ab, uint64_t cd, uint32_t e,
uint32_t f)
{
return qemu_xxhash7(ab, cd, e, f, 0);
}
#endif /* QEMU_XXHASH_H */