/*
* 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);
}
/*
* Component parts of the XXH64 algorithm from
* https://github.com/Cyan4973/xxHash/blob/v0.8.0/xxhash.h
*
* The complete algorithm looks like
*
* i = 0;
* if (len >= 32) {
* v1 = seed + XXH_PRIME64_1 + XXH_PRIME64_2;
* v2 = seed + XXH_PRIME64_2;
* v3 = seed + 0;
* v4 = seed - XXH_PRIME64_1;
* do {
* v1 = XXH64_round(v1, get64bits(input + i));
* v2 = XXH64_round(v2, get64bits(input + i + 8));
* v3 = XXH64_round(v3, get64bits(input + i + 16));
* v4 = XXH64_round(v4, get64bits(input + i + 24));
* } while ((i += 32) <= len);
* h64 = XXH64_mergerounds(v1, v2, v3, v4);
* } else {
* h64 = seed + XXH_PRIME64_5;
* }
* h64 += len;
*
* for (; i + 8 <= len; i += 8) {
* h64 ^= XXH64_round(0, get64bits(input + i));
* h64 = rol64(h64, 27) * XXH_PRIME64_1 + XXH_PRIME64_4;
* }
* for (; i + 4 <= len; i += 4) {
* h64 ^= get32bits(input + i) * PRIME64_1;
* h64 = rol64(h64, 23) * XXH_PRIME64_2 + XXH_PRIME64_3;
* }
* for (; i < len; i += 1) {
* h64 ^= get8bits(input + i) * XXH_PRIME64_5;
* h64 = rol64(h64, 11) * XXH_PRIME64_1;
* }
*
* return XXH64_avalanche(h64)
*
* Exposing the pieces instead allows for simplified usage when
* the length is a known constant and the inputs are in registers.
*/
#define XXH_PRIME64_1 0x9E3779B185EBCA87ULL
#define XXH_PRIME64_2 0xC2B2AE3D27D4EB4FULL
#define XXH_PRIME64_3 0x165667B19E3779F9ULL
#define XXH_PRIME64_4 0x85EBCA77C2B2AE63ULL
#define XXH_PRIME64_5 0x27D4EB2F165667C5ULL
static inline uint64_t XXH64_round(uint64_t acc, uint64_t input)
{
return rol64(acc + input * XXH_PRIME64_2, 31) * XXH_PRIME64_1;
}
static inline uint64_t XXH64_mergeround(uint64_t acc, uint64_t val)
{
return (acc ^ XXH64_round(0, val)) * XXH_PRIME64_1 + XXH_PRIME64_4;
}
static inline uint64_t XXH64_mergerounds(uint64_t v1, uint64_t v2,
uint64_t v3, uint64_t v4)
{
uint64_t h64;
h64 = rol64(v1, 1) + rol64(v2, 7) + rol64(v3, 12) + rol64(v4, 18);
h64 = XXH64_mergeround(h64, v1);
h64 = XXH64_mergeround(h64, v2);
h64 = XXH64_mergeround(h64, v3);
h64 = XXH64_mergeround(h64, v4);
return h64;
}
static inline uint64_t XXH64_avalanche(uint64_t h64)
{
h64 ^= h64 >> 33;
h64 *= XXH_PRIME64_2;
h64 ^= h64 >> 29;
h64 *= XXH_PRIME64_3;
h64 ^= h64 >> 32;
return h64;
}
static inline uint64_t qemu_xxhash64_4(uint64_t a, uint64_t b,
uint64_t c, uint64_t d)
{
uint64_t v1 = QEMU_XXHASH_SEED + XXH_PRIME64_1 + XXH_PRIME64_2;
uint64_t v2 = QEMU_XXHASH_SEED + XXH_PRIME64_2;
uint64_t v3 = QEMU_XXHASH_SEED + 0;
uint64_t v4 = QEMU_XXHASH_SEED - XXH_PRIME64_1;
v1 = XXH64_round(v1, a);
v2 = XXH64_round(v2, b);
v3 = XXH64_round(v3, c);
v4 = XXH64_round(v4, d);
return XXH64_avalanche(XXH64_mergerounds(v1, v2, v3, v4));
}
#endif /* QEMU_XXHASH_H */
