/*
* Copyright (c) 2016 Positive Technologies, https://www.ptsecurity.com,
* Fast Positive Hash.
*
* Portions Copyright (c) 2010-2016 Leonid Yuriev <leo@yuriev.ru>,
* The 1Hippeus project (t1h).
*
* This software is provided 'as-is', without any express or implied
* warranty. In no event will the authors be held liable for any damages
* arising from the use of this software.
*
* Permission is granted to anyone to use this software for any purpose,
* including commercial applications, and to alter it and redistribute it
* freely, subject to the following restrictions:
*
* 1. The origin of this software must not be misrepresented; you must not
* claim that you wrote the original software. If you use this software
* in a product, an acknowledgement in the product documentation would be
* appreciated but is not required.
* 2. Altered source versions must be plainly marked as such, and must not be
* misrepresented as being the original software.
* 3. This notice may not be removed or altered from any source distribution.
*/
/*
* t1ha = { Fast Positive Hash}
* by [Positive Technologies](https://www.ptsecurity.ru)
*
* Briefly, it is a 64-bit Hash Function:
* 1. Created for 64-bit little-endian platforms, in predominantly for x86_64,
* but without penalties could runs on any 64-bit CPU.
* 2. In most cases up to 15% faster than City64, xxHash, mum-hash, metro-hash
* and all others which are not use specific hardware tricks.
* 3. Not suitable for cryptography.
*
* ACKNOWLEDGEMENT:
* The t1ha was originally developed by Leonid Yuriev
* for The 1Hippeus project - zerocopy messaging in the spirit of Sparta!
*/
#ifndef T1HA_INCLUDED
#define T1HA_INCLUDED
#include "config.h"
#include <string.h>
#include <stddef.h>
#ifndef __has_attribute
#define __has_attribute(x) (0)
#endif
#ifndef __has_builtin
#define __has_builtin(x) (0)
#endif
#ifdef BYTE_ORDER
#ifndef __ORDER_LITTLE_ENDIAN__
#define __ORDER_LITTLE_ENDIAN__ LITTLE_ENDIAN
#endif
#ifndef __ORDER_BIG_ENDIAN__
#define __ORDER_BIG_ENDIAN__ BIG_ENDIAN
#endif
#ifndef __BYTE_ORDER__
#define __BYTE_ORDER__ BYTE_ORDER
#endif
#else
#if !defined(__BYTE_ORDER__) || !defined(__ORDER_LITTLE_ENDIAN__) || \
!defined(__ORDER_BIG_ENDIAN__)
#define __ORDER_LITTLE_ENDIAN__ 1234
#define __ORDER_BIG_ENDIAN__ 4321
#if defined(__LITTLE_ENDIAN__) || defined(__ARMEL__) || \
defined(__THUMBEL__) || defined(__AARCH64EL__) || defined(__MIPSEL__) || \
defined(_MIPSEL) || defined(__MIPSEL) || defined(__i386) || \
defined(__x86_64) || defined(_M_IX86) || defined(_M_X64) || \
defined(i386) || defined(_X86_) || defined(__i386__) || defined(_X86_64_)
#define __BYTE_ORDER__ __ORDER_LITTLE_ENDIAN__
#elif defined(__BIG_ENDIAN__) || defined(__ARMEB__) || defined(__THUMBEB__) || \
defined(__AARCH64EB__) || defined(__MIPSEB__) || defined(_MIPSEB) || \
defined(__MIPSEB)
#define __BYTE_ORDER__ __ORDER_BIG_ENDIAN__
#else
#error __BYTE_ORDER__ should be defined.
#endif
#endif
#endif
#if __BYTE_ORDER__ != __ORDER_LITTLE_ENDIAN__ && \
__BYTE_ORDER__ != __ORDER_BIG_ENDIAN__
#error Unsupported byte order.
#endif
#if !defined(UNALIGNED_OK)
#if defined(__i386) || defined(__x86_64) || defined(_M_IX86) || \
defined(_M_X64) || defined(i386) || defined(_X86_) || defined(__i386__) || \
defined(_X86_64_)
#define UNALIGNED_OK 1
#else
#define UNALIGNED_OK 0
#endif
#endif
#ifndef __GNUC_PREREQ
#if defined(__GNUC__) && defined(__GNUC_MINOR__)
#define __GNUC_PREREQ(maj, min) \
((__GNUC__ << 16) + __GNUC_MINOR__ >= ((maj) << 16) + (min))
#else
#define __GNUC_PREREQ(maj, min) 0
#endif
#endif
#if __GNUC_PREREQ(4, 4) || defined(__clang__)
#if defined(__i386__) || defined(__x86_64__)
#include <x86intrin.h>
#endif
#define likely(cond) __builtin_expect(!!(cond), 1)
#define unlikely(cond) __builtin_expect(!!(cond), 0)
# if __GNUC_PREREQ(4, 6) || defined(__clang__)
#define unreachable() __builtin_unreachable()
# else
#define unreachable() \
do { \
for (;;) \
; \
} while (0)
# endif
#define bswap64(v) __builtin_bswap64(v)
#define bswap32(v) __builtin_bswap32(v)
#if __GNUC_PREREQ(4, 8) || __has_builtin(__builtin_bswap16)
#define bswap16(v) __builtin_bswap16(v)
#endif
#if __GNUC_PREREQ(4, 3) || __has_attribute(unused)
#define maybe_unused __attribute__((unused))
#endif
#elif defined(_MSC_VER)
#include <intrin.h>
#include <stdlib.h>
#define likely(cond) (cond)
#define unlikely(cond) (cond)
#define unreachable() __assume(0)
#define bswap64(v) _byteswap_uint64(v)
#define bswap32(v) _byteswap_ulong(v)
#define bswap16(v) _byteswap_ushort(v)
#define rot64(v, s) _rotr64(v, s)
#define rot32(v, s) _rotr(v, s)
#if defined(_M_ARM64) || defined(_M_X64)
#pragma intrinsic(_umul128)
#define mul_64x64_128(a, b, ph) _umul128(a, b, ph)
#pragma intrinsic(__umulh)
#define mul_64x64_high(a, b) __umulh(a, b)
#endif
#if defined(_M_IX86)
#pragma intrinsic(__emulu)
#define mul_32x32_64(a, b) __emulu(a, b)
#elif defined(_M_ARM)
#define mul_32x32_64(a, b) _arm_umull(a, b)
#endif
#else /* Compiler */
#define likely(cond) (cond)
#define unlikely(cond) (cond)
#define unreachable() \
do \
for (;;) \
; \
while (0)
#endif /* Compiler */
#ifndef bswap64
static __inline uint64_t bswap64(uint64_t v) {
return v << 56 | v >> 56 | ((v << 40) & 0x00ff000000000000ull) |
((v << 24) & 0x0000ff0000000000ull) |
((v << 8) & 0x000000ff00000000ull) |
((v >> 8) & 0x00000000ff000000ull) |
((v >> 24) & 0x0000000000ff0000ull) |
((v >> 40) & 0x000000000000ff00ull);
}
#endif /* bswap64 */
#ifndef bswap32
static __inline uint32_t bswap32(uint32_t v) {
return v << 24 | v >> 24 | ((v << 8) & 0x00ff0000) | ((v >> 8) & 0x0000ff00);
}
#endif /* bswap32 */
#ifndef bswap16
static __inline uint16_t bswap16(uint16_t v) { return v << 8 | v >> 8; }
#endif /* bswap16 */
#ifndef rot64
static __inline uint64_t rot64(uint64_t v, unsigned s) {
return (v >> s) | (v << (64 - s));
}
#endif /* rot64 */
#ifndef rot32
static __inline uint32_t rot32(uint32_t v, unsigned s) {
return (v >> s) | (v << (32 - s));
}
#endif /* rot32 */
#ifndef mul_32x32_64
static __inline uint64_t mul_32x32_64(uint32_t a, uint32_t b) {
return a * (uint64_t)b;
}
#endif /* mul_32x32_64 */
/***************************************************************************/
static __inline uint64_t fetch64(const void *v) {
#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
return *(const uint64_t *)v;
#else
return bswap64(*(const uint64_t *)v);
#endif
}
static __inline uint64_t fetch32(const void *v) {
#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
return *(const uint32_t *)v;
#else
return bswap32(*(const uint32_t *)v);
#endif
}
static __inline uint64_t fetch16(const void *v) {
#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
return *(const uint16_t *)v;
#else
return bswap16(*(const uint16_t *)v);
#endif
}
static __inline uint64_t fetch_tail(const void *v, size_t tail) {
const uint8_t *_ = (const uint8_t *)v;
switch (tail & 7) {
case 1:
return _[0];
case 2:
return fetch16(_);
case 3:
return fetch16(_) | (_[2] << 16);
case 4:
return fetch32(_);
case 5:
return fetch32(_) | ((uint64_t)_[4] << 32);
case 6:
return fetch32(_) | (fetch16(_ + 4) << 32);
case 7:
return fetch32(_) | (fetch16(_ + 4) << 32) | ((uint64_t)_[6] << 48);
case 0:
return fetch64(_);
default:
unreachable();
}
}
/* xor-mul-xor mixer */
static __inline uint64_t mix(uint64_t v, uint64_t p) {
static const unsigned s0 = 41;
v *= p;
return v ^ rot64(v, s0);
}
static __inline unsigned add_with_carry(uint64_t *sum, uint64_t addend) {
*sum += addend;
return *sum < addend;
}
/* xor high and low parts of full 128-bit product */
static __inline uint64_t mux64(uint64_t v, uint64_t p) {
#ifdef __SIZEOF_INT128__
__uint128_t r = (__uint128_t)v * (__uint128_t)p;
/* modern GCC could nicely optimize this */
return r ^ (r >> 64);
#elif defined(_INTEGRAL_MAX_BITS) && _INTEGRAL_MAX_BITS >= 128
__uint128 r = (__uint128)v * (__uint128)p;
return r ^ (r >> 64);
#elif defined(mul_64x64_128)
uint64_t l, h;
l = mul_64x64_128(v, p, &h);
return l ^ h;
#elif defined(mul_64x64_high)
uint64_t l, h;
l = v * p;
h = mul_64x64_high(v, p);
return l ^ h;
#else
/* performs 64x64 to 128 bit multiplication */
uint64_t ll = mul_32x32_64((uint32_t)v, (uint32_t)p);
uint64_t lh = mul_32x32_64(v >> 32, (uint32_t)p);
uint64_t hl = mul_32x32_64(p >> 32, (uint32_t)v);
uint64_t hh =
mul_32x32_64(v >> 32, p >> 32) + (lh >> 32) + (hl >> 32) +
/* Few simplification are possible here for 32-bit architectures,
* but thus we would lost compatibility with the original 64-bit
* version. Think is very bad idea, because then 32-bit t1ha will
* still (relatively) very slowly and well yet not compatible. */
add_with_carry(&ll, lh << 32) + add_with_carry(&ll, hl << 32);
return hh ^ ll;
#endif
}
static uint64_t
t1ha(const void *data, size_t len, uint64_t seed)
{
/* 'magic' primes */
static const uint64_t p0 = 17048867929148541611ull;
static const uint64_t p1 = 9386433910765580089ull;
static const uint64_t p2 = 15343884574428479051ull;
static const uint64_t p3 = 13662985319504319857ull;
static const uint64_t p4 = 11242949449147999147ull;
static const uint64_t p5 = 13862205317416547141ull;
static const uint64_t p6 = 14653293970879851569ull;
/* rotations */
static const unsigned s0 = 41;
static const unsigned s1 = 17;
static const unsigned s2 = 31;
uint64_t a = seed;
uint64_t b = len;
const int need_align = (((uintptr_t)data) & 7) != 0 && !UNALIGNED_OK;
uint64_t align[4];
if (unlikely(len > 32)) {
uint64_t c = rot64(len, s1) + seed;
uint64_t d = len ^ rot64(seed, s1);
const void *detent = (const uint8_t *)data + len - 31;
do {
const uint64_t *v = (const uint64_t *)data;
if (unlikely(need_align))
v = (const uint64_t *)memcpy(&align, v, 32);
uint64_t w0 = fetch64(v + 0);
uint64_t w1 = fetch64(v + 1);
uint64_t w2 = fetch64(v + 2);
uint64_t w3 = fetch64(v + 3);
uint64_t d02 = w0 ^ rot64(w2 + d, s1);
uint64_t c13 = w1 ^ rot64(w3 + c, s1);
c += a ^ rot64(w0, s0);
d -= b ^ rot64(w1, s2);
a ^= p1 * (d02 + w3);
b ^= p0 * (c13 + w2);
data = (const uint64_t *)data + 4;
} while (likely(data < detent));
a ^= p6 * (rot64(c, s1) + d);
b ^= p5 * (c + rot64(d, s1));
len &= 31;
}
const uint64_t *v = (const uint64_t *)data;
if (unlikely(need_align) && len > 1)
v = (const uint64_t *)memcpy(&align, v, len);
switch (len) {
default:
b += mux64(fetch64(v++), p4);
case 24:
case 23:
case 22:
case 21:
case 20:
case 19:
case 18:
case 17:
a += mux64(fetch64(v++), p3);
case 16:
case 15:
case 14:
case 13:
case 12:
case 11:
case 10:
case 9:
b += mux64(fetch64(v++), p2);
case 8:
case 7:
case 6:
case 5:
case 4:
case 3:
case 2:
case 1:
a += mux64(fetch_tail(v, len), p1);
case 0:
return mux64(rot64(a + b, s1), p4) + mix(a ^ b, p0);
}
}
static __inline uint32_t tail32_le(const void *v, size_t tail) {
const uint8_t *p = (const uint8_t *)v;
uint32_t r = 0;
switch (tail & 3) {
#if UNALIGNED_OK && __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
/* For most CPUs this code is better when not needed
* copying for alignment or byte reordering. */
case 0:
return fetch32(p);
case 3:
r = (uint32_t)p[2] << 16;
case 2:
return r + fetch16(p);
case 1:
return p[0];
#else
/* For most CPUs this code is better than a
* copying for alignment and/or byte reordering. */
case 0:
r += p[3];
r <<= 8;
case 3:
r += p[2];
r <<= 8;
case 2:
r += p[1];
r <<= 8;
case 1:
return r + p[0];
#endif
}
unreachable();
}
static __inline uint32_t tail32_be(const void *v, size_t tail) {
const uint8_t *p = (const uint8_t *)v;
switch (tail & 3) {
#if UNALIGNED_OK && __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
/* For most CPUs this code is better when not needed
* copying for alignment or byte reordering. */
case 1:
return p[0];
case 2:
return fetch16_be(p);
case 3:
return fetch16_be(p) << 8 | p[2];
case 0:
return fetch32_be(p);
#else
/* For most CPUs this code is better than a
* copying for alignment and/or byte reordering. */
case 1:
return p[0];
case 2:
return p[1] | (uint32_t)p[0] << 8;
case 3:
return p[2] | (uint32_t)p[1] << 8 | (uint32_t)p[0] << 16;
case 0:
return p[3] | (uint32_t)p[2] << 8 | (uint32_t)p[1] << 16 |
(uint32_t)p[0] << 24;
#endif
}
unreachable();
}
static __inline uint64_t remix32(uint32_t a, uint32_t b) {
static const uint64_t p0 = 17048867929148541611ull;
a ^= rot32(b, 13);
uint64_t l = a | (uint64_t)b << 32;
l *= p0;
l ^= l >> 41;
return l;
}
static __inline void mixup32(uint32_t *a, uint32_t *b, uint32_t v, uint32_t p) {
uint64_t l = mul_32x32_64(*b + v, p);
*a ^= (uint32_t)l;
*b += (uint32_t)(l >> 32);
}
static uint64_t t1ha32(const void *data, size_t len, uint64_t seed) {
/* 32-bit 'magic' primes */
static const uint32_t q0 = 0x92D78269;
static const uint32_t q1 = 0xCA9B4735;
static const uint32_t q2 = 0xA4ABA1C3;
static const uint32_t q3 = 0xF6499843;
static const uint32_t q4 = 0x86F0FD61;
static const uint32_t q5 = 0xCA2DA6FB;
static const uint32_t q6 = 0xC4BB3575;
/* rotations */
static const unsigned s1 = 17;
uint32_t a = rot32((uint32_t)len, s1) + (uint32_t)seed;
uint32_t b = (uint32_t)len ^ (uint32_t)(seed >> 32);
const int need_align = (((uintptr_t)data) & 3) != 0 && !UNALIGNED_OK;
uint32_t align[4];
if (unlikely(len > 16)) {
uint32_t c = ~a;
uint32_t d = rot32(b, 5);
const void *detent = (const uint8_t *)data + len - 15;
do {
const uint32_t *v = (const uint32_t *)data;
if (unlikely(need_align))
v = (const uint32_t *)memcpy(&align, v, 16);
uint32_t w0 = fetch32(v + 0);
uint32_t w1 = fetch32(v + 1);
uint32_t w2 = fetch32(v + 2);
uint32_t w3 = fetch32(v + 3);
uint32_t c02 = w0 ^ rot32(w2 + c, 11);
uint32_t d13 = w1 + rot32(w3 + d, s1);
c ^= rot32(b + w1, 7);
d ^= rot32(a + w0, 3);
b = q1 * (c02 + w3);
a = q0 * (d13 ^ w2);
data = (const uint32_t *)data + 4;
} while (likely(data < detent));
c += a;
d += b;
a ^= q6 * (rot32(c, 16) + d);
b ^= q5 * (c + rot32(d, 16));
len &= 15;
}
const uint8_t *v = (const uint8_t *)data;
if (unlikely(need_align) && len > 4)
v = (const uint8_t *)memcpy(&align, v, len);
switch (len) {
default:
mixup32(&a, &b, fetch32(v), q4);
v += 4;
case 12:
case 11:
case 10:
case 9:
mixup32(&b, &a, fetch32(v), q3);
v += 4;
case 8:
case 7:
case 6:
case 5:
mixup32(&a, &b, fetch32(v), q2);
v += 4;
case 4:
case 3:
case 2:
case 1:
mixup32(&b, &a, tail32_le(v, len), q1);
case 0:
return remix32(a, b);
}
}
#endif