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//-----------------------------------------------------------------------------
// MurmurHash3 was written by Austin Appleby, and is placed in the public
// domain. The author hereby disclaims copyright to this source code.
// Note - The x86 and x64 versions do _not_ produce the same results, as the
// algorithms are optimized for their respective platforms. You can still
// compile and run any of them on any platform, but your performance with the
// non-native version will be less than optimal.
#include "MurmurHash3.h"
namespace {
//-----------------------------------------------------------------------------
// Platform-specific functions and macros
// Microsoft Visual Studio
#if defined(_MSC_VER)
# define FORCE_INLINE __forceinline
# define ROTL32(x, y) _rotl(x, y)
# define ROTL64(x, y) _rotl64(x, y)
# define BIG_CONSTANT(x) (x)
// Other compilers
#else // defined(_MSC_VER)
// We can't do always_inline, becasue -Werror -Wattribute will trigger
// a "might not be able to inline" warning.
// #define FORCE_INLINE __attribute__((always_inline))
# define FORCE_INLINE inline
inline uint32_t rotl32(uint32_t x, int8_t r) {
return (x << r) | (x >> (32 - r));
}
inline uint64_t rotl64(uint64_t x, int8_t r) {
return (x << r) | (x >> (64 - r));
}
# define ROTL32(x, y) rotl32(x, y)
# define ROTL64(x, y) rotl64(x, y)
# define BIG_CONSTANT(x) (x##LLU)
#endif // !defined(_MSC_VER)
//-----------------------------------------------------------------------------
// Block read - if your platform needs to do endian-swapping or can only
// handle aligned reads, do the conversion here
FORCE_INLINE uint32_t getblock(const uint32_t* p, int i) { return p[i]; }
FORCE_INLINE uint64_t getblock(const uint64_t* p, int i) { return p[i]; }
//-----------------------------------------------------------------------------
// Finalization mix - force all bits of a hash block to avalanche
FORCE_INLINE uint32_t fmix(uint32_t h) {
h ^= h >> 16;
h *= 0x85ebca6b;
h ^= h >> 13;
h *= 0xc2b2ae35;
h ^= h >> 16;
return h;
}
//----------
FORCE_INLINE uint64_t fmix(uint64_t k) {
k ^= k >> 33;
k *= BIG_CONSTANT(0xff51afd7ed558ccd);
k ^= k >> 33;
k *= BIG_CONSTANT(0xc4ceb9fe1a85ec53);
k ^= k >> 33;
return k;
}
} // unnamed namespace
//-----------------------------------------------------------------------------
void MurmurHash3_x86_32(const void* key, int len, uint32_t seed, void* out) {
const uint8_t* data = (const uint8_t*)key;
const int nblocks = len / 4;
uint32_t h1 = seed;
const uint32_t c1 = 0xcc9e2d51;
const uint32_t c2 = 0x1b873593;
//----------
// body
const uint32_t* blocks = (const uint32_t*)(data + nblocks * 4);
for (int i = -nblocks; i; i++) {
uint32_t k1 = getblock(blocks, i);
k1 *= c1;
k1 = ROTL32(k1, 15);
k1 *= c2;
h1 ^= k1;
h1 = ROTL32(h1, 13);
h1 = h1 * 5 + 0xe6546b64;
}
//----------
// tail
const uint8_t* tail = (const uint8_t*)(data + nblocks * 4);
uint32_t k1 = 0;
switch (len & 3) {
case 3:
k1 ^= tail[2] << 16;
case 2:
k1 ^= tail[1] << 8;
case 1:
k1 ^= tail[0];
k1 *= c1;
k1 = ROTL32(k1, 15);
k1 *= c2;
h1 ^= k1;
}
//----------
// finalization
h1 ^= len;
h1 = fmix(h1);
*(uint32_t*)out = h1;
}
//-----------------------------------------------------------------------------
void MurmurHash3_x86_128(const void* key, const int len, uint32_t seed,
void* out) {
const uint8_t* data = (const uint8_t*)key;
const int nblocks = len / 16;
uint32_t h1 = seed;
uint32_t h2 = seed;
uint32_t h3 = seed;
uint32_t h4 = seed;
const uint32_t c1 = 0x239b961b;
const uint32_t c2 = 0xab0e9789;
const uint32_t c3 = 0x38b34ae5;
const uint32_t c4 = 0xa1e38b93;
//----------
// body
const uint32_t* blocks = (const uint32_t*)(data + nblocks * 16);
for (int i = -nblocks; i; i++) {
uint32_t k1 = getblock(blocks, i * 4 + 0);
uint32_t k2 = getblock(blocks, i * 4 + 1);
uint32_t k3 = getblock(blocks, i * 4 + 2);
uint32_t k4 = getblock(blocks, i * 4 + 3);
k1 *= c1;
k1 = ROTL32(k1, 15);
k1 *= c2;
h1 ^= k1;
h1 = ROTL32(h1, 19);
h1 += h2;
h1 = h1 * 5 + 0x561ccd1b;
k2 *= c2;
k2 = ROTL32(k2, 16);
k2 *= c3;
h2 ^= k2;
h2 = ROTL32(h2, 17);
h2 += h3;
h2 = h2 * 5 + 0x0bcaa747;
k3 *= c3;
k3 = ROTL32(k3, 17);
k3 *= c4;
h3 ^= k3;
h3 = ROTL32(h3, 15);
h3 += h4;
h3 = h3 * 5 + 0x96cd1c35;
k4 *= c4;
k4 = ROTL32(k4, 18);
k4 *= c1;
h4 ^= k4;
h4 = ROTL32(h4, 13);
h4 += h1;
h4 = h4 * 5 + 0x32ac3b17;
}
//----------
// tail
const uint8_t* tail = (const uint8_t*)(data + nblocks * 16);
uint32_t k1 = 0;
uint32_t k2 = 0;
uint32_t k3 = 0;
uint32_t k4 = 0;
switch (len & 15) {
case 15:
k4 ^= tail[14] << 16;
case 14:
k4 ^= tail[13] << 8;
case 13:
k4 ^= tail[12] << 0;
k4 *= c4;
k4 = ROTL32(k4, 18);
k4 *= c1;
h4 ^= k4;
case 12:
k3 ^= tail[11] << 24;
case 11:
k3 ^= tail[10] << 16;
case 10:
k3 ^= tail[9] << 8;
case 9:
k3 ^= tail[8] << 0;
k3 *= c3;
k3 = ROTL32(k3, 17);
k3 *= c4;
h3 ^= k3;
case 8:
k2 ^= tail[7] << 24;
case 7:
k2 ^= tail[6] << 16;
case 6:
k2 ^= tail[5] << 8;
case 5:
k2 ^= tail[4] << 0;
k2 *= c2;
k2 = ROTL32(k2, 16);
k2 *= c3;
h2 ^= k2;
case 4:
k1 ^= tail[3] << 24;
case 3:
k1 ^= tail[2] << 16;
case 2:
k1 ^= tail[1] << 8;
case 1:
k1 ^= tail[0] << 0;
k1 *= c1;
k1 = ROTL32(k1, 15);
k1 *= c2;
h1 ^= k1;
}
//----------
// finalization
h1 ^= len;
h2 ^= len;
h3 ^= len;
h4 ^= len;
h1 += h2;
h1 += h3;
h1 += h4;
h2 += h1;
h3 += h1;
h4 += h1;
h1 = fmix(h1);
h2 = fmix(h2);
h3 = fmix(h3);
h4 = fmix(h4);
h1 += h2;
h1 += h3;
h1 += h4;
h2 += h1;
h3 += h1;
h4 += h1;
((uint32_t*)out)[0] = h1;
((uint32_t*)out)[1] = h2;
((uint32_t*)out)[2] = h3;
((uint32_t*)out)[3] = h4;
}
//-----------------------------------------------------------------------------
void MurmurHash3_x64_128(const void* key, const int len, const uint32_t seed,
void* out) {
const uint8_t* data = (const uint8_t*)key;
const int nblocks = len / 16;
uint64_t h1 = seed;
uint64_t h2 = seed;
const uint64_t c1 = BIG_CONSTANT(0x87c37b91114253d5);
const uint64_t c2 = BIG_CONSTANT(0x4cf5ad432745937f);
//----------
// body
const uint64_t* blocks = (const uint64_t*)(data);
for (int i = 0; i < nblocks; i++) {
uint64_t k1 = getblock(blocks, i * 2 + 0);
uint64_t k2 = getblock(blocks, i * 2 + 1);
k1 *= c1;
k1 = ROTL64(k1, 31);
k1 *= c2;
h1 ^= k1;
h1 = ROTL64(h1, 27);
h1 += h2;
h1 = h1 * 5 + 0x52dce729;
k2 *= c2;
k2 = ROTL64(k2, 33);
k2 *= c1;
h2 ^= k2;
h2 = ROTL64(h2, 31);
h2 += h1;
h2 = h2 * 5 + 0x38495ab5;
}
//----------
// tail
const uint8_t* tail = (const uint8_t*)(data + nblocks * 16);
uint64_t k1 = 0;
uint64_t k2 = 0;
switch (len & 15) {
case 15:
k2 ^= uint64_t(tail[14]) << 48;
case 14:
k2 ^= uint64_t(tail[13]) << 40;
case 13:
k2 ^= uint64_t(tail[12]) << 32;
case 12:
k2 ^= uint64_t(tail[11]) << 24;
case 11:
k2 ^= uint64_t(tail[10]) << 16;
case 10:
k2 ^= uint64_t(tail[9]) << 8;
case 9:
k2 ^= uint64_t(tail[8]) << 0;
k2 *= c2;
k2 = ROTL64(k2, 33);
k2 *= c1;
h2 ^= k2;
case 8:
k1 ^= uint64_t(tail[7]) << 56;
case 7:
k1 ^= uint64_t(tail[6]) << 48;
case 6:
k1 ^= uint64_t(tail[5]) << 40;
case 5:
k1 ^= uint64_t(tail[4]) << 32;
case 4:
k1 ^= uint64_t(tail[3]) << 24;
case 3:
k1 ^= uint64_t(tail[2]) << 16;
case 2:
k1 ^= uint64_t(tail[1]) << 8;
case 1:
k1 ^= uint64_t(tail[0]) << 0;
k1 *= c1;
k1 = ROTL64(k1, 31);
k1 *= c2;
h1 ^= k1;
}
//----------
// finalization
h1 ^= len;
h2 ^= len;
h1 += h2;
h2 += h1;
h1 = fmix(h1);
h2 = fmix(h2);
h1 += h2;
h2 += h1;
((uint64_t*)out)[0] = h1;
((uint64_t*)out)[1] = h2;
}
//-----------------------------------------------------------------------------