| // 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. |
| |
| // Originally taken from: https://code.google.com/p/smhasher/source/browse/trunk/MurmurHash3.cpp |
| |
| #include "hash.h" |
| |
| //----------------------------------------------------------------------------- |
| // Platform-specific functions and macros |
| |
| // Microsoft Visual Studio |
| |
| #if defined(_MSC_VER) |
| |
| #define FORCE_INLINE __forceinline |
| |
| #include <stdlib.h> |
| |
| #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) |
| |
| #define FORCE_INLINE inline __attribute__((always_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 getblock32_aligned(const uint32_t* p, int i) { |
| return p[i]; |
| } |
| |
| FORCE_INLINE uint32_t getblock32_unaligned(const uint32_t* p, int i) { |
| auto b = reinterpret_cast<const uint8_t*>(p); |
| return (static_cast<uint32_t>(b[0]) << 24) |
| | (static_cast<uint32_t>(b[1]) << 16) |
| | (static_cast<uint32_t>(b[2]) << 8) |
| | static_cast<uint32_t>(b[3]); |
| } |
| |
| FORCE_INLINE uint64_t getblock64_aligned(const uint64_t * p, int i) { |
| return p[i]; |
| } |
| |
| FORCE_INLINE uint64_t getblock64_unaligned(const uint64_t * p, int i) { |
| auto b = reinterpret_cast<const uint8_t*>(p); |
| return (static_cast<uint64_t>(b[0]) << 56) |
| | (static_cast<uint64_t>(b[1]) << 48) |
| | (static_cast<uint64_t>(b[2]) << 40) |
| | (static_cast<uint64_t>(b[3]) << 32) |
| | (static_cast<uint64_t>(b[4]) << 24) |
| | (static_cast<uint64_t>(b[5]) << 16) |
| | (static_cast<uint64_t>(b[6]) << 8) |
| | static_cast<uint64_t>(b[7]); |
| } |
| |
| //----------------------------------------------------------------------------- |
| // Finalization mix - force all bits of a hash block to avalanche |
| |
| FORCE_INLINE uint32_t fmix32(uint32_t h) |
| { |
| h ^= h >> 16; |
| h *= 0x85ebca6b; |
| h ^= h >> 13; |
| h *= 0xc2b2ae35; |
| h ^= h >> 16; |
| |
| return h; |
| } |
| |
| //---------- |
| |
| FORCE_INLINE uint64_t fmix64(uint64_t k) |
| { |
| k ^= k >> 33; |
| k *= BIG_CONSTANT(0xff51afd7ed558ccd); |
| k ^= k >> 33; |
| k *= BIG_CONSTANT(0xc4ceb9fe1a85ec53); |
| k ^= k >> 33; |
| |
| return k; |
| } |
| |
| //----------------------------------------------------------------------------- |
| |
| template<uint32_t (*getblock)(const uint32_t * p, int i)> |
| 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 = fmix32(h1); |
| |
| *(uint32_t*)out = h1; |
| } |
| |
| //----------------------------------------------------------------------------- |
| |
| template<uint32_t (*getblock)(const uint32_t * p, int i)> |
| 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 = fmix32(h1); |
| h2 = fmix32(h2); |
| h3 = fmix32(h3); |
| h4 = fmix32(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; |
| } |
| |
| //----------------------------------------------------------------------------- |
| |
| template<uint64_t (*getblock)(const uint64_t * p, int i)> |
| 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 = fmix64(h1); |
| h2 = fmix64(h2); |
| |
| h1 += h2; |
| h2 += h1; |
| |
| ((uint64_t*)out)[0] = h1; |
| ((uint64_t*)out)[1] = h2; |
| } |
| |
| void MurmurHash3_x86_32(const void * key, int len, uint32_t seed, void * out) { |
| if ((reinterpret_cast<uint64_t>(key) & 0x3) == 0) { |
| MurmurHash3_x86_32_<getblock32_aligned>(key, len, seed, out); |
| } else { |
| MurmurHash3_x86_32_<getblock32_unaligned>(key, len, seed, out); |
| } |
| } |
| |
| void MurmurHash3_x86_128(const void * key, const int len, uint32_t seed, void * out) { |
| if ((reinterpret_cast<uint64_t>(key) & 0x3) == 0) { |
| MurmurHash3_x86_128_<getblock32_aligned>(key, len, seed, out); |
| } else { |
| MurmurHash3_x86_128_<getblock32_unaligned>(key, len, seed, out); |
| } |
| } |
| |
| void MurmurHash3_x64_128(const void * key, const int len, uint32_t seed, void * out) { |
| if ((reinterpret_cast<uint64_t>(key) & 0x7) == 0) { |
| MurmurHash3_x64_128_<getblock64_aligned>(key, len, seed, out); |
| } else { |
| MurmurHash3_x64_128_<getblock64_unaligned>(key, len, seed, out); |
| } |
| } |
| |