//----------------------------------------------------------------------------- // 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" #include <stdlib.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; } //-----------------------------------------------------------------------------