From 80686d4e567bae579ea39e009826a2de92cd4ace Mon Sep 17 00:00:00 2001 From: redpony Date: Wed, 11 Aug 2010 02:37:10 +0000 Subject: major refactor, break bad circular deps git-svn-id: https://ws10smt.googlecode.com/svn/trunk@509 ec762483-ff6d-05da-a07a-a48fb63a330f --- decoder/murmur_hash.h | 186 -------------------------------------------------- 1 file changed, 186 deletions(-) delete mode 100755 decoder/murmur_hash.h (limited to 'decoder/murmur_hash.h') diff --git a/decoder/murmur_hash.h b/decoder/murmur_hash.h deleted file mode 100755 index 8dbd7807..00000000 --- a/decoder/murmur_hash.h +++ /dev/null @@ -1,186 +0,0 @@ -#ifndef _MURMUR_HASH_H_ -#define _MURMUR_HASH_H_ - -//NOTE: quite fast, nice collision properties, but endian dependent hash values - -#include "have_64_bits.h" -typedef uintptr_t MurmurInt; - -// MurmurHash2, by Austin Appleby - -static const uint32_t DEFAULT_SEED=2654435769U; - -#if HAVE_64_BITS -//MurmurInt MurmurHash(void const *key, int len, uint32_t seed=DEFAULT_SEED); - -inline uint64_t MurmurHash64( const void * key, int len, unsigned int seed=DEFAULT_SEED ) -{ - const uint64_t m = 0xc6a4a7935bd1e995; - const int r = 47; - - uint64_t h = seed ^ (len * m); - - const uint64_t * data = (const uint64_t *)key; - const uint64_t * end = data + (len/8); - - while(data != end) - { - uint64_t k = *data++; - - k *= m; - k ^= k >> r; - k *= m; - - h ^= k; - h *= m; - } - - const unsigned char * data2 = (const unsigned char*)data; - - switch(len & 7) - { - case 7: h ^= uint64_t(data2[6]) << 48; - case 6: h ^= uint64_t(data2[5]) << 40; - case 5: h ^= uint64_t(data2[4]) << 32; - case 4: h ^= uint64_t(data2[3]) << 24; - case 3: h ^= uint64_t(data2[2]) << 16; - case 2: h ^= uint64_t(data2[1]) << 8; - case 1: h ^= uint64_t(data2[0]); - h *= m; - }; - - h ^= h >> r; - h *= m; - h ^= h >> r; - - return h; -} - -inline uint32_t MurmurHash32(void const *key, int len, uint32_t seed=DEFAULT_SEED) -{ - return (uint32_t) MurmurHash64(key,len,seed); -} - -inline MurmurInt MurmurHash(void const *key, int len, uint32_t seed=DEFAULT_SEED) -{ - return MurmurHash64(key,len,seed); -} - -#else -// 32-bit - -// Note - This code makes a few assumptions about how your machine behaves - -// 1. We can read a 4-byte value from any address without crashing -// 2. sizeof(int) == 4 -inline uint32_t MurmurHash32 ( const void * key, int len, uint32_t seed=DEFAULT_SEED) -{ - // 'm' and 'r' are mixing constants generated offline. - // They're not really 'magic', they just happen to work well. - - const uint32_t m = 0x5bd1e995; - const int r = 24; - - // Initialize the hash to a 'random' value - - uint32_t h = seed ^ len; - - // Mix 4 bytes at a time into the hash - - const unsigned char * data = (const unsigned char *)key; - - while(len >= 4) - { - uint32_t k = *(uint32_t *)data; - - k *= m; - k ^= k >> r; - k *= m; - - h *= m; - h ^= k; - - data += 4; - len -= 4; - } - - // Handle the last few bytes of the input array - - switch(len) - { - case 3: h ^= data[2] << 16; - case 2: h ^= data[1] << 8; - case 1: h ^= data[0]; - h *= m; - }; - - // Do a few final mixes of the hash to ensure the last few - // bytes are well-incorporated. - - h ^= h >> 13; - h *= m; - h ^= h >> 15; - - return h; -} - -inline MurmurInt MurmurHash ( const void * key, int len, uint32_t seed=DEFAULT_SEED) { - return MurmurHash32(key,len,seed); -} - -// 64-bit hash for 32-bit platforms - -inline uint64_t MurmurHash64 ( const void * key, int len, uint32_t seed=DEFAULT_SEED) -{ - const uint32_t m = 0x5bd1e995; - const int r = 24; - - uint32_t h1 = seed ^ len; - uint32_t h2 = 0; - - const uint32_t * data = (const uint32_t *)key; - - while(len >= 8) - { - uint32_t k1 = *data++; - k1 *= m; k1 ^= k1 >> r; k1 *= m; - h1 *= m; h1 ^= k1; - len -= 4; - - uint32_t k2 = *data++; - k2 *= m; k2 ^= k2 >> r; k2 *= m; - h2 *= m; h2 ^= k2; - len -= 4; - } - - if(len >= 4) - { - uint32_t k1 = *data++; - k1 *= m; k1 ^= k1 >> r; k1 *= m; - h1 *= m; h1 ^= k1; - len -= 4; - } - - switch(len) - { - case 3: h2 ^= ((unsigned char*)data)[2] << 16; - case 2: h2 ^= ((unsigned char*)data)[1] << 8; - case 1: h2 ^= ((unsigned char*)data)[0]; - h2 *= m; - }; - - h1 ^= h2 >> 18; h1 *= m; - h2 ^= h1 >> 22; h2 *= m; - h1 ^= h2 >> 17; h1 *= m; - h2 ^= h1 >> 19; h2 *= m; - - uint64_t h = h1; - - h = (h << 32) | h2; - - return h; -} - -#endif -//32bit - -#endif -- cgit v1.2.3