ref: 1b0eb3b4437a74231451a95225233fada1039876
dir: /llt/hashing.c/
#include "llt.h" lltuint_t nextipow2(lltuint_t i) { if (i==0) return 1; i |= i >> 1; i |= i >> 2; i |= i >> 4; i |= i >> 8; i |= i >> 16; #ifdef BITS64 i |= i >> 32; #endif i++; return i ? i : TOP_BIT; } uint32_t int32hash(uint32_t a) { a = (a+0x7ed55d16) + (a<<12); a = (a^0xc761c23c) ^ (a>>19); a = (a+0x165667b1) + (a<<5); a = (a+0xd3a2646c) ^ (a<<9); a = (a+0xfd7046c5) + (a<<3); a = (a^0xb55a4f09) ^ (a>>16); return a; } uint64_t int64hash(uint64_t key) { key = (~key) + (key << 21); // key = (key << 21) - key - 1; key = key ^ (key >> 24); key = (key + (key << 3)) + (key << 8); // key * 265 key = key ^ (key >> 14); key = (key + (key << 2)) + (key << 4); // key * 21 key = key ^ (key >> 28); key = key + (key << 31); return key; } uint32_t int64to32hash(uint64_t key) { key = (~key) + (key << 18); // key = (key << 18) - key - 1; key = key ^ (key >> 31); key = key * 21; // key = (key + (key << 2)) + (key << 4); key = key ^ (key >> 11); key = key + (key << 6); key = key ^ (key >> 22); return (uint32_t)key; } #include "lookup3.c" uint64_t memhash(const char* buf, size_t n) { uint32_t c=0xcafe8881, b=0x4d6a087c; hashlittle2(buf, n, &c, &b); return (uint64_t)c | (((uint64_t)b)<<32); } uint32_t memhash32(const char* buf, size_t n) { uint32_t c=0xcafe8881, b=0x4d6a087c; hashlittle2(buf, n, &c, &b); return c; }