ref: 4cd78cb562334a8106b94d690b31b53f43f81018
dir: /llt/ptrhash.c/
/* pointer hash table optimized for storing info about particular values */ #include <stdlib.h> #include <stdio.h> #include <string.h> #include <assert.h> #include <limits.h> #include "dtypes.h" #include "ptrhash.h" #define OP_EQ(x,y) ((x)==(y)) #ifdef BITS64 static u_int64_t _pinthash(u_int64_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; } #else static u_int32_t _pinthash(u_int32_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; } #endif #include "htable.inc" HTIMPL(ptrhash, _pinthash, OP_EQ)