mirror of
https://github.com/postgres/postgres.git
synced 2026-02-15 00:33:54 -05:00
0052a0243d
This hash function is derived from Boost's function of the same name. Author: Andres Freund, Thomas Munro Discussion: https://postgr.es/m/CAEepm%3D3rdgjfxW4cKvJ0OEmya2-34B0qHNG1xV0vK7TGPJGMUQ%40mail.gmail.com Discussion: https://postgr.es/m/20170731210844.3cwrkmsmbbpt4rjc%40alap3.anarazel.de
23 lines
444 B
C
23 lines
444 B
C
/*
|
|
* Utilities for working with hash values.
|
|
*
|
|
* Portions Copyright (c) 2017, PostgreSQL Global Development Group
|
|
*/
|
|
|
|
#ifndef HASHUTILS_H
|
|
#define HASHUTILS_H
|
|
|
|
/*
|
|
* Combine two hash values, resulting in another hash value, with decent bit
|
|
* mixing.
|
|
*
|
|
* Similar to boost's hash_combine().
|
|
*/
|
|
static inline uint32
|
|
hash_combine(uint32 a, uint32 b)
|
|
{
|
|
a ^= b + 0x9e3779b9 + (a << 6) + (a >> 2);
|
|
return a;
|
|
}
|
|
|
|
#endif /* HASHUTILS_H */
|