coreboot-libre-fam15h-rdimm/3rdparty/ffs/clib/hash.h

62 lines
2.6 KiB
C

/* IBM_PROLOG_BEGIN_TAG */
/* This is an automatically generated prolog. */
/* */
/* $Source: clib/hash.h $ */
/* */
/* OpenPOWER FFS Project */
/* */
/* Contributors Listed Below - COPYRIGHT 2014,2015 */
/* [+] International Business Machines Corp. */
/* */
/* */
/* Licensed under the Apache License, Version 2.0 (the "License"); */
/* you may not use this file except in compliance with the License. */
/* You may obtain a copy of the License at */
/* */
/* http://www.apache.org/licenses/LICENSE-2.0 */
/* */
/* Unless required by applicable law or agreed to in writing, software */
/* distributed under the License is distributed on an "AS IS" BASIS, */
/* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or */
/* implied. See the License for the specific language governing */
/* permissions and limitations under the License. */
/* */
/* IBM_PROLOG_END_TAG */
/*
* File: hash.h
* Author: Shaun Wetzstein <shaun@us.ibm.com>
* Descr: Various int64 hash functions
* Note:
* Date: 10/03/10
*/
#ifndef __HASH_H__
#define __HASH_H__
#include <stdint.h>
/* ======================================================================= */
static inline int64_t int64_hash1(int64_t);
typedef uint64_t(*hash_t) (char *, uint64_t);
/* ======================================================================= */
static inline int64_t int64_hash1(int64_t key)
{
key = ~key + (key << 15);
key = key ^ (key >> 12);
key = key + (key << 2);
key = key ^ (key >> 4);
key = key * 2057;
key = key ^ (key >> 16);
return key;
}
/* ======================================================================= */
#endif /* __HASH_H__ */