mirror of
https://bitbucket.org/librepilot/librepilot.git
synced 2024-12-01 09:24:10 +01:00
54 lines
1.6 KiB
C
54 lines
1.6 KiB
C
/*
|
|
* YAFFS: Yet Another Flash File System. A NAND-flash specific file system.
|
|
*
|
|
* Copyright (C) 2002-2011 Aleph One Ltd.
|
|
* for Toby Churchill Ltd and Brightstar Engineering
|
|
*
|
|
* Created by Charles Manning <charles@aleph1.co.uk>
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License version 2 as
|
|
* published by the Free Software Foundation.
|
|
*/
|
|
|
|
/* These functions have been renamed to hweightxx to match the
|
|
* equivaqlent functions in the Linux kernel.
|
|
*/
|
|
|
|
#include "yaffs_hweight.h"
|
|
|
|
static const char yaffs_count_bits_table[256] = {
|
|
0, 1, 1, 2, 1, 2, 2, 3, 1, 2, 2, 3, 2, 3, 3, 4,
|
|
1, 2, 2, 3, 2, 3, 3, 4, 2, 3, 3, 4, 3, 4, 4, 5,
|
|
1, 2, 2, 3, 2, 3, 3, 4, 2, 3, 3, 4, 3, 4, 4, 5,
|
|
2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5, 4, 5, 5, 6,
|
|
1, 2, 2, 3, 2, 3, 3, 4, 2, 3, 3, 4, 3, 4, 4, 5,
|
|
2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5, 4, 5, 5, 6,
|
|
2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5, 4, 5, 5, 6,
|
|
3, 4, 4, 5, 4, 5, 5, 6, 4, 5, 5, 6, 5, 6, 6, 7,
|
|
1, 2, 2, 3, 2, 3, 3, 4, 2, 3, 3, 4, 3, 4, 4, 5,
|
|
2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5, 4, 5, 5, 6,
|
|
2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5, 4, 5, 5, 6,
|
|
3, 4, 4, 5, 4, 5, 5, 6, 4, 5, 5, 6, 5, 6, 6, 7,
|
|
2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5, 4, 5, 5, 6,
|
|
3, 4, 4, 5, 4, 5, 5, 6, 4, 5, 5, 6, 5, 6, 6, 7,
|
|
3, 4, 4, 5, 4, 5, 5, 6, 4, 5, 5, 6, 5, 6, 6, 7,
|
|
4, 5, 5, 6, 5, 6, 6, 7, 5, 6, 6, 7, 6, 7, 7, 8
|
|
};
|
|
|
|
int yaffs_hweight8(u8 x)
|
|
{
|
|
int ret_val;
|
|
ret_val = yaffs_count_bits_table[x];
|
|
return ret_val;
|
|
}
|
|
|
|
int yaffs_hweight32(u32 x)
|
|
{
|
|
return yaffs_hweight8(x & 0xff) +
|
|
yaffs_hweight8((x >> 8) & 0xff) +
|
|
yaffs_hweight8((x >> 16) & 0xff) +
|
|
yaffs_hweight8((x >> 24) & 0xff);
|
|
}
|
|
|