linux-sg2042/arch/unicore32/include/asm/bitops.h

48 lines
1.2 KiB
C

/*
* linux/arch/unicore32/include/asm/bitops.h
*
* Code specific to PKUnity SoC and UniCore ISA
*
* Copyright (C) 2001-2010 GUAN Xue-tao
*
* 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.
*/
#ifndef __UNICORE_BITOPS_H__
#define __UNICORE_BITOPS_H__
#define _ASM_GENERIC_BITOPS_FLS_H_
#define _ASM_GENERIC_BITOPS___FLS_H_
#define _ASM_GENERIC_BITOPS_FFS_H_
#define _ASM_GENERIC_BITOPS___FFS_H_
/*
* On UNICORE, those functions can be implemented around
* the cntlz instruction for much better code efficiency.
*/
static inline int fls(int x)
{
int ret;
asm("cntlz\t%0, %1" : "=r" (ret) : "r" (x) : "cc");
ret = 32 - ret;
return ret;
}
#define __fls(x) (fls(x) - 1)
#define ffs(x) ({ unsigned long __t = (x); fls(__t & -__t); })
#define __ffs(x) (ffs(x) - 1)
#include <asm-generic/bitops.h>
/* following definitions: to avoid using codes in lib/find_*.c */
#define find_next_bit find_next_bit
#define find_next_zero_bit find_next_zero_bit
#define find_first_bit find_first_bit
#define find_first_zero_bit find_first_zero_bit
#endif /* __UNICORE_BITOPS_H__ */