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/*
* bitops.h: Bit string operations on the m68k
*/
#ifndef _M68K_BITOPS_H
#define _M68K_BITOPS_H
#include <linux/config.h>
#include <asm/byteorder.h>
extern void set_bit(int nr, volatile void *addr);
extern void clear_bit(int nr, volatile void *addr);
extern void change_bit(int nr, volatile void *addr);
extern int test_and_set_bit(int nr, volatile void *addr);
extern int test_and_clear_bit(int nr, volatile void *addr);
extern int test_and_change_bit(int nr, volatile void *addr);
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#ifdef __KERNEL__
/*
* ffs: find first bit set. This is defined the same way as
* the libc and compiler builtin ffs routines, therefore
* differs in spirit from the above ffz (man ffs).
*/
extern __inline__ int ffs(int x)
{
int r = 1;
if (!x)
return 0;
if (!(x & 0xffff)) {
x >>= 16;
r += 16;
}
if (!(x & 0xff)) {
x >>= 8;
r += 8;
}
if (!(x & 0xf)) {
x >>= 4;
r += 4;
}
if (!(x & 3)) {
x >>= 2;
r += 2;
}
if (!(x & 1)) {
x >>= 1;
r += 1;
}
return r;
}
#define __ffs(x) (ffs(x) - 1)
