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/*
* Copyright (C) 2002 Manuel Novoa III
* Copyright (C) 2000-2005 Erik Andersen <andersen@uclibc.org>
*
* Licensed under the LGPL v2.1, see the file COPYING.LIB in this tarball.
*/
/* ffsl,ffsll */
#include "_string.h"
int ffs(int i)
{
#if 1
/* inlined binary search method */
char n = 1;
#if UINT_MAX == 0xffffU
/* nothing to do here -- just trying to avoiding possible problems */
#elif UINT_MAX == 0xffffffffU
if (!(i & 0xffff)) {
n += 16;
i >>= 16;
}
#else
#error ffs needs rewriting!
#endif
if (!(i & 0xff)) {
n += 8;
i >>= 8;
}
if (!(i & 0x0f)) {
n += 4;
i >>= 4;
}
if (!(i & 0x03)) {
n += 2;
i >>= 2;
}
return (i) ? (n + ((i+1) & 0x01)) : 0;
#else
/* linear search -- slow, but small */
int n;
for (n = 0 ; i ; ++n) {
i >>= 1;
}
return n;
#endif
}
libc_hidden_def(ffs)
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