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#ifndef FIO_FFZ_H
#define FIO_FFZ_H
static inline int __ffs(unsigned long word)
{
int r = 0;
#if BITS_PER_LONG == 64
if ((word & 0xffffffff) == 0) {
r += 32;
word >>= 32;
}
#endif
if (!(word & 0xffff)) {
word >>= 16;
r += 16;
}
if (!(word & 0xff)) {
word >>= 8;
r += 8;
}
if (!(word & 0xf)) {
word >>= 4;
r += 4;
}
if (!(word & 3)) {
word >>= 2;
r += 2;
}
if (!(word & 1)) {
word >>= 1;
r += 1;
}
return r;
}
static inline int ffz(unsigned long bitmask)
{
return __ffs(~bitmask);
}
#endif
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