ffs.h

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#ifndef _ASM_GENERIC_BITOPS_FFS_H_
#define _ASM_GENERIC_BITOPS_FFS_H_

static 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;
}

#endif /* _ASM_GENERIC_BITOPS_FFS_H_ */