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    SubjectRe: [PATCH] bitops: add 8-bit and 16-bit rotation functions
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    >>> +/**
    >>> + * rol16 - rotate a 16-bit value left
    >>> + * @word: value to rotate
    >>> + * @shift: bits to roll
    >>> + */
    >>> +static inline __u16 rol16(__u16 word, unsigned int shift)
    >>> +{
    >>> + return (word << shift) | (word >> (16 - shift));
    >>> +}
    >>
    >> This doesn't work for shift values of 0: you get word >> 16, and
    >> shifts greater than or equal to the word size aren't valid C. GCC
    >> will warn about this, too.
    >
    > On the other hand, a value narrower than int will always be promoted
    > first,

    Erm, yes of course. It is promoted to _signed_ int though, but
    that works okay here.

    > so this is not a problem in this case.

    It still needs documentation for the valid values of "shift".


    Segher



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