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    Subject[PATCH 0/3] lib/int_sqrt: Fix, optimize and document
    Hi,

    Here are a few patches that should improve things lib/int_sqrt. As stated
    elsewhere; I'm looking at using int_sqrt() to calculate the stdev on a normal
    distribution and am expecting the input values to be smallish.

    In any case, these optimizations should work fine for large numbers too. And
    if you have a find-last-set or count-leading-zeros instruction they rock ;-)

    I can post the tool used to generate the numbers or do a patch to add it to
    tools/testing/ if people care. The cold numbers are fairly sensitive to code
    layout (GCC version, random changes etc..), so I expect the branch predictor of
    my SKL is only partially confused or there's other things at play. However the
    general trend in the numbers seems fairly stable.

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