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    SubjectRe: [PATCH 7/8] i386: bitops: Kill needless usage of __asm__ __volatile__
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    On Monday 23 July 2007 18:06:03 Satyam Sharma wrote:
    > From: Satyam Sharma <ssatyam@cse.iitk.ac.in>
    >
    > [7/8] i386: bitops: Kill needless usage of __asm__ __volatile__
    >
    > Another oddity I noticed in this file. The semantics of __volatile__
    > when used to qualify inline __asm__ are that the compiler will not
    > (1) elid, or, (2) reorder, or, (3) intersperse, our inline asm with
    > the rest of the generated code.
    >
    > However, we do not want these guarantees in the unlocked variants of the
    > bitops functions.

    I thought so too and did a similar transformation while moving
    some string functions out of line. After that recent misadventure
    I would be very very careful with this.

    Overall I'm sorry to say, but the risk:gain ratio of this
    patch is imho totally out of whack.

    It took a long time to get bitops.h correct and as far as we know
    it is compiled correctly currently. You risk all at for very dubious
    improvements.

    -Andi



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