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    SubjectRe: [PATCH 7/8] i386: bitops: Kill needless usage of __asm__ __volatile__
    On Mon, 23 Jul 2007, Jeremy Fitzhardinge wrote:

    > I'm not quite sure what your point is.

    Could be a case of terminology confusion ...

    > The paragraph you quoted is
    > pretty explicit in saying that volatile doesn't prevent an "asm
    > volatile" from being interspersed with other code, and the example just
    > before that is explicit in talking about how to use dependencies to
    > control the ordering of asm volatiles with respect to surrounding code.

    Yes, that was the (2).

    > In fact nothing in that section precludes asm volatiles from being
    > reordered with respect to each other either; you just have to make sure
    > your dependency constraints are all correct.

    The (3) as I had originally written / meant was that multiple
    instructions in a volatile asm would not get _individually_
    interspersed with the rest of the code i.e. be emitted out
    _consecutively_. I don't think we need any such guarantees for
    the non-atomic variants of those operations, so it's good to
    let the compiler have a free hand with what it wants to do,
    and optimize/combine multiple bitops as necessary / possible,
    which was the original intention.

    Satyam
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