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    SubjectRe: [RFC] x86: bitops asm constraint fixes
    >>> "H. Peter Anvin" <> 14.03.08 08:51 >>>
    >Jan Beulich wrote:
    >> I'd really like understand, though, what the policy of (not) having a
    >> "memory" clobber in these operations is - currently, this appears to
    >> be totally inconsistent. Also, many comments of the non-atomic
    >> functions say those may also be re-ordered - this contradicts the use
    >> of "asm volatile" in there, which again I'd like to understand.
    >In general, proper "m" constraints are better than "memory" clobbers,
    >since they give gcc more information. Note that the "m" constraint
    >doesn't actually have to be *manifest* in the assembly string.

    ... which is the case with the patch applied.

    So am I taking this as 'yes, a proper re-write of these routines is
    worthwhile'? But - you didn't comment on the other issues raised,
    so before getting to that I'll have to wait to see what's the reason
    (if any) for the other anomalies.


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