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SubjectRe: [RFC] x86: bitops asm constraint fixes
Jan Beulich wrote:
>
> That's not very desirable: For one part, because there are uses of
> bitops on arrays of ints (and casting these up isn't fully correct on
> x86-64 because of the same reason that using the bitops on char
> arrays isn't correct (see the other response I sent to Jeremy's reply),
> but also because operating on longs requires REX prefixes n x86-64,
> hence making the code bigger for no good reason.
>

It might be worthwhile to find out if 64-bit bitops are faster.

Bitops are normally defined only on longs, but since x86 is a
littleendian architecture we sometimes fudge that in arch-specific code.

-hpa


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