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    SubjectRe: jump/alignment considerations
    >>>>> "mlehmann" == Marc Lehmann <> writes:

    mlehmann> Since lea (%eax),%eax's are used to create 2-7 byte nops,
    mlehmann> removing any alignment will significantly reduce AGI's,
    mlehmann> too, which is probably why the pentium is not getting
    mlehmann> slower (it actually gets a slight advantage).

    gas 2.7 generates suboptimal padding bytes, but this could be fixed.
    For a two byte NOP gas emits `lea (%esi),%esi', when it could use
    `movl %esi,%esi' and avoid the possibility of an AGI stall. For some
    larger pads it puts two lea's back to back *both using %esi*, which is
    non-pairable and causes a guaranteed AGI stall.


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