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    SubjectRe: [patch 1/13] Qsort
    Date
    On 23 Jan 2005, at 03:39, Andi Kleen wrote:

    > Felipe Alfaro Solana <lkml@mac.com> writes:
    >>
    >> AFAIK, XOR is quite expensive on IA32 when compared to simple MOV
    >> operatings. Also, since the original patch uses 3 MOVs to perform the
    >> swapping, and your version uses 3 XOR operations, I don't see any
    >> gains.
    >
    > Both are one cycle latency for register<->register on all x86 cores
    > I've looked at. What makes you think differently?

    I thought XOR was more expensie. Anyways, I still don't see any
    advantage in replacing 3 MOVs with 3 XORs.

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