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    SubjectRe: Big git diff speedup by avoiding x86 "fast string" memcmp
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    Nick Piggin:
    > It's not scaling but just single threaded performance. gcc turns memcmp
    > into rep cmp, which has quite a long latency, so it's not appripriate
    > for short strings.

    Honestly speaking I doubt how this 'long *' approach is effective
    (Of course it never means that your result (by 'char *') is doubtful).
    But is the "rep cmp has quite a long latency" issue generic for all x86
    architecture, or Westmere system specific?


    J. R. Okajima


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