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    SubjectRe: [PATCH] optimize ia32 memmove
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    On Tue, 2003-12-30 at 01:58, Linus Torvalds wrote:
    > But then anything that does the loads in ascending order is still ok, so
    > it shouldn't matter - by the time "dest" has been overwritten, the source
    > data has already been read. And all the "memcpy()" implementations had
    > better do that anyway, in order to get nice memory access patterns. "rep
    > movsl" certainly does.

    A PPC memcpy may end up clearing the destination before reading the
    source (using the cache-line zeroing instruction, to prevent the
    destination from being spuriously read to populate the cache line).

    J

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