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    SubjectRe: [BK+PATCH] remove __constant_memcpy

    On Thu, 17 Apr 2003, Jeff Garzik wrote:
    >
    > __constant_memcpy was used for small, constant-sized cases AFTER
    > the kernel made the decision not to hand the copy duties over to the
    > kernel's MMX/SSE code. Take a look at the bottom of the patch below,
    > and also this snip from a non-hacked string.h, for illustration...

    This is the part I don't like

    #define memcpy(t, f, n) \
    (__builtin_constant_p(n) ? \
    - __constant_memcpy((t),(f),(n)) : \
    + __builtin_memcpy((t),(f),(n)) : \
    __memcpy((t),(f),(n)))

    Notice? Our old __constant_memcpy() would do the rigth thing for large
    copies. In conrast, I don't know that gcc will do so.

    Linus

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