[PATCH] Use memcpy in memmove when possible

H.J. Lu hjl.tools@gmail.com
Sat Sep 1 12:52:00 GMT 2012


On Sat, Sep 1, 2012 at 1:16 AM, Maxim Kuvyrkov <maxim@codesourcery.com> wrote:
> Several architectures, e.g., MIPS, have well-optimized memcpy implementations, which can also be used for either forward or backward direction in memmove.  This patch adds an option for ports to define MEMCPY_OK_FOR_{FWD,BWD}_MEMMOVE macros to make generic memmove use memcpy when safe to do so.
>
> This patch speeds up forward-direction memmove on MIPS by 50%.  Tested with no regressions.
>

If memcpy is safe for memmove, you can simply make memmove an alias of
memcpy in memcpy source.  Why do you need to update string/memmove.c?


-- 
H.J.



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