memmove broken

Paul Mackerras paulus at
Fri Jul 4 16:17:21 EST 2003

Joakim Tjernlund writes:

> I just tried to used memmove in zlib(zlib_inflate_fast) to avoid expensive
> byte copies. That didn't work and the reason is that the ppc memmove can handle
> overlapping memory it seems.

I assume you mean "can't handle"?

If so, this is interesting because it is supposed to work. :)

> memmove(dst, dst-x, n) where x is between 1 and 39, n >= x will cause corruption for me.

Gack.  It should be using backwards_memcpy in arch/ppc/lib/string.S.
I'll have to take a look at it.


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