Re: [PHP-DEV] str_repeat() patch

[Michael Walter]

Well, surely memmove() needs an additional branch to check for 
overlapping, though (the OP was wrong in that memmove() would need a 
temporary buffer, though - it doesn't, it usually copies from high 
addres to low in the overlapping case).

Cheers,
Michael
George Schlossnagle wrote:
On Jun 12, 2004, at 10:27 AM, Alexander Valyalkin wrote:
On Fri, 11 Jun 2004 17:00:03 +0200 (CEST), Derick Rethans 
<[EMAIL PROTECTED]> wrote:

On Fri, 11 Jun 2004, Alexander Valyalkin wrote:
Read it:
void *memmove(void *s1, const void *s2, size_t n);
If s1 and s2 overlap, all bytes are copied in a preserving manner 
(unlike
memcpy())

And anwer the question: are s1 and s2 overlap in the str_repeat() ?
Why don't use memcpy() instead of memmove() ?

Because it's slower and we're copying to newly allocated memory anyway
so things CAN not overlap. Also, your patch is the wrong way around.
Mybe I'm mistaken, but I think, that memmove() looks like that (without
any error checks):

That's not what my glibc sources look like.
George
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