On Mon, May 27, 2002 at 08:53:02AM +0000, Pavel Machek wrote:
> Hi!
>
> > I would be (pleasantly) surprised to see gcc turn a C memcpy into faster
> > assembly than our current implementation. And I'll bet
>
> gcc has hand-coded assembly inside itself, if gcc compiled memcpy is slower
> than hand-optimized one, you found a compiler bug.
Not at all. gcc compiled memcpy just has no knowledge of things like
non-temporal stores, and using mmx/sse to move 64 bits at a time instead
of 32 bit registers. (It's only recently it got prefetch abilities too).
-- | Dave Jones. http://www.codemonkey.org.uk | SuSE Labs - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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