gcc loop unrolling problem ??

[Robert Dewar]

Matt Fago wrote:

> My code contains quite a few simple loops with 9 iterations. While I'm 
> surprised that gcc doesn't attempt to completely unroll these, I do 
> agree that doing so will not necessarily improve performance.

What's important to realize is that unrolling such a loop fully may
well *degrade* performance by increasing I-cache pressure without
any compensating gain.