[patch] Nontemporal prefetches

[Zdenek Dvorak]

Hello,

> > this patch makes us issue nontemporal prefetch instructions (prefetchnta
> > on x86) to prefetch memory references that provably are not reused in L2
> > cache.  We do this only for loop nests that process data that do not fit
> > entirely in L2 cache (since we do the reuse analysis only locally to the
> > loop nest, we cannot know otherwise whether the contents of the L2 cache
> > is not reused later).
> > 
> 
> How will this feature be enabled?

it is run by default with -fprefetch-loop-arrays.

Zdenek