[patch, commited] Do not prefetch loops that do not roll

Richard Guenther rguenther@suse.de
Fri Mar 2 09:03:00 GMT 2007


On Thu, 1 Mar 2007, Zdenek Dvorak wrote:

> Hello,
> 
> this patch makes us avoid issuing prefetches in loops that are finished
> in less time than what the prefetch instruction takes (such prefetches
> are obviously useless, and only would introduce unnecessary overhead).
> 
> Bootstrapped & regtested on i686 (without -fprefetch-loop-arrays, as
> the bootstrap with -fprefetch-loop-arrays currently fails because of the
> warnings introduced by the "compile time array subscript checking" patch),
> commited.

Do you happen to have a testcase (or remember the file that triggered
the warning)?

Thanks,
Richard.



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