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Date: Wed, 27 Jul 2011 08:12:00 -0000
From: Paolo Bonzini <bonzini@gnu.org>
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To: Xinliang David Li <davidxl@google.com>
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Subject: Re: [RFC] Remove -freorder-blocks-and-partition
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On 07/27/2011 06:51 AM, Xinliang David Li wrote:
> >  If we could retain most of the speedups when the optimization works well
> >  but avoid most of the slowdown in the benchmarks that are currently hurt,
> >  we could improve the overall SPEC06 score.  And hopefully, this would
> >  also be beneficial to other code.
>
> Agree.  There are certainly problems in the partition pass, as for
> bzip2 the icache misses actually go up with partition, which is not
> expected. It needs further analysis.

It's probably too aggressive.  Icache misses go up because a) the 
overall size of the executable grows; b) cold parts are probably not 
cold enough in the case of bzip2.f

Paolo