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Re: [RFC] Fix PR19401: always completely peel loops


> From: Andrew Pinski <pinskia@physics.uc.edu>
>> On Jan 13, 2005, at 1:51 PM, Paul Schlie wrote:
>>> Richard Guenther writes:
>>> This minimal patch unconditionally enables complete loop peeling
>>> at the tree level.
>> 
>> Isn't it rather presumptuous to assume that such a thing is universally
>> beneficial to all targets?
>> 
>> (as would expect it to predominantly result in bloated code for smaller
>> lightly pipelined targets, with little if any tangible benefit; unless
>> I
>> misunderstand?)
> 
> Yes, which is why there should be constraint on when this should be
> done, only do it for -O2/-Os when it reduces the number of
> instructions (usually also size but at this point we don't
> know the size) and do it fully at -O3.

And there are no other optimizations enabled at -O3 which may be desired,
without unconditionally also fully peeling loops?



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