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From: Denis Vlasenko <vda@port.imtp.ilyichevsk.odessa.ua>
To: Grzegorz Kulewski <kangur@polcom.net>
Subject: Re: [PATCH] Make gcc -align options .config-settable
Date: Fri, 8 Oct 2004 23:42:40 +0300
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Cc: Andi Kleen <ak@muc.de>, linux-kernel@vger.kernel.org
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On Friday 08 October 2004 17:30, Grzegorz Kulewski wrote:
> > Also bencmarking people may do little research on real usefulness of
> > various kinds of alignment.
> 
> I think that removing aligns completly will be very bad. I am Gentoo user 
> and I set my user space CFLAGS for all system to -falign-loops 
> -fno-align-<everything else>. I did not tested it in depth, but my simple 
> tests show that unaligning loops is a very bad idea. Unaligning functions 

That depends on how often that loop runs. 90% of code runs only
10% of time. I think ultimately we want to mark other 10% of code with:

int __hotpath often_called_func()
{
...
}

Rest of code is to be optimized for size.

> is safer since small and fast functions should be always inlined.

Concept of alignment does not apply to inlined functions at all.
--
vda

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