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Subject: Re: [PATCH v2 22/25] powerpc32: move xxxxx_dcache_range() functions
 inline
From: Scott Wood <scottwood@freescale.com>
To: Christophe Leroy <christophe.leroy@c-s.fr>
CC: Joakim Tjernlund <joakim.tjernlund@transmode.se>, "paulus@samba.org"
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Date: Tue, 22 Sep 2015 17:52:33 -0500
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On Wed, 2015-09-23 at 00:49 +0200, Christophe Leroy wrote:
> Le 23/09/2015 00:34, Scott Wood a écrit :
> > On Tue, 2015-09-22 at 22:57 +0200, Christophe Leroy wrote:
> > > > Here is what I get in asm. First one is with "if (i) mb();". We see 
> > > > gcc
> > > > puts a beqlr. This is the form that is closest to what we had in the
> > > > former misc_32.S
> > > > Second one if with "mb()". Here we get a branch to sync for a useless 
> > > > sync
> > I was more concerned with keeping the code simple than the asm output.
> > 
> Right, but is that so complicated to say: if we did nothing in the loop, 
> no need to sync ?

As I said, it doesn't matter very much.  I wouldn't put it in personally, but 
it's not worth a long discussion.

-Scott