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Date: Fri, 10 Mar 2017 07:02:22 -0600
From: Segher Boessenkool <segher@kernel.crashing.org>
To: Michael Ellerman <mpe@ellerman.id.au>
Cc: Christophe Leroy <christophe.leroy@c-s.fr>,
 Benjamin Herrenschmidt <benh@kernel.crashing.org>,
 Paul Mackerras <paulus@samba.org>, Scott Wood <oss@buserror.net>,
 linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] powerpc: sysdev: cpm1: Optimise gpio bit calculation
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On Fri, Mar 10, 2017 at 07:41:33PM +1100, Michael Ellerman wrote:
> Well yeah, it saves one instruction, but is it worth it? Are these gpio
> routines in some hot path I don't know about?

If there was a GCC PR for this we probably would make GCC optimise
this; there are many similar things that are optimised already, just
not this one.


Segher