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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
Date: Fri, 10 Mar 2017 07:02:22 -0600	[thread overview]
Message-ID: <20170310130222.GG31469@gate.crashing.org> (raw)
In-Reply-To: <87a88tle0y.fsf@concordia.ellerman.id.au>

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

      parent reply	other threads:[~2017-03-10 13:06 UTC|newest]

Thread overview: 10+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2017-03-09  9:42 [PATCH] powerpc: sysdev: cpm1: Optimise gpio bit calculation Christophe Leroy
2017-03-10  8:41 ` Michael Ellerman
2017-03-10 10:54   ` Christophe LEROY
2017-03-10 13:06     ` Segher Boessenkool
2017-03-10 14:04       ` Christophe LEROY
2017-03-10 14:32         ` Segher Boessenkool
2017-03-10 14:41           ` Christophe LEROY
2017-03-10 15:41             ` Segher Boessenkool
2017-03-21 15:04               ` Christophe LEROY
2017-03-10 13:02   ` Segher Boessenkool [this message]

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