Re: [PATCH] powerpc: sysdev: cpm1: Optimise gpio bit calculation

From	Segher Boessenkool <segher@kernel.crashing.org>
Newsgroups	linux.kernel
Subject	Re: [PATCH] powerpc: sysdev: cpm1: Optimise gpio bit calculation
Date	2017-03-10 14:10 +0100
Message-ID	<tjssV-4sG-9@gated-at.bofh.it> (permalink)
References	<tj2RP-3lW-7@gated-at.bofh.it> <tjopj-1j2-1@gated-at.bofh.it>
Organization	linux.* mail to news gateway

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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

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[PATCH] powerpc: sysdev: cpm1: Optimise gpio bit calculation Christophe Leroy <christophe.leroy@c-s.fr> - 2017-03-09 10:50 +0100
  Re: [PATCH] powerpc: sysdev: cpm1: Optimise gpio bit calculation Michael Ellerman <mpe@ellerman.id.au> - 2017-03-10 09:50 +0100
    Re: [PATCH] powerpc: sysdev: cpm1: Optimise gpio bit calculation Christophe LEROY <christophe.leroy@c-s.fr> - 2017-03-10 12:00 +0100
      Re: [PATCH] powerpc: sysdev: cpm1: Optimise gpio bit calculation Segher Boessenkool <segher@kernel.crashing.org> - 2017-03-10 14:20 +0100
        Re: [PATCH] powerpc: sysdev: cpm1: Optimise gpio bit calculation Christophe LEROY <christophe.leroy@c-s.fr> - 2017-03-10 15:10 +0100
          Re: [PATCH] powerpc: sysdev: cpm1: Optimise gpio bit calculation Segher Boessenkool <segher@kernel.crashing.org> - 2017-03-10 15:40 +0100
            Re: [PATCH] powerpc: sysdev: cpm1: Optimise gpio bit calculation Christophe LEROY <christophe.leroy@c-s.fr> - 2017-03-10 15:50 +0100
              Re: [PATCH] powerpc: sysdev: cpm1: Optimise gpio bit calculation Segher Boessenkool <segher@kernel.crashing.org> - 2017-03-10 16:50 +0100
    Re: [PATCH] powerpc: sysdev: cpm1: Optimise gpio bit calculation Segher Boessenkool <segher@kernel.crashing.org> - 2017-03-10 14:10 +0100

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