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Subject: Re: [patch V3] lib: GCD: add binary GCD algorithm
From: Geert Uytterhoeven <geert@linux-m68k.org>
To: George Spelvin <linux@horizon.com>
Cc: Andrew Morton <akpm@linux-foundation.org>,
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On Thu, Apr 28, 2016 at 6:48 PM, George Spelvin <linux@horizon.com> wrote:
> Another few comments:
>
> 1. Would ARCH_HAS_FAST_FFS involve fewer changes than CPU_NO_EFFICIENT_FFS?

No, as you want to _disable_ ARCH_HAS_FAST_FFS / _enable_
CPU_NO_EFFICIENT_FFS as soon as you're enabling support for a
CPU that doesn't support it.

Logical OR is easier in both the Kconfig and C preprocessor languages
than logical NAND.

E.g. in Kconfig, a CPU core not supporting it can just select
CPU_NO_EFFICIENT_FFS.

Gr{oetje,eeting}s,

                        Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds