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Date: Thu, 21 Dec 2017 15:11:30 +0100
From: Peter Zijlstra <peterz@infradead.org>
To: David Laight <David.Laight@ACULAB.COM>
Cc: "'Crt Mori'" <cmo@melexis.com>, Jonathan Cameron <jic23@kernel.org>,
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        Joe Perches <joe@perches.com>
Subject: Re: [PATCH v10 1/3] lib: Add strongly typed 64bit int_sqrt
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On Thu, Dec 21, 2017 at 01:56:55PM +0000, David Laight wrote:
> > This part above looks like FLS
> It also does the rest of the required shifts.

Still, fls() + shift is way faster on hardware that has an fls
instruction.

Writing out that binary search doesn't make sense.