Messages in this thread | | | From | Kees Cook <> | Date | Fri, 20 Oct 2017 07:18:51 -0700 | Subject | Re: [PATCH] lib/int_sqrt.c: optimize for small argument values |
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On Thu, Oct 19, 2017 at 11:13 PM, Joe Perches <joe@perches.com> wrote: > On Thu, 2017-10-19 at 13:31 -0700, Michael Davidson wrote: >> int_sqrt() currently takes approximately constant time >> regardless of the value of the argument. By using the >> magnitude of the operand to set the initial conditions >> for the calculation the cost becomes proportional to >> log2 of the argument with the worst case behavior not >> being measurably slower than it currently is. > > https://lkml.org/lkml/2017/7/24/408
Ah! Cool. I don't see this version queued up for -next. Where does Peter's version stand?
-Kees
-- Kees Cook Pixel Security
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