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Date: Sat, 3 Jan 2015 20:37:45 -0800
From: Steve Kargl <sgk@troutmask.apl.washington.edu>
To: Pedro Giffuni <pfg@freebsd.org>
Subject: Re: glibc math improvements
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On Sat, Jan 03, 2015 at 10:00:58PM -0500, Pedro Giffuni wrote:
> 
> This blog post was covered by Phoronix:
> http://developerblog.redhat.com/2015/01/02/improving-math-performance-in-glibc/ <http://developerblog.redhat.com/2015/01/02/improving-math-performance-in-glibc/>
> 
> Not sure any of that stuff is applicable to our implementation but it looks like an interesting link to share nevertheless.
> 

AFAICT, it is not applicable.   The improvements are in
a 768-bit multi-precision computation of pow() to get an
accurate answer.  The article mentions that the technique
may be applied to exp() and log(), but the table-driven
methods that Bruce, David, and I used for logl, expl, and
exp2l are quite accurate (somewhere around ulp < 0.55 or so).

-- 
Steve