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Date: Thu, 30 Nov 2017 22:17:13 +0100
From: Szabolcs Nagy <nsz@...t70.net>
To: musl@...ts.openwall.com
Subject: Re: remquo - underlying logic

* Damian McGuckin <damianm@....com.au> [2017-12-01 07:29:05 +1100]:
> It is on MY own TO-DO list. I was asking the question in case anybody had
> done it before and found it useless, could think of major pitfalls, or had
> any pearls of wisdom before we started.  I will keep you posted.

well, one of the difficulties is to get correct behaviour
in case of fenv access (e.g. remquo has exact result in
all rounding modes so intermediate results should be exact
too, raising underflow correctly is sometimes nontrivial,
getting the sign right when the result is zero in downward
rounding mode sometimes needs special handling, etc),
if you need to save/restore the fenv to achieve that then
it's unlikely to be faster than using ints, otherwise floats
are probably faster, but it's hard to tell.

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