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To: Paul.Zimmermann@loria.fr (Paul Zimmermann)
Subject: Re: Paul Zimmermann: changing rounding mode on Alpha with gcc 
In-reply-to: Your message of "Wed, 17 Feb 1999 17:44:33 +0100."
             <199902171644.RAA03746@leopold.loria.fr> 
Date: Wed, 17 Feb 1999 19:21:05 +0100
From: Torbjorn Granlund <tege@matematik.su.se>

  I once thought I had found a bug, but it was only the peculiar rounding
  to nearest rule when we are just in the middle of two machine number,
  where we round to the even lsb instead of rounding to infinity as we do
  in math.

Been there...  ;-) Note that it is simple to get this right with a single
logical expression.  Perhaps this code,

    roundup = (((m >> (EXP_BITS - 1)) & 1)
               & (((m & STICKY_MASK) != 0) | ((m >> EXP_BITS) & 1)));

from my P754 library shows the idea.

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