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From: jbs@WATSON.IBM.COM
Newsgroups: comp.arch
Subject: Re: Implementing Interval Arithmetic with IEEE rounding modes
Message-ID: <9106190427.AA02284@ucbvax.Berkeley.EDU>
Date: 19 Jun 91 04:22:54 GMT
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         David Hinds said:
Really, it seems to me that if support for interval arithmetic is built
into a compiler, it should be able to optimize away most of the rounding
mode changes without too much trouble.  This should be trivial for the
cases where the mode changes would otherwise do the most damage, such as
in tight inner loops with no dependencies, i.e., vector operations.  Just
split and do two loops, one for the lower and one for the upper vectors.

         I believe if you try to do this with
      DO 10 J=1,N
   10 X(J)=Y(J)*Z(J)
         you will discover things are not so simple.
                       James B. Shearer