Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!ncar!ames!oliveb!sun!fatcity!khb
From: khb@fatcity.Sun.COM (Keith Bierman Sun Tactical Engineering)
Newsgroups: comp.arch
Subject: Re: Bandwidth and RISC vs. CISC
Message-ID: <102026@sun.Eng.Sun.COM>
Date: 1 May 89 02:53:59 GMT
References: <38853@bbn.COM> <423@bnr-fos.UUCP> <17417@cup.portal.com> <38971@bbn.COM> <100524@sun.Eng.Sun.COM>
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Reply-To: khb@sun.UUCP (Keith Bierman Sun Tactical Engineering)
Organization: Sun Microsystems, Mountain View
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In article <100524@sun.Eng.Sun.COM> dgh%dgh@Sun.COM (David Hough) writes:
> ... much good reading deleted..

>Not all code is compiled.  For instance, there is a great body of theory
>and practice in obtaining computational error bounds in computations
>based on interval arithmetic.  Interval arithmetic is
>efficient to implement with the directed rounding modes required by IEEE
>arithmetic, but you can't write the implementation in standard C or
>Fortran.  In integer arithmetic, the double-precise product of 
>two single-precise operands,
>and the single-precise quotient and remainder of a double-precise
>dividend and single-precise divisor, are important in a number of
>applications such as base conversion and random number generation,
>but there is no way to express the required computations in standard
>higher-level languages.
>

I believe that the next rev of Fortran (new socially approved
spelling) will allow us to write this sort of code. I also think that
it can be done in Ada.
Keith H. Bierman      |*My thoughts are my own. Only my work belongs to Sun*
It's Not My Fault     |	Marketing Technical Specialist 
I Voted for Bill &    |   Languages and Performance Tools. 
Opus            (* strange as it may seem, I do more engineering now     *)