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From: jcallen@Encore.COM (Jerry Callen)
Newsgroups: comp.sys.m88k
Subject: Re: Fixed point multiply overflow detection
Summary: $#@ brain-damaged chip!
Message-ID: <12438@encore.Encore.COM>
Date: 9 Aug 90 16:22:28 GMT
References: <1990Aug08.182206.22187@unx.sas.com>
Reply-To: jcallen@encore.com (Jerry Callen)
Organization: Encore Computer Corp, Marlboro, MA
Lines: 15

In article <1990Aug08.182206.22187@unx.sas.com> sasrer@mozart.unx.sas.com (Rodney Radford) writes:
>Does anyone know how to check if an overflow occurs with the MULT instruction?

Grrrrrrr.....

There are several bits of brain damage in the 88k, but this one takes the
cake. As Jeff Kenton points out, your choices are to just convert to
floating point and do your multiplication that way or to manually check
the magnitudes. Both suck.

Has anyone seen specs for the 88110? Is a fix for this stupidity going
to be available in the next generation of the 88k?

-- Jerry Callen
   jcallen@encore.com