Path: utzoo!utgpu!news-server.csri.toronto.edu!rutgers!mit-eddie!uw-beaver!uw-june!robertb
From: robertb@cs.washington.edu (Robert Bedichek)
Newsgroups: comp.sys.m88k
Subject: Re: floating point exceptions
Message-ID: <13899@june.cs.washington.edu>
Date: 29 Nov 90 10:42:23 GMT
References: <1990Nov29.084840.5410@Neon.Stanford.EDU>
Reply-To: robertb@june.cs.washington.edu (Robert Bedichek)
Organization: University of Washington, Computer Science, Seattle
Lines: 33

In article <1990Nov29.084840.5410@Neon.Stanford.EDU> sean@Neon.Stanford.EDU (Sean Quinlan) writes:
>I am trying to code a simple exception handler for the two floating
>point exceptions.  The 88100 manual states that there are routines from
>Motorola that do the default IEEE processing.  Has anyone used these?

Yes, they are in the Tektronix and Motorola kernels, as well as at
least one Mach port that I know of.  My guess is that they are in
everyone's 88k kernel.

>Are they public domain?  If not, does anyone have any code they can give

I doubt that they are in the public domain.  I suggest that you ask
Moto's MCD (Microcomputer Division) in Tempe Az. for them.  Maybe
they'll just give them to you.  They were originally developed by the
chip folks in Austin Texas, but my guess is that it is no maintained
in Tempe.

>me?  I probably do not need full IEEE conformance, just enough so that
>resonable results are produced when I start running out of precision instead
>of taking the exception and crashing.  Having code to do the right thing
>with infitity, NaN etc would be nice but not essential.

They do all sorts of things besides obscure IEEE conformance.  Like,
they fix up floating to integer conversions that sometimes trap even
when the operand is not out of range.

This code is all in assembly and very tricky.  I highly recommend that
you get it from Motorola.

>Many thanks
>sean quinlan

	Rob Bedichek   robertb@cs.washington.edu