Subject: Re: fpu-less duo 210
To: Dan Kelson <kelson@ucolick.org>
From: Colin Wood <cwood@ichips.intel.com>
List: port-mac68k
Date: 09/12/1997 16:59:13
Dan Kelson wrote:
> 
> i've been running netbsd on my duo 210 and, despite the claims for
> fpu emulation, the no-fpu libraries that one gets with netbsd do
> not have all of the functions defined within. many of them are
> just set to unity, presumably because no one wanted to write source
> code for those functions. this makes it difficult to actually write
> useful code. one never knows if sin(X) is always going to be equal
> to 1, or what. i couldn't find anything on the web pages which would
> suggest that things might have been fixed/changed.

Ah, you've hit the dark underside of the current FPE :-)  When the
fpu-less math library was written and FPE, I think that the main purpose
was to implement all those functions to the extent that normal NetBSD
usage wouldn't cause 'unimplemented instruction' errors.  I believe that
only the simple (i.e. non-transcendtal) fp instructions like add,
subtract, and multiply are fully implemented.

> does anybody know?

Ken Nakata would know for sure, since he's the one who did both most of
the FPE and the fpuless math lib.  I think that you can reach him at
kenn@eden.rutgers.edu

I hope this helps some.

Later.

-- 
Colin Wood                                 cwood@ichips.intel.com
Component Design Engineer - MD6                 Intel Corporation
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I speak only on my own behalf, not for my employer.