*BSD News Article 2698


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From: merlin@neuro.usc.edu (merlin)
Newsgroups: comp.unix.bsd
Subject: 386BSD-0.1/BRLCAD4.0 benchmark -- poor floating point performance
Message-ID: <l7ctu0INN880@neuro.usc.edu>
Date: 29 Jul 92 10:49:36 GMT
Article-I.D.: neuro.l7ctu0INN880
Sender: merlin@neuro.usc.edu (merlin)
Organization: University of Southern California, Los Angeles, CA
Lines: 13
NNTP-Posting-Host: neuro.usc.edu

It looks like the floating point processor is used for simple floating
point operations (+, -, /, *) but not for higher functions -- these go
to /usr/src/lib/libm/ieee/support.c where they get emulated (ie _sqrt)
very slowly.  Perhaps someone has a redistributable i386 library which
could be plugged in place of the default 4.3BSD mathematics library.

This is likely why BRLCAD 4.0 runs correctly but very slowly at the
present time.  Any help or suggestions which would fix this problem
would be very much appreciated.  

Does gcc 2.2 actually use 80387 inline code for transcedental functions?

Thanks, AJ