Sender: derrick AT tapir DOT Caltech DOT EDU
Message-ID: <378F9D37.EC6D3B6B@cco.caltech.edu>
Date: Fri, 16 Jul 1999 13:59:35 -0700
From: Derrick Bass <derrick AT cco DOT caltech DOT edu>
Organization: Caltech
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To: pgcc AT delorie DOT com
Subject: Do underflows cause a slowdown? Can I fix it?
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Reply-To: pgcc AT delorie DOT com

I am using a Pentium Pro (180 MHz, Redhat 5.2) and some of my FP
intesive code occassionally slows by a factor of 4-6.  I think I've
traced this to underflow. . .

Does handling underflow slow down floating point?  Is there a compiler
switch or library call to make the underflows silently get replaced by
zero?

I am not on the mailing list, so please reply to me personally as well
as to the list.

Thanks for any help!

Derrick Bass