Fast SIGNUM equivalent

[jbarnett@charming.nrtc.northrop.com]

I have written a program that incorporates something like

	(CASE (SIGNUM (- I1 I2))
	  (1 ....)
	  (0 ....)
	  (-1 ....))

where I1 and I2 are fairly small, positive integers.  This form is being
executed a lot (hundreds of millions of times).  Is there anyway to
speed up the test-branch part of this enough to justify whatever
pornography is necessary?

Jeff Barnett