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From: firth@sei.cmu.edu (Robert Firth)
Newsgroups: comp.arch
Subject: Re: 88k trick for FP abs/neg
Message-ID: <6160@aw.sei.cmu.edu>
Date: 8 Jul 88 15:34:37 GMT
References: <10136@tekecs.TEK.COM> <2553@obiwan.mips.COM>
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In article <10136@tekecs.TEK.COM>, andrew@frip.gwd.tek.com (Andrew Klossner)
writes
	> To clear up a question: on the 88k, floating point values are
	> kept in general registers, so "abs" is done by ANDing to 0 the
	> sign bit, "neg" is done by XORing the sign bit, and "mov" is
	> done with conventional register-to-register move instructions.

Ho boy! The last time I saw a compiler XOR the sign bit of floating zero
must have been about 1975.  Old bugs never die, they just migrate to new
hosts.