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From: jbs@WATSON.IBM.COM
Newsgroups: comp.arch
Subject: float/float = integer, remainder
Message-ID: <9105130317.AA09926@ucbvax.Berkeley.EDU>
Date: 13 May 91 02:49:53 GMT
Sender: daemon@ucbvax.BERKELEY.EDU
Lines: 16


          Herman Rubin states:
                                              I have already pointed out
that every trigonometic and exponential routine does, in some way,
float/float -> integer, remainder.  The integer is also used.

          1.  As I have already pointed out, the actual computation being
done is float/real -> integer, remainder (since pi and ln(2) are not ma-
chine numbers).  A proposed float/float -> integer, remainder instruc-
tion (assuming it ran at the same speed as floating divide, actually it
would probably be slower) would not benefit the trigonometric or
exponential routines on any architecture I am familiar with
          2.  In any case it is not true that "every" exponential routine
does this computation.  The scalar short precision exp routine in IBM's
vs fortran library does not do this computation in any way.
                       James B. Shearer