Path: utzoo!utgpu!watmath!clyde!att!rutgers!tut.cis.ohio-state.edu!bloom-beacon!bu-cs!purdue!i.cc.purdue.edu!k.cc.purdue.edu!l.cc.purdue.edu!cik
From: cik@l.cc.purdue.edu (Herman Rubin)
Newsgroups: comp.arch
Subject: Re: Assembly or ....
Summary: Nor is there an integer quotient, and some machines do not even have
	 a quotient
Message-ID: <1036@l.cc.purdue.edu>
Date: 1 Dec 88 11:22:56 GMT
References: <1388@aucs.UUCP> <729@convex.UUCP> <1961@crete.cs.glasgow.ac.uk> <2061@garth.UUCP>
Organization: Purdue University Statistics Department
Lines: 16

In article <2061@garth.UUCP>, smryan@garth.UUCP (Steven Ryan) writes:
> >I can't think of a machine that doesn't. The only machine language
> 
> 6600/Cyber 170, Cyber 205 don't return the remainder, nor is there a mod
> instruction.

On both of these machines, the division must be done in floating point and
the quotient converted to integer, etc.  On the CRAYs, division does not even
exist--a reciprocal must be computed, and then a floating point quotient, etc.
Since the machines are scoreboarded, a mod operation not tying up the hardware
should be spread over some 50 instructions for the 6600 or CRAY and 75
instructions on the 205 to be efficient.
-- 
Herman Rubin, Dept. of Statistics, Purdue Univ., West Lafayette IN47907
Phone: (317)494-6054
hrubin@l.cc.purdue.edu (Internet, bitnet, UUCP)