Xref: utzoo comp.arch:10323 comp.sys.dec:1429
Path: utzoo!attcan!utgpu!jarvis.csri.toronto.edu!rutgers!tut.cis.ohio-state.edu!purdue!avr
From: avr@cs.purdue.EDU (Andrew V. Royappa)
Newsgroups: comp.arch,comp.sys.dec
Subject: Re: DECStation vs. SPARCstation, need help!
Summary: integer multiply and divide on Sun 4
Message-ID: <6976@medusa.cs.purdue.edu>
Date: 20 Jun 89 19:12:07 GMT
References: <486@unipas.fmi.uni-passau.de> <1094@syma.sussex.ac.uk>
Followup-To: comp.arch
Organization: Department of Computer Science, Purdue University
Lines: 23

In article <1094@syma.sussex.ac.uk>, aarons@syma.sussex.ac.uk (Aaron Sloman) writes:
> Our (informal) comparisons between Sun3/280 and Sun4/260 running
> Poplog (see below) show that on balance the latter is between 1.5
> and 2 times faster. On simple Poplog Prolog tests the Sun4 is fairly
> consistently around twice as fast. But integer multiplication (e.g.
> factorial(1000)) is slightly faster on Sun3/280! (On Sun386i it was
> faster still, though other things were slower.)
> 

I noticed that multiply and divide on my Sun 4/110 were not as fast
as I expected them to be. Disassembling the code showed that integer
multiplication and division were actually not done in hardware, but as
subroutine calls to library routines.

Just out of curiosity, why doesn't the Sun 4/110 not have hardware
integer multiply and divide ? Is this part of the "RISC" concept ?

				Thanks,

					Andrew Royappa
					Purdue University
					{ihnp4,pur-ee}!purdue!avr
					avr@purdue.edu