Path: utzoo!mnetor!uunet!lll-winken!lll-lcc!pyramid!csg From: csg@pyramid.pyramid.com (Carl S. Gutekunst) Newsgroups: comp.arch Subject: Re: For a good time, read... Message-ID: <18567@pyramid.pyramid.com> Date: 6 Apr 88 02:39:49 GMT References: <7841@apple.Apple.Com> Organization: Pyramid Technology Corp., Mountain View, CA Lines: 25 In article <7841@apple.Apple.Com> bcase@Apple.COM (Brian Case) writes: >There is a wonderful article in EE Times this week. Starting on page 49 >and continuing on page 54, the article, entitled "CISC beats RISC in test," >sumarizes the results of a battery of tests performed by Neal Nealson & >Associates. I have not seen the article; I am familiar with the Neal Nelson benchmark and would not take seriously any conclusions drawn from it. The code is written to be "unoptimizable." What this means is that is is com- pletely non-structured -- FORTRAN with semicolons, vast runs of intertangled "if () goto" and labels, no locality to speak of. Totally contrary to normal C programming methodology, and surely a nightmare for the instruction cache. Far worse, it uses *NO* local variables. Everything is declared static. This kills machines that depend on storing frequently-used variables in registers (and do not have register allocation in the loader). In both cases -- no locality, no automatic variables -- the benchmark is using constructs that RISC architects have determined (correctly) are not typically used in "real" code. No wonder the RISC machines come out looking bad! (Disclaimer: These are my personal observations, which have no relationship to the opinions of Pyramid Technology, and are based almost entirely on hearsay.)