Newsgroups: comp.arch
Path: utzoo!henry
From: henry@utzoo.uucp (Henry Spencer)
Subject: Re: RISC  a short answer??
Message-ID: <1988May3.224604.2252@utzoo.uucp>
Organization: U of Toronto Zoology
References: <1036@nusdhub.UUCP>
Date: Tue, 3 May 88 22:46:04 GMT

> 	Can someone give me [short answer style] a description
> of what "RISC" means...

Many people confuse things that are often characteristics of current RISC
designs with the fundamental underlying idea, which is:

	Keep the instruction set simple.

Most instructions actually executed are simple even if the instruction set
is complex.  Leaving out the complexity makes it easier to make the simple
stuff fast.  Since the simple stuff accounts for most of the execution
anyway, the result is faster machines.

This is *not* the same as "throw the complexity into the software", since
a simple instruction set frequently makes compilers etc. *simpler*, other
things being equal.
-- 
NASA is to spaceflight as            |  Henry Spencer @ U of Toronto Zoology
the Post Office is to mail.          | {ihnp4,decvax,uunet!mnetor}!utzoo!henry