Path: utzoo!utgpu!attcan!uunet!lll-winken!lll-tis!ames!ncar!oddjob!uxc!uxc.cso.uiuc.edu!a.cs.uiuc.edu!p.cs.uiuc.edu!gillies
From: gillies@p.cs.uiuc.edu
Newsgroups: comp.arch
Subject: Re: using (ugh!  yetch!) assembler
Message-ID: <76700043@p.cs.uiuc.edu>
Date: 27 Jul 88 22:07:00 GMT
References: <2926@utastro.UUCP>
Lines: 30
Nf-ID: #R:utastro.UUCP:2926:p.cs.uiuc.edu:76700043:000:1468
Nf-From: p.cs.uiuc.edu!gillies    Jul 27 17:07:00 1988


In article jbs@fenchurch.mit.edu.UUCP (Jeff Siegel) writes: 
>This just isn't true.  There are an aweful lot of real live products,
>and BIG ones, that have been built in assembly language.  Have you
>read _The_Mythical_Man-Month_?  5000 man-years it did take, but OS/360
>was a whole bunch of assembly code (millions of lines, minimum) that
>has probably made IBM billions.
>
>I write a 25000 line assembly program (for a class) about 4 years ago
>that was well organized, documented, etc.  I have no doubt that it
>could be modified and maintained today (or 10 years from now).

Do you realize you have hung yourself by proclaiming OS/360 as a
triumph of assembly language?  "The Mythical Man Month" is not a
gothic romance -- it is a horror story.

OS/360 had over 50,000 UNFIXABLE documented bugs, partly because
fixing some bugs would introduce even more bugs (buggy code relied on
buggy code).  I suspect some bugs were not fixable because of the
difficulty of modifying the assembly code.

If you want to cite a SUCCESSFUL system that uses assembly language,
how about the No 1. ESS switching system from AT&T (3 million lines)?
AT&T once offered me a job working on that system.  They had 10
scientists just STUDYING THE FEASIBILITY of making modifications to
the assembly code!


Don Gillies, Dept. of Computer Science, University of Illinois
1304 W. Springfield, Urbana, Ill 61801      
ARPA: gillies@cs.uiuc.edu   UUCP: {uunet,ihnp4,harvard}!uiucdcs!gillies