Path: utzoo!utgpu!news-server.csri.toronto.edu!rutgers!usc!sdd.hp.com!hplabs!hpda!hpcupt1!jamiller
From: jamiller@hpcupt1.HP.COM (Jim Miller)
Newsgroups: comp.lang.misc
Subject: Re: Fortran (or anything else) is efficient?
Message-ID: <6000009@hpcupt1.HP.COM>
Date: 14 Jul 90 00:37:31 GMT
References: <2306@l.cc.purdue.edu>
Organization: Hewlett Packard, Cupertino
Lines: 46


>>I understand that Fortran 90 is eliminating or restricting some of the useful,
>>but not much used, features of Fortran considered bad by language gurus. 
>>The use of an ASSIGNED goto, especially without list, can make life 
>>difficult for the automatic optimizer, but it can sure speed up a program.
>
>They also make life hell for the poor bastard who gets stuck maintaining
>a program that some efficiency freak coded.  Assigned gotos are an
>abomination, and anybody who uses one should be flogged around the public
>square at high noon.
>
>  -- David Wright, not officially representing Stardent Computer Inc
>     wright@stardent.com  or  uunet!stardent!wright
>
>Actually, I didn't want to *gently* chide Jake.  I wanted to castrate
>him and run his balls up the flagpole to see if anyone saluted them. 
>Besides Jake.  -- Jack Douglas
>----------

Ah, it's nice to live in a world were it will not make any difference whether
or not your program takes 1 day or 10 days of CRAY time just so the
maintainer will not have to keep the documentation/comments up to date.

However, some of us are forced to live in the world and our products will
be used by people who, when faced with a program that takes 100 minutes to do a
function that a competitors does in 10 minutes, will pick the 10 minute model
-- despite the increased difficulty of the competitors to support their
program.  Ah, the indignities we force on others because we love to eat,
sleep, and continue to work -- and make the customer happy.

Seriously, "unsupportable" constructs HAVE been known to improve performance
by a factor of 5 to 10.  Often they CAN be maintained -- by proper use of
comments & tools & documentation.

Having said that.  May I attend the flag raising for those who do
unsupportable "optimizations" as a matter of course.  Making the 80% of
the code that does 20% of the work as difficult a support task as any other
piece of code -- like the 2% that does 50% (I've seen some).

And yes, I do realize that the first avenue of attack should be the algorithm.
(and the second and the third).

    jim - without the Mimimum Acceptable Level of Performance,
	  you don't have a product  - miller
    My company doesn't know I have these opinions, let alone approve of them.
    jamiller@hpcupt1.cup.hp.com