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From: perkins@bnrmtv.UUCP (Henry Perkins)
Newsgroups: comp.misc
Subject: Re: Assembly language (was: Re: Another 1.3 wish.)
Message-ID: <2334@bnrmtv.UUCP>
Date: Tue, 4-Aug-87 16:52:44 EDT
Article-I.D.: bnrmtv.2334
Posted: Tue Aug  4 16:52:44 1987
Date-Received: Fri, 7-Aug-87 06:31:15 EDT
References: <8707190424.AA10158@cogsci.berkeley.edu> <434@sugar.UUCP> <1016@sol.ARPA>
Organization: BNR Inc., Mountain View, California
Lines: 29
Summary: Assembly coding is also needed when your goal is overly ambitious

In article <1016@sol.ARPA>, ken@rochester.arpa (Ken Yap) writes:
> In one of his Programming Pearls columns, Jon Bentley asks
> the reader to estimate the cost in programmer wages of "improving" a
> program by bit twiddling vs the cost of the CPU, etc, resources saved.
> 
> I suspect only heavily used programs like the kernel, compilers and
> editors will pass this test. I know most of my programs wouldn't pass.

There's a class of programs that require assembly coding without
necessarily passing the Bentley test; that's when your software
goal is ambitious and your hardware choices are constrained.  The
constraint is generally marketing if the program is much cheaper
than the hardware it's to run on.

My example of this class of programs is Championship Golf, a game
I co-wrote.  I achieved real-time animation on a PCjr, which is
analogous to pushing a Cessna to Mach 1.  This tour de programming
wasn't worth the extra year of code tweaking and algorithm
rethinking it required; it would have been a better economic move
to require a faster processor to run the game on.  However,
marketing the program became MUCH easier if the program could be
advertised as running on any PC compatible with a color display,
rather than just on those with an 8 MHz 8088 or faster processor.
The less efficient program wouldn't have made it to market at all.
-- 
{hplabs,amdahl,3comvax}!bnrmtv!perkins        --Henry Perkins

It is better never to have been born.  But who among us has such luck?
One in a million, perhaps.