Re: Ada and Automotive Industry

[Richard Riehle <rriehle@nunic.nu.edu>]

On Wed, 27 Nov 1996, Ken Garlington wrote:

> The only problem with this argument is that it applies to _many_
> real-time embedded systems, not just those based on the 8051. Some of those
> systems have been successfully programmed in Ada. In fact, the memory and
> throughput efficiency of some Ada implementations has been shown to be very
> close to assembly code generated by the average assembly programmer. It won't
> be until someone actually posts some detailed notes describing the success or
> failure of a port before we know whether or not such a port can be done.

  No argument with the fundamentals of this comment.  You and I are
  familiar with the successes of Ada on the 1750A.  This is a far
  different animal from the 8051.  I agree that the issue will not
  be settled unlesss someone does the port (or builds a compiler
  from scratch).

> >   As to porting GNAT ... [snipped stuff]

> Probably because no one has invested sufficient time and energy to
> attempt a highly-optimized implementation. Such implementations take
> extensive work on _any_ embedded platform.

  I said earlier this would be a daunting task, not an impossible one.
  Is a good investment for anyone.  My view is that this would make
  a good research project for a graduate student somewhere.  Probably
  be in the interest of someone like Aonix or Rational or DDC-I to
  make some nominal contribution to such a graduate research project.

> Of course, if "many others" do not see a market for 8051s, then I think you
> just answered your own question as to why you don't see any attempts to
> do a GCC port!

  I mean, "many others" in the Ada industry.  There are FORTH, Modula,
  PLM, C, BASIC and other languages for the 8051.  

> I get ESP as well, and I see several "C" compilers advertised for the 8051.
> Doesn't this fly in the face of your earlier argument that most programmers
> would rather use assembly? For that matter, if "C" is commercially feasible,
> based on the number of ads, why not Ada (or at least an Ada subset)? There's
> certainly published experience that Ada compilers can outperform "C" compilers.

  Many 8051 programmers even refuse to use C because it is too inefficient
  for their needs.  Certainly, one can ascribe some of that intransigence
  to the elitism characteristic of those who program only in assembler.
  But another aspect is the need for constraining applications to a
  minimally configured 8051.

> The existence of MIL-STD-1750A Ada compilers, IMHO, is due to the large 
> investment of a small number of large corporations in such technology. I don't
> expect to see such a sizable investment in the future (although I'd like to
> be proven wrong!) for any processor.

  I agree.  And I hope we are both proven wrong.

  Richard Riehle