Not just the separation, but even to the extent of getting you to work
with us.
ItIS almost impossible to get your interests up. And, it works
both ways. Itls almost impossible to get my hardware people interested
in working with you. So, I sit back and I say this, every time I see the
to base your entire existence upon extending things that were obsolete
when you started, I think is to avoid the issue of why we Ire doing an
-McGonagle: My name is Dave McGonagle, and I'm an english major, and I come from Burroughs Corporation, where hardware and software types exist on the same design team. The last two machines to come out of Burroughs have had, amazingly enough, a software man as a Program Manager. We do design machines with compilers in mind ..• As far as background is concerned, incidentally, I started in this business in 1951 at Wright Field, on CPC 's, if there's anyone around who can re-member them, and passed through the university computer environment as an applications programmer, and passed from there to Westinghouse with SOLOMON, and eventually to parallel proceSSing and then wound up at Burroughs. I've known Bruce for a number of years. We've lived together, you might say, trying to get a multiprocessing operating system to work. Currently, I've just completed an as signment to design an
avionic multiprocessor implementation in LSI, and we're now going to go ahead and build it. But, Mr. Nimensky said earlier about the transfer-ability from the 360 to the SPECTRA ... I'd like to remind you that the RCA people forgot something. You don't transfer software unless you also transfer the operating system interface. Therefore, 360 programs do not run on the SPECTRA 70. No one can guarantee OS 360 interface, unles s they're willing to run OS 360 •.• A problem raised here ..• the FORTRAN machine .•• A FORTRAN machine couldn't begin to solve the problem, because FORTRAN, itself, as a language, would not be satis-factory. We've built, in the last eight years, machines specifically designed for two different languages. The 5500, in which the machine language was reversed Polish, essentially the intermediate language put out by practically everybody's compiler. It was geared toward ALGOL.
We've come out with a 3500, which is geared toward COBOL. I'm sure, if the Navy bought enough of them, we would come out with a different machine geared to CMS-2, or another one geared to SPL. They wouldn't be the same machine. They don't come out the same .•• Trouble with idiotic things, like COBOL's requirement that you don't store the result of an arithmetic operation until after you know there's no overflow. This causes you to design an adder that goes from left to right instead of right to left. Clever. Saves you a little time. Saves some memory space. Lots of little things like this happen. Reversed Polish ..• for
that we implemented an automatic index register operation called a "stack."
If someone asked me if the 5500 had an index register, I'd have to say,
-when we can give you a different machine for each language. At this machine description to another. Your machine for, essentially, direct execution of algorithmic statements, I expect, by the end of the year in memory. Who, in their hardware, has built addressing algorithms
for list structures. Who, in their hardware, has built addres sing algorithms for trees. Yet those of you who are interested in information retreaval
systems had better get interested in that problem. The AADC machine only incidentally is going to work in the F-14, just as incidentally is the airborne multiprocessor for Wright Field going to work in a bomber,
-company to go this way, i. e. (microprogramming), it just happened LSI years people argued that you couldn't measure the instruction utilization of a computer because you could only measure them statically. Well,
shalt execute 250 thousand instructions/second. What in the hell does that mean? Can anyone tell me? We go back to the original statement
-per processor! If I can harness it ••• This is no longer funny. This is bucks you're throwing away ••• You guys, when you write these specs, have patience with people who have questions to ask. Because, some of us have questions concerning the organizations of the computers we're building. The ILLIAC IV came into existence because of people like that you've incorporated the recognition that a programmer works with a total system, but there's a hell of a lot missing from your system, be-cause until a programmer works interactively, he never really has use of your library. He can't really build a procedure by asking what he did, which detected the procedure that had been declared but not yet written.
That remembered the subroutine that you thought you were going to write, that was only four lines long, that you hadn't done. All this belongs
in that debugging package as well. I") think you should seriously consider the addition of simulators. Being a'software man turned hardware designer, I brought a little different background into this thing. I lived through the cases for. Because, invariably, they're conditional. The thought of that, and the thought of being the pilot of the F-lS up there on terrain following radar scared the living hell out of me. I think it might be cheaper, even if it cost more, to buy the memory without GOTOs. However, I'm
not saying it will. Bruce and I learned a lesson together. Programs
182
-should be small. They -should be logical. And, any program with more than 50 ALGOL - like statements in them are too damn long. I have been
preaching this. Alan Baxter when on his 5500 at Virginia last year decided to find out what the world of students looked like. Lo and behold, the average segment in his system was 30 statements long. So, this is not unreasonable; There's a university doing all their programming, and
the average segment is only 30 instructions long. Turns out data segments aren't much longer. And, this turns out not to be too different from those figures IBM has leaked out about their paging problems. That under
200 instructions were being executed on the model 67 between page calls.
And it took 700 instructions to satisfy the page call. That's a snicker, but that's a triviality, which can be fixed. What can't be fixed is the ignoring of that 200 instruction limit. What can't be fixed is that people want to hold on to old thing s like GOTO' s and JUMP's. It would have
been very little trouble for you in CS-2 to have made the programs reentrant.
I think it would also be worth your while to take a look if you really want multiple entry and exit pOints. All these things add to the problems of debugging, checking out and validating the modules. Now, Deichster with three other people wrote a multiprogramming operating system and check it out. Now I other than key punching errors, it ran the first time it was on the hardware. It is impossible for there to be any unexpected event in that system. Logically inconsistant for it to be. There is no program module larger than a single logical event, and every module is debugged logically. Now, we can build hardware that will do this .••
I think that is about what I have to say.
Wald: Surely, there must be an argument.
Deerfield: They're overwhelmed.
Wald: Will Dave then ... I hate to give you the floor again, but you said something which seemed a little inconsistant. You said that different languages would imply different machines ••• The ALGOL machine, the COBOL machine, and so forth ... but you also said they would have dif-ferent bells and whistles; but you also said the compilers and compiler writers aren't taking advantage of the bells and whistles you already have on the machine. Now, these stupid compiler writers are going to have to become microprogrammers. Are they going to be any smarter?
McGonagle: Where did I say that, Bruce? The small number of instruc-tions that are used?