Talk:NEWP

Memory array M?

I have included my recollections and understanding about the global memory array M and restriction of scope to blocks annotated with UNSAFE (MEMORY). Perhaps someone more familiar with M could confirm that is correct, or modify accordingly. Ian.joyner (talk) 00:13, 16 September 2024 (UTC)

Machine instructions are generated directly from each source statement?

The article claims that "...the machine instructions are generated directly from each source statement."

What does "directly" mean here?

A statement such as a := (b*c) + (d*e*f); would, on a stack machine, generate code with a combination of push, arithmetic, and pop instructions; that's not direct. There's more than one sequence of code that could be generated; for example, it could be compiled into

push b
push c
mul
push d
push e
push f
mul
mul
add
pop a

push d
push e
push f
mul
mul
push b
push c
mul
add
pop a

or into

push d
push e
mul
push f
mul
push b
push c
mul
add
pop a

If your stack machine has two top-of-stack registers, so that up to two stacked operands can be accessed without fetching from memory or a cache, the third of those is the best code, as it only has to spill a top-of-stack register to memory on one occasion (the push c instruction). Even if it has three top-of-stack registers, both the second and third of those are better than the first.

And neither of those are direct images of the code, as NEWP, like most programming languages, uses algebraic notation, not reverse-Polish notation, for arithmetic expressions. Guy Harris (talk) 19:05, 16 October 2024 (UTC)

Good point. It is a bit vague. I have modified the paragraph to "NEWP is closely tied to the features and semantics of the platform and MCP itself. Since this is the case, there has never been a need for assembly language on these systems since ESPOL in 1961, and no assembler is provided, even for internal Burroughs/Unisys use. NEWP (and ESPOL) programmers are familiar with the way the machine works as a stack machine and the instruction set, since each source statement relates closely to the generated machine instructions. This contributes to the platform as a secure multiprocessing system, since general programmers cannot use any assembler and NEWP is itself limited mostly to writing an operating system, particularly the MCP."

The intent of that paragraph is to explain why there is no need for assembler and the security comment also clarified to reflect that since general programming cannot be done either in assembler and not even in NEWP itself for the dangerous facilities.

Does this make it clearer for readers? Ian.joyner (talk) 01:40, 17 October 2024 (UTC)

Again, in what way does "each source statement relates closely to the generated machine instructions"? Programmers may know thet arithmetic and logical (bitwise) operations are evaluated using an evaluation stack, but 1) do they know the exact sequence of operations with which a particular expression (other than, say, a trivial expression with two operands, where it's obviously going to be push, push, operation) will be implemented, or do they just know that it'll be some sequence of pushes and arithmetic operations, and 2) does it matter and do they care what the sequence is? That strikes me as something that's "below the language layer" even for a low-level language. The only place where the particular instructions matter might be UNSAFE code such as the intrinsics that correspond to machine instructions.

As for the security, that sounds as if the "they know what machine code is generated" (to what extent that's true) isn't relevant there, and the part that's relevant is that NEWP in UNSAFE mode is the only place where unsafe code is generated is what matters. (I'm assuming here that some forms of UNSAFE mode code can be executed outside control state, so that, whilst some protection is provided by privileged instructions being executable only in control state, other protection is provided by only allowing "blessed" UNSAFE mode code to be executed at all. If not, then it's just "privileged mode vs. unprivileged mode", as on the other general-purpose computers out there.) Guy Harris (talk) 05:45, 17 October 2024 (UTC)

Specifying how each source statement relates to the generated instructions would be too detailed for an encyclopaedia article where people are coming for general information for background interest, even more so for the introductory section (which is far too long in many WP entries).

The statement is true, which anyone who has used Burroughs system languages will tell you from setting the $list code options.

"1) do they know the exact sequence of operations"

No the sequence does not need to be exact.

"2) does it matter and do they care what the sequence is?"

Actually, less than most other architectures or languages. However, remember NEWP is for writing the MCP OS, not for general programming. In fact, if someone writes a program in NEWP, it won't run without special steps taken securely (which most installations simply would not do).

I don't think the second paragraph is relevant to the discussion or article. Ian.joyner (talk) 08:50, 18 October 2024 (UTC)

Actually, less than most other architectures or languages. So the sequence of operations generated for a NEWP statement matters less than does the sequence of operations generated for ALGOL, DCALGOL, DMALGOL, COBOL, or FORTRAN 77? Or NEWP programmers care less about the generated sequence of operations than do ALGOL, DCALGOL, DMALGOL, COBOL, or FORTRAN 77 programmers?

However, remember NEWP is for writing the MCP OS, not for general programming. Why, except in a tiny number of places, would the exact sequence of operations matter more, or less, for OS programming? I've worked on a fair bit of OS code and rarely, if ever, have had to know or care about the sequence of operations generated by the optimizing compilers used to compile that code. Guy Harris (talk) 18:04, 28 October 2024 (UTC)

DO NOT DELETE THE NEWP ENTRY

I don't know who this Mr HyperAccelerated (MR HA) is, it seems they have nothing to there name on WP apart from this deletion notification.

I thus suspect industry shenanigans. While the reason given is there is little findable online material apart from at Unisys (a full manual available), that is only a weak test, and certainly DOES NOT apply here.

Let's use this test: "On Wikipedia, the general inclusion threshold is whether the subject is notable enough for at least two people to have written something substantive (more than just a mention) about that subject that has been published in a reliable source."

Yes, NEWP has a reliable source at Unisys. Secondly this article has been worked on by multiple people for nearly 20 years.

It may be that Mr HA has no familiarity with this subject so it might seem irrelevant to him, or that Mr HA has some industry axe to grind or works for some competitive concern.

I find the whole 'flag for deletion' suggestion here nonsense in one way or another. Ian.joyner (talk) 00:44, 13 February 2025 (UTC)

If you think I'm being paid for my edits, you are free to go to WP: COIN, though I warn you that any complaint you make without evidence is unlikely to go anywhere. I do not have the time to deal with a user who thinks it's appropriate to SHOUT IN ALL CAPS to get their point across to hardworking volunteers. HyperAccelerated (talk) 00:59, 13 February 2025 (UTC)

I put the heading in capitals because your attempt to delete this article is nonsense.

I do not have time to deal with this nonsense, but it is worthwhile since NEWP is a significant language for OS development, even though it is only used internally in Unisys, since, unlike other system languages, it is ONLY for writing an OS (MCP OS).

That in itself is a significant fact.

I don't know who you are since you hide behind some silly pseudonym, but it seems like you have no WP track record apart from suggesting this.

I do not have time to deal with nonsense. Ian.joyner (talk) 02:06, 13 February 2025 (UTC)

I suggest you read WP: ADHOM (given your propensity to attack my "track record") and WP: GNG (which describes the relevant policy in deletion discussions). These sorts of personal attacks are incivil and may land you in some very hot water. Please proceed carefully. Thanks. HyperAccelerated (talk) 03:57, 13 February 2025 (UTC)

You should stop making threats to people. That is less civil.

I have only called into question your track record with WP and the fact that you post anonymously with a pseudonym.

You said made the point that me putting the headline in caps was shouting. Rather it was for emphasis. Then you said it is aimed at the hardworking volunteers of WP. How about you insulting the volunteers who have worked on this article for over 20 years without complaint or someone trying to flag it as irrelevant before. Ian.joyner (talk) 08:11, 13 February 2025 (UTC)