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This article is entirely S/360 specific, although the concept of an ADCON applies to most other architectures. I'd like to see it more general, and also mention position-independent code. I'm not sure how to begin changing the article, given it's present IBM-specific nature. Peter Flass (talk) 17:52, 14 September 2018 (UTC)[reply]

I was about to say the same thing. Well, I found this page looking for something about Q-type address constants, and wondering if other systems have something similar. I am pretty sure that other systems have more usual address constants, though it might be that some only do it as part of an instruction. Well, on the PDP-10, at least for the DEC assemblers, the right half of an instruction word looks pretty much like, and is treated much like, an OS/360 address constant. Is it only OS/360 that calls them address constants? (Especially when they might not be constant, as they can get relocated.) Some might just call them addresses, or maybe pointers? There was discussion somewhere also about the complicated relocation system of some DEC assembler. I am not against the examples being OS/360, but we really should get some others in the article. Gah4 (talk) 16:32, 16 September 2022 (UTC)[reply]

As I just wrote in Talk:Relocation (computing), there are no articles for external symbol or relocation dictionary, both needed to explain address constants, and specifically to generalize them from the OS/360 centric description here. The idea of external symbol is needed to explain those that are resolved later, and relocation dictionary to describe the way that different systems do (at least) link time relocation. Now, OS/360 is slightly unusual in the need for both link time and program fetch relocation. Some time ago, in discussing OS/360 relocation factors, someone explained the even more complicated system for DECs RSX-11. It seems that RSX-11 allows much more complicated relocation than the relocation factors of -1, 0, 1, and 2 that OS/360 allows. I am sure that there are more systems that I don't know about, that could also be added to the explanations. Gah4 (talk) 12:45, 23 January 2024 (UTC)[reply]