Back in the day, I'd have coded something like
LA R7,MYDATA-MYHEAD(,R7) Skip hdr (ref. macro MYSTUFF)
Which at least provides reasonable hints on the reason, and where the value
should be changed.
This still exposes code that didn't use the macro, but that's hard to do
anyway.
Roops
---
"Mundus sine Caesaribus"
On Sun, 24 Aug 2025, 23:20 Seymour J Metz, <[email protected]> wrote:
> The real problem is it does not explain *why* you are adding NOTB to R7.
>
> This gets especially nasty when it is something volatile, eg., set by
> regulations and statutes that change periodically.
>
> --
> Shmuel (Seymour J.) Metz
> http://mason.gmu.edu/~smetz3
> עַם יִשְׂרָאֵל חַי
> נֵ֣צַח יִשְׂרָאֵ֔ל לֹ֥א יְשַׁקֵּ֖ר
>
>
>
>
> ________________________________________
> From: IBM Mainframe Assembler List <[email protected]> on
> behalf of Paul Gilmartin <[email protected]>
> Sent: Sunday, August 24, 2025 5:31 PM
> To: [email protected] <[email protected]>
> Subject: Re: Execute-Type Instructions
>
>
> External Message: Use Caution
>
>
> On 8/24/25 13:51, Seymour J Metz wrote:
> > ...
> > One caveat s that a comment that does not improve understanding is a
> hindrance, and I've warned students that I'll take of points for a comment
> like
> >
> > LA R7,666(,R7) Add 666 to register 7
> >
> > Instead explain why you are adding that value to that register.
> > ...
> And even when a predecessor aimed to do the right thing
> but missed:
> BEAST EQU 666 See Revelation 13:18
> LA R7,BEAST(,R7) Add 666 to register 7
>
> ...when I needed to change the Number of the Beast, I needed
> to modify not only the EQU but also the comment on the LA.
>
> --
> gil
>
>
>
