On Tue, 2 Sept 2025 at 07:22, Binyamin Dissen <
00001773bcccb823-dmarc-requ...@listserv.uga.edu> wrote:

> You can teach an old dog new tricks.
>
> I never knew about this and used the PUSH approach below.
>

I probably knew of it from other contexts if I thought about it, but it
wouldn't have been top of mind.

On that note, I imagine few people looking at that explicit 0 index
register would know why it's there (and might be tempted to "fix" it as
part of a code review/cleanup), so I'd suggest a concise comment on each
usage. Something like "Explicit 0 index to avoid alignment msg".

Tony H.

On Tue, 2 Sep 2025 20:10:29 +1000 Peter Morrison
> <0000160d7dfdc207-dmarc-requ...@listserv.uga.edu> wrote:
>
> :>Hello,
> :>
> :>              Has anyone else used (0) at the end of an RX (or RXY)
> instruction to suppress the assembler's alignment check?
> :>
> :>              For Example:
> :>
> :>                              DC X'00'        force next field to be
> unaligned
> :>              X_UNAL  DC AL4(0)       Declare an unaligned fullword
> :>
> :>                              L       R0,X_UNAL
>  gets a warning
> :>                              L       R0,X_UNAL(0)
> same generated code (ix reg is 0) but no warning
> :>
> :>              If so, where is it documented? (this is easier than a
> <PUSH ACONTROL/ACONTROL NOALIGN/instr/POP ACONTROL> sequence (and takes no
> extra lines))
> :>
> :>Peter Morrison
>
> --
> Binyamin Dissen <bdis...@dissensoftware.com>
> http://www.dissensoftware.com
>
> Director, Dissen Software, Bar & Grill - Israel
>

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