I'm sure that's the reason why the extended mnemonics have not traditionally
been in there.  But, as a mere user, I don't give a rat's ass about the
internecine conflicts between the business divisions of IBM; I care only about
how easy it is to access the information I need. Where they /deserve/ to be
documented is where they make most sense from a usability standpoint.

And, as you so rightly point out, if they can put in the basic mnemonics, they
/why not/ the go go the whole hog and clearly document the extended as well?

i

------ Original Message ------
Received: 05:34 PM COT, 12/23/2013
From: Paul Gilmartin <[email protected]>
To: [email protected]
Subject: Re: Latest PoO available?

> On 2013-12-23, at 14:37, Ian S. Worthington wrote:
> >
> > Just seen this.  So it is!
> >
> > Never seen that before. Have the architecture folks finally understood
that
> > the PoO is the main reference manual for coders, not the HLASM manuals,
and
> > quietly slipped it in the corner?  Don't think they need to be /quite/ so
> > reticent about it!
> >
> Clearly, the extended mnemonics are features not of the hardware,
> but of the assembler, and deserve to be documented not with the
> former, but with the latter.
>
> But can't the same be said of the basic mnemonics?  After all,
> the hardware defines only the binary opcodes; all else might be
> considered properly the realm of software documentation.  The
> design should be based, however, on what's reasonable and useful.
>
> Originally, the operation code consisted of only the first 8
> bits of any instruction; bits elsewhere could be considered
> modifiers of a single operation code with a single mnemonic
> chosen by the hardware designers.  Nowadays, that's far from
> true.
>
> To muddle things further, the organization of the PoO implies
> that the various associated RX, RR, SS, and SI forms are deemed
> variants of a single instruction (but with distinct mnemonics).
> Notwithstanding, regrettably, many releases ago the PoP outgrew
> the capacity of Bookie and has since been available only in PDF.
> I suppose it might just be considered ahead of its time.
>
> -- gil

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