[Simh] VAX vectors

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On Thu, 09 Jul 2015 14:53:21 -0600
Richard <legalize at xmission.com> wrote:

> 
> In article <559EBE8A.2010307 at softjar.se>,
>     Johnny Billquist <bqt at softjar.se> writes:
> 
> > On 2015-07-09 20:26, Eric Smith wrote:
> > > Would anyone mind posting a short assembly snippet of a VAX vector
> > > instruction used in context?
> > >
> > > The only complex instruction I've ever used is the Z-80's "LDIR".
> > 
> > Even plain old VAX instructions can be way more complex than LDIR. :-)
> > There are instructions for polynomial expansion, case instructions,
> > move translated strings, and I can't even remember what else...
> 
> VAX was pretty much the last CISC-y architecture that sold in any
> sizable units, AFAIK.

IBM z/Architecture is still a multibillion dollar a year seller. It's
certainly the oldest CISC architecture still in production and active
development. As far as sizeable units go, you may be right. IBM has been
careful not to release numbers but we can often guesstimate from product
license counts and the IBM financials.

I think you could argue at the beginning System/360 did have things in
common with what would later be called RISC although z/Architecture has
overshadowed a lot of that RISC flavor in favor of more specialized
instructions and addressing modes.

There are manuals for the Vector Facility for System/370 on bitsavers in
case anybody is interested in how Big Blue did it. The earliest one I saw
was from 1986. Although I worked on several machines that had the vector
facility I did not use it since I was mostly not working with numerical
applications.

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