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Re: New Vax - future directions :-)



On 2021-07-06 00:29, Jason Thorpe wrote:

On Jul 5, 2021, at 3:17 PM, Johnny Billquist <bqt%update.uu.se@localhost> wrote:

On 2021-07-05 23:03, Jason Thorpe wrote:
On Jul 5, 2021, at 12:18 PM, Mouse <mouse%Rodents-Montreal.ORG@localhost> wrote:


It clears R0 and R1.  On VAX-32, that is.  It remains to be determined
what it would do on VAX-64 (in 64-bit mode, if the hardware is to be
dual-mode).  Personally, I would say it should clear just R0 (but all
64 bits of it).
IMO, CLRQ should be disallowed in 32-bit mode.

I think you are about 45 years late for that one. :-D

Ok, let me re-state… “for any Q insn that does not already exist, trying to use it in 32-bit mode should cause an illegal insn fault”.

The idea that an operation that takes a single register as an argument would operate on two is, frankly, stupid.

Fair enough. But CLRQ already exists. So it's too late for that one.
Same with MOVQ

But I think those are the only ones defined that I can think of.

  Johnny

--
Johnny Billquist                  || "I'm on a bus
                                  ||  on a psychedelic trip
email: bqt%softjar.se@localhost             ||  Reading murder books
pdp is alive!                     ||  tryin' to stay hip" - B. Idol


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