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Re: New Vax - future directions :-)

On 2021-07-06 08:46, Anders Magnusson wrote:
Den 2021-07-05 kl. 23:03, skrev Jason Thorpe:
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.
Well, CLRQ is actually the same as CLRD/CLRG, so it can't be disallowed :-)
Remember that floating point spans multiple registers as well.

However, MOVQ and MOVD are not the same.

But in general, there are some needs to deal with data quantities that are larger than 32 bits, and there are obviously times when you only want to do it in registers, so what would you do if you don't link multiple registers together?


Johnny Billquist                  || "I'm on a bus
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