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Re: SPARC condition-code question



On Tue, Jul 14, 2020 at 12:53:30 -0400, Mouse wrote:

> I'm working on a SPARC emulator, and have run into a question:
> 
> Is it true the only way to have condition code bits N and Z set
> simultaneously involves help from privileged code (specifically,
> wrpsr)?  I have found short (<= 3 instruction) simple sequences to
> generate all 12 of the other combinations, but it looks to me as though
> getting N and Z set together requires wrpsr.

I would guess so, as a combination of N and Z would indicate a result
that is both negative and zero.

-uwe


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