Subject: Re: INSN_EMULATION
To: Anders Magnusson <ragge@ludd.luth.se>
From: David Brownlee <abs@netbsd.org>
List: port-vax
Date: 09/04/2000 08:58:43
On Sat, 26 Aug 2000, Anders Magnusson wrote:

> > > Reverse polarity on INSN_EMULATION to NO_INSN_EMULATION.  Thus by default
> > > all kernels will have instruction emulation.
> > 
> > 	Would it make sense to conditionalise this based on the CPU?
> > 
> This was recently changed not to compile it conditionally on per-CPU
> basis :-) The reason is that there are very few VAX CPUs that have all
> possible instructions available, and this is on a per-installation
> basis, not per-CPU-type basis.
> 
> The only CPU type I know that had all instructions available as standard
> was the 11/730, and that CPU isn't supported by NetBSD :-)

	Ah :)
	Do emulated instructions tend to be needed in specific groups,
	such that splitting up INSN_EMULATION would make sense (though
	INSN_EMULATION could include all). Just trying to shave a few
	bytes for those 4MB users :)

                David/absolute
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