Subject: Re: Emulation pointer wanted
To: None <tech-kern@netbsd.org>
From: der Mouse <mouse@Rodents.Montreal.QC.CA>
List: tech-kern
Date: 09/15/1999 10:17:37
> Once the emulators get sophisticated enough to do dynamic
> recompilation, this technology becomes much more interesting.

I've been considering some kind of JIT compilation to native code,
rather than individually emulating each instruction.

But that most definitely will not be in the first version. :-)

>> I was thinking of doing this as an emulation package in the kernel,
> Yeah.  Note that on at least m68k/i386 there is floating point
> emulation code in the kernel, and on i386 it could really use some
> work.

Not in that sense; I mean "an emulation package" as in "struct emul".
I don't intend to put the foreign-machine-emulator code in the kernel.

>> (a) Emulating the instructions
>> (b) Emulating failure modes
>> (c) Emulating syscalls
>> (d) Getting it started
> Don't forget signal delivery, and debugging would be good to have
> eventually.

I think signal delivery will have to be either blown off or handled by
the emulator, at least until someone manages a much more sophisticated
emulation than what I'm imagining.

					der Mouse

			       mouse@rodents.montreal.qc.ca
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