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Re: Userland emulator

On 03/26/2013 12:45 AM, Johnny Billquist wrote:
The VVAX (Virtual VAX) addes three instructions (WAIT, PROBEVMR and PROBEVMW), adds one bit to the PSL (telling it's executing in virtual mode), and changes the behaviour of a lot of stuff if you are in virtual mode, as well as having a fake PSL for the virtual machine.
The wait instruction should maybe be added to the idle loop in NetBSD to help emulators know when the machine is idling. On real hardware it do not matter whether takes fault while doing nothing anyway :-)

-- Ragge

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