3 ms·
> Trap the undefined instructions, and dynamically replace them with a jump to emulation code if running on a little core. This was more or less what VMware pi
by jacques_chester 6y ago
> Trap the undefined instructions, and dynamically replace them with a jump to emulation code if running on a little core.
This was more or less what VMware pioneered to deal with privileged instructions. I expect there are thickets of patents involved, even if the earliest have expired. But it's likely there is or would be some licensing agreement.
Disclosure: I work for VMware, though not in VMs per se. Speaking for myself only.
- jdsully 6y agoThis is how FPU emulation worked back in the 8086-386 days. Any patents are long expired or invalidated with prior art.
- garmaine 6y agoNo, unfortunately not. Only if you implement it exactly as it was done back in the day for FPUs. Any deviation and you might run into a more recent patent that covers some aspect of a later implementation, maybe even something seemingly obvious or necessary. This is why it is called a patent “minefield.”