Re: 80286 protected mode

According to Anton Ertl <anton@mips.complang.tuwien.ac.at>:

If you look at the 8086 manuals, that's clearly what they had in mind.
>
What I don't get is that the 286's segment stuff was so slow.

>
It had to load the whole segment descriptor from RAM and possibly
perform some additional setup.

Right, and they appeared not to care or realize it was a performance problem.

They didn't even do obvious things like see if you're reloading the same value
into the segment register and skip the rest of the setup. Sure, you could put
checks in your code and skip the segment load but that would make your code a
lot bigger and uglier.

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