Re: freezes when not emulating CPU

[Stas Sergeev <stsp@aknet.ru>]

18.09.2009 00:37, Samuel Bronson wrote:
> Well, I believe that's essentially what Intel suggests OSes do on
> task-switch -- leave some flag set/cleared that will cause the next FP
> operation to give an exception so that it can switch the FP registers
> at that time. Whether or not this would be a good idea for DOSEMU
> depends on how often you do a vm86 call vs how often the FP registers
> are needed, and on how expensive it is to actually enter a state from
> which the next FP access will cause a signal compared to just doing
> the reload each time.
dosemu is not interrupted by the DOS
code, so the full reload is never really
needed. You just need the "known good state",
rather than the "full previous state".
If whatever is needed is only fninit/ldmxcsr,
then I guess it is just cool.