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Re: [f-cpu] Smooth Register backup issues...

Hi #2,

Christophe Avoinne wrote:


To be sure to understand what you mean :

- there are two independant register-sets, only one of which  you can
access.

Yes.


- when executing a CMB switching, you just implicitely select the other set
so that old registers can be saved in old CMB context, and we can continue
to run code with the new registers without write-back memory delay penalty.

Exactly.


For interrupt, it may be very interesting if we dont need to read the values
of registers ( the stack pointer is fixed-address at raising interrupt ?
what about the reentrance ? ).

See my other mail.


Still I see a problem : we must preload the values of new registers from the
new CMB context, especially when switching between tasks. How do you plan
that ? have an explicit instruction to reload the new register set ?
That can be done en bloc or on-demand, but in either case it should be done automatically.


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