Re: [MiNT] what's wrong with this code?

[Andreas Schwab <schwab@suse.de>]

Johan Klockars <johan@klockars.net> writes:

> No stack pointer is ever saved before entering an exception handler, nor 
> restored on RTE.
> There are physically separate registers for the various stack pointers, 
> which just get "remapped" in hardware depending on the bits in SR.

But note that when you toggle the S bit in the saved SR you are returning
to a different stack than before.  If USP and SSP are not properly set up
you can end up overwriting part of the other stack that you need when
switching back.

Andreas.

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Andreas Schwab, SuSE Labs, schwab@suse.de
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