Re: PPC chacha

On Mon, Nov 30, 2020 at 10:07 PM Maamoun TK maamoun.tk@googlemail.com wrote:

BTW since there is no function called while the register of the stack frame is modified, I think it's fine to not follow the rules and keep the store and restore sequences as are without any modification.

I'm thinking what could happen if an exception raised while the stack frame is modified incorrectly, the exception handler will try to look at the calling function but it can't get the previous state of stack pointer because the stack pointer doesn't point to it and that will mess the exception handling procedure. So we can't ignore the rules whatsoever and we have to modify the stack frame correctly.

regards, Mamone