Maamoun TK maamoun.tk@googlemail.com writes:
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.
Hmm. I agree just lowering the stack pointer sounds a bit questionable. But if we use some other register to point into the protected zone, we should be fine? E.g.,
addi r10, r1, -0x40 C Save callee-save registers stvx v20, 0, r10 stvx v21, r6, r10 stvx v22, r7, r10 stvx v23, r8, r10
Regards, /Niels