[llvm] [aarch64] Mix the frame pointer with the stack cookie when protecting the stack (PR #197346)

[Pan Tao via llvm-commits]

PanTao2 wrote:

I’m very sorry for the error (0xc0000409 is STATUS_STACK_BUFFER_OVERRUN (Security check failure or stack buffer overrun)) introduced by the previous CL (https://github.com/llvm/llvm-project/pull/161114). Thanks @luporl  for reverting it.
The error was caused by me using “add” instruction (SP + (SP - cookie) = 2 * SP - cookie, wrong) not “sub” instruction (SP - (SP - cookie) = cookie, correct) in the failure BB. I have fixed the errors in this CL. @efriedma-quic Could you please review this CL? Thank you in advance.
@zmodem I’m very sorry for blocking your work, could you please try this CL before re-landing it?

https://github.com/llvm/llvm-project/pull/197346