[llvm] [aarch64] XOR the frame pointer with the stack cookie when protecting the stack (PR #161114)

[Eli Friedman via llvm-commits]

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@@ -28965,7 +28965,25 @@ void AArch64TargetLowering::ReplaceNodeResults(
 bool AArch64TargetLowering::useLoadStackGuardNode(const Module &M) const {
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efriedma-quic wrote:

I'd prefer not to disable useLoadStackGuardNode; it provides additional protection because it prevents later optimizations from incorrectly hoisting the address computations.

You can add the EOR instruction in AArch64InstrInfo::expandPostRAPseudo.

https://github.com/llvm/llvm-project/pull/161114