[llvm] [PEI][PowerPC] Fix false alarm of stack size limit (PR #65559)

[Nemanja Ivanovic via llvm-commits]

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@@ -2740,3 +2740,17 @@ bool PPCFrameLowering::enableShrinkWrapping(const MachineFunction &MF) const {
     return false;
   return !MF.getSubtarget<PPCSubtarget>().is32BitELFABI();
 }
+
+uint64_t PPCFrameLowering::getStackThreshold() const {
+  // On PPC64, we use `stux r1, <scratch_reg>, r1` to extend the stack;
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nemanjai wrote:

I believe this would be `stdux r1, r1, <scratch_reg>` since it is RA that is updated.

https://github.com/llvm/llvm-project/pull/65559