[llvm] [AArch64][SME] Conditionally do smstart/smstop (PR #77113)

[Matthew Devereau via llvm-commits]

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@@ -208,6 +208,8 @@ class AArch64FunctionInfo final : public MachineFunctionInfo {
 
   int64_t StackProbeSize = 0;
 
+  Register PStateSMReg = MCRegister::NoRegister;
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MDevereau wrote:

Done

https://github.com/llvm/llvm-project/pull/77113