[llvm] [AArch64][SME2] Add FORM_STRIDED_TUPLE pseudo nodes (PR #116399)

[Sander de Smalen via llvm-commits]

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@@ -8641,6 +8646,55 @@ static bool checkZExtBool(SDValue Arg, const SelectionDAG &DAG) {
   return ZExtBool;
 }
 
+bool shouldUseFormStridedPseudo(MachineInstr &MI) {
+  MachineRegisterInfo &MRI = MI.getMF()->getRegInfo();
+  bool UseFormStrided = false;
+  unsigned NumOperands =
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sdesmalen-arm wrote:

`NumOperands` is only used to define `RegClass`. It seems better to create a switch-statement that sets `RegClass`, and has an `llvm_unreachable` for any unsupported opcodes.

https://github.com/llvm/llvm-project/pull/116399