[llvm] [X86][IPRA] Add getIPRACSRegs since frame registers are risked to be optimized out. (PR #109597)

[Freddy Ye via llvm-commits]

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@@ -489,6 +489,12 @@ class TargetRegisterInfo : public MCRegisterInfo {
   virtual const MCPhysReg*
   getCalleeSavedRegs(const MachineFunction *MF) const = 0;
 
+  /// Return a null-terminated list of all of the callee-saved registers on
+  /// this target when IPRA is on. Normally, this list should be null.
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FreddyLeaf wrote:

Thanks review! addressed in https://github.com/llvm/llvm-project/pull/109597/commits/ef0f2682c9d8866a2a1fb552cb5941dbf416be56.

https://github.com/llvm/llvm-project/pull/109597