[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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@@ -1104,6 +1104,9 @@ def CC_X86 : CallingConv<[
 
 def CSR_NoRegs : CalleeSavedRegs<(add)>;
 
+def CSR_IPRA_32 : CalleeSavedRegs<(add EBP, ESI)>;
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FreddyLeaf wrote:

They are BasePtr used in x86 frame lowering. https://github.com/llvm/llvm-project/blob/7a086e1b2dc05f54afae3591614feede727601fa/llvm/lib/Target/X86/X86RegisterInfo.cpp#L77 Currently, I don't know how to create an IR to explicitly use BasePtr, if anyone give a hint, it would be appreciated. 

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