[llvm] [llvm-exegesis] Begin replacing unsigned with MCRegister. NFC (PR #123109)

[Min-Yih Hsu via llvm-commits]

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@@ -46,7 +46,7 @@ struct RegisterAliasingTracker {
 
   // Construct a tracker from an MCPhysReg.
   RegisterAliasingTracker(const MCRegisterInfo &RegInfo,
-                          const MCPhysReg Register);
+                          const MCRegister Register);
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mshockwave wrote:

> I want to add an assertion for that, but NVPTX and WebAssembly don't compile to traditional assembly and have their own virtual register space

I have been wondering why virtual registers are allowed while the comments in MCRegister's header file say it's for physical registers. Thanks for the clarifications.

https://github.com/llvm/llvm-project/pull/123109