[llvm] [Exegesis][RISCV] Add RISCV support for llvm-exegesis (PR #89047)

[Craig Topper via llvm-commits]

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@@ -86,6 +86,11 @@ class ExegesisTarget {
                 ArrayRef<const char *> ValidationCounters,
                 const pid_t ProcessID = 0) const;
 
+  // Find register by name, NoRegister if not found.
+  virtual MCRegister findRegisterByName(const StringRef RegName) const {
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topperc wrote:

Where is this used?

https://github.com/llvm/llvm-project/pull/89047