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

[Min-Yih Hsu via llvm-commits]

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@@ -291,6 +297,22 @@ T ExitOnFileError(const Twine &FileName, Expected<T> &&E) {
   return std::move(*E);
 }
 
+static const char *getIgnoredOpcodeReasonOrNull(const LLVMState &State,
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mshockwave wrote:

Here: https://github.com/llvm/llvm-project/blob/79643565a890d29560782fea23877ae61ea5b987/llvm/tools/llvm-exegesis/lib/SerialSnippetGenerator.cpp#L58

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