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

[Min-Yih Hsu via llvm-commits]

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@@ -235,7 +237,7 @@ static cl::opt<std::string>
 static cl::opt<std::string>
     MCPU("mcpu",
          cl::desc("Target a specific cpu type (-mcpu=help for details)"),
-         cl::value_desc("cpu-name"), cl::cat(Options), cl::init("native"));
+         cl::value_desc("cpu-name"), cl::cat(Options), cl::init(""));
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mshockwave wrote:

I kind of knowing why you made this change here, but I think it's better to leave it `native`.

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