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

[Aiden Grossman via llvm-commits]

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@@ -168,7 +168,15 @@ void BasicBlockFiller::addInstruction(const MCInst &Inst, const DebugLoc &DL) {
     } else if (Op.isImm()) {
       Builder.addImm(Op.getImm());
     } else if (!Op.isValid()) {
-      llvm_unreachable("Operand is not set");
+      std::string Message;
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boomanaiden154 wrote:

This addition here looks unrelated (directly at least) to the RISCV support? Maybe pull this out into a separate patch?

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