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

[via llvm-commits]

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@@ -52,7 +52,7 @@ computeAliasingInstructions(const LLVMState &State, const Instruction *Instr,
       continue;
     if (OtherOpcode == Instr->Description.getOpcode())
       continue;
-    if (!State.getExegesisTarget().checkOpcodeSupported(
+    if (State.getExegesisTarget().checkOpcodeSupported(
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AnastasiyaChernikova wrote:

No, that wasn't correct. We inverted the logic of the default function and the implementation for RISCV, which means we must remove the negation here too

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