[llvm] [llvm-exegesis] Add AArch64 operand initializers, SetRegTo (PR #169912)

[John Brawn via llvm-commits]

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@@ -224,6 +395,12 @@ Error ExegesisAArch64Target::randomizeTargetMCOperand(
   case llvm::AArch64::OPERAND_IMPLICIT_IMM_0:
     AssignedValue = MCOperand::createImm(0);
     return Error::success();
+  case llvm::AArch64::OPERAND_SHIFTED_REGISTER:
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john-brawn-arm wrote:

It would be better if these operands were randomised (given that this is randomizeTargetMCOperand), though a TODO comment about that would be OK.

https://github.com/llvm/llvm-project/pull/169912