[llvm] [llvm-exegesis][AArch64] Disable pauth and ldgm as unsupported instructions (PR #132346)

[via llvm-commits]

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@@ -335,6 +335,9 @@ class ExegesisTarget {
   const OpcodeAvailabilityChecker IsOpcodeAvailable;
 };
 
+bool isPointerAuth(unsigned Opcode);
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lakshayk-nv wrote:

Yes, That implementation was bad. 
Updated implementation, Now overriding getIgnoredOpcodeReasonOrNull() , which checks isPointerAuth() and isLoadTagMultiple() additionally for AArch64.

Thanks :)

https://github.com/llvm/llvm-project/pull/132346