[llvm] TableGen support for RegisterBankInfo (PR #71357)

[via llvm-commits]

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@@ -289,6 +299,141 @@ void RegisterBankEmitter::emitBaseClassImplementation(
      << "} // end namespace llvm\n";
 }
 
+// TableGen already had some RegisterBankInfo support:
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CBSears wrote:

Yeah, that was mostly for me. I'll simplify it.

https://github.com/llvm/llvm-project/pull/71357