[llvm] [GOFF] Set reference to ADA (PR #179734)

[Kai Nacke via llvm-commits]

redstar wrote:

> @redstar as an aside, I had not realized we have this split where HLASM output for sections is handled in MCAsmInfoGOFF, while HLASM output for symbols is in SystemZHLASMAsmStreamer. That seems unfortunate given the close parallels - we should think about possible refactoring here.

Yes, I have this on my todo list.

https://github.com/llvm/llvm-project/pull/179734