[llvm] [RemoveDIs][DebugInfo] Verifier and printing fixes for DPLabel (PR #83242)

[Stephen Tozer via llvm-commits]

SLTozer wrote:

> Actually before landing, could you please summarise the testing strategy? It's not clear from the conversation above.

We want to be able to test this patch with `llvm-as`, because that's how we prefer to test verifier changes. However, `llvm-as` won't currently verify any of the test cases in RemoveDI mode because it doesn't support RemoveDIs, but if the test is written in the RemoveDI format then the file will be verifier in RemoveDI mode after parsing; therefore, the testing for this patch is dependent on parser support, which comes afterwards. The two are more-or-less landing alongside each other, so I _think_ it's reasonable to push the tests to a subsequent patch.

https://github.com/llvm/llvm-project/pull/83242