[llvm] [LiveDebugVariables] Add basic verification (PR #79846)

[Jay Foad via llvm-commits]

jayfoad wrote:

> > > Can you disable the verifier in those tests for now?
> > 
> > 
> > That seems dangerous - these are real bugs so they could show up in compiling real code, not just in tests.
> 
> Yes, but the current state is we have no verification so new bugs will appear.

I don't think there's a generic way to disable verification of analyses. Are you suggesting adding a new `-verify-live-debug-variables` option that I can set to 0 in the failing tests, and users can set to 0 if their compilation crashes (if they were using an Asserts build of the compiler)?

https://github.com/llvm/llvm-project/pull/79846