[llvm] [DWARF] Emit a worst-case prologue_end flag for pathological inputs (PR #107849)

[Orlando Cazalet-Hyams via llvm-commits]

https://github.com/OCHyams commented:

Looking at the code, I've left some nits and one more meaningful question.

Behaviourally, this SGTM, but I think it would be great if the proposed behaviour also got a quick look from an LLDB-person (@prantl / @JDevlieghere ) and/or @dwblaikie, as I could imagine debuggers having special-casing for idiosyncratic compiler output for this kind of thing.

https://github.com/llvm/llvm-project/pull/107849