[llvm-branch-commits] [llvm] [KeyInstr][DwarfDebug] Add is_stmt emission support (PR #133495)

[Jeremy Morse via llvm-branch-commits]

https://github.com/jmorse commented:

I get the impression that `GroupCandidates` and `KeyInstructions` are being kept strictly in sync; thus couldn't one instead just load KeyInstructions from GroupCandidates once the scan is complete? This avoids filling up the dense map with tombstones.

Am I right in understanding that the buoy means the "least precedence" instruction will get the is_stmt if the highest precedence appears after it in the contiguous blob? (Seems fine, just making sure I understand).

On the whole, the computation function feels like it could be simpler, but in some intangible way I'm not immediately sure of. (Still reading the tests).

https://github.com/llvm/llvm-project/pull/133495