[llvm] [RemoveDIs] Update Coroutine passes to handle DPValues (PR #74480)

[Orlando Cazalet-Hyams via llvm-commits]

OCHyams wrote:

Thanks @felipepiovezan for the review.

> Where can I read more about it?

@jmorse posted some links above. To briefly contextualise the classes used here, we have `DPMarkers` attached to some instructions which each own a list of `DPValue`s. `DPValue`s are the dbg intrinsic replacement and they get moved (or not) when instructions are moved based on extra information passed to the `moveBefore`/`moveAfter` functions. Instruction iterators now carry extra bits to indicate whether or not it conceptually points before the `DPValue`s. That's why we need to update `getInsertPtAfterFramePtr`.

> I find it surprising that there were no test changes

We're aiming for identical output with/without the new debug info mode - the no-debug-instruction mode should be a drop-in replacement for debug-intrinsic mode.

https://github.com/llvm/llvm-project/pull/74480