[llvm] [CodeGen] Introduce MI flag for Live Range split instructions (PR #117543)

[Quentin Colombet via llvm-commits]

qcolombet wrote:

> > Why do you need this information?
> > At the end of the day this is just a regular copy.
> 
> Can you see the other PR in the stack? #117544 It is indeed just another copy. That's the real problem when identifying the LR split instructions from the other COPY instructions. 

My point is why do you have to distinguish them to begin with?
Can't you apply your "push down" transformation on all the COPYs that you can?

https://github.com/llvm/llvm-project/pull/117543