[llvm] [StackSlotColoring] Ignore non-spill objects in RemoveDeadStores. (PR #80242)

[Philip Reames via llvm-commits]

preames wrote:

> also don't really want to leave isLoadFromStackSlot in its current state because it's sort of a trap.

Agreed.  There's also some other cleanup here would be good - like migrating the interface to Register.  I'm just arguing for fixing the known bug before we worry about the foot-gun in general.  :)

> What restriction are you talking about? 

I'd specifically meant isSpillSlotObjectIndex, sorry if that was not clear.  I'd meant "restriction on which type of FI", not "restriction to being an FI".  

https://github.com/llvm/llvm-project/pull/80242