[llvm] [MachineScheduler] Experimental option to partially disable pre-ra scheduling. (PR #90181)

[Jonas Paulsson via llvm-commits]

JonPsson1 wrote:

I don't think this branch will actually land, although there may be some ideas worth trying. I have now another PR in progress that will replace this one. See #135076.

@michaelmaitland Maybe you would like to try the new SystemZPreRASchedStrategy and see if it works on your target as well?

https://github.com/llvm/llvm-project/pull/90181