[llvm] [MISched] Extend overridePostRASchedPolicy to support per-function scheduling direction (PR #149297)

[Pengcheng Wang via llvm-commits]

wangpc-pp wrote:

I still think we should pass `SchedRegion`. The signature will be:
```
void overridePostRASchedPolicy(MachineSchedPolicy &Policy,
                               const SchedRegion &Region) const
```
The parameters are less and it is more straightforward since the scheduler is region-based, `MachineBasicBlock` != `SchedRegion` conceptively.

https://github.com/llvm/llvm-project/pull/149297