[llvm] [MachineScheduler][AMDGPU] Allow scheduling of single-MI regions (PR #128739)

[Matt Arsenault via llvm-commits]

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@@ -124,6 +124,9 @@ namespace llvm {
     /// rescheduling).
     bool RemoveKillFlags;
 
+    /// True if regions with a single MI should be scheduled.
+    bool ScheduleSingleMIRegions = false;
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arsenm wrote:

Over-configuration? Can you just unconditionally do this? 

https://github.com/llvm/llvm-project/pull/128739