[llvm] [MISched][RISCV] Add anti-dependency breaking to PostMachineScheduler (PR #221984)

[Pengcheng Wang via llvm-commits]

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@@ -826,6 +830,8 @@ void MachineSchedulerBase::scheduleRegions(ScheduleDAGInstrs &Scheduler,
       continue;
 #endif
 
+    Scheduler.startBlock(&*MBB);
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wangpc-pp wrote:

https://github.com/llvm/llvm-project/pull/222270

https://github.com/llvm/llvm-project/pull/221984