[llvm] [MISched](NFC) Factor control dependency construction state and logic out of `buildSchedGraph` (PR #226533)

[Alexis Engelke via llvm-commits]

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@@ -42,6 +42,7 @@
 
 #include "llvm/ADT/STLExtras.h"
 #include "llvm/ADT/SetVector.h"
+#include "llvm/Analysis/AliasAnalysis.h"
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aengelke wrote:

Ah, my bad, sorry. I think what caused the regression is that the LLVM-CodeGen PCH includes MachineScheduler.h -> ScheduleDAGInstrs.h and therefore no longer includes AliasAnalysis.h. Not fully sure about what to do here, though. But it feels like this regression is avoidable.

https://github.com/llvm/llvm-project/pull/226533