[llvm] [ScheduleDAG] Allow disabling the SchedModel / Itineraries during Scheduling (PR #138057)

[Matt Arsenault via llvm-commits]

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@@ -40,19 +40,23 @@ static cl::opt<bool> ForceEnableIntervals(
     cl::desc("Force the use of resource intervals in the schedule model"));
 
 bool TargetSchedModel::hasInstrSchedModel() const {
-  return EnableSchedModel && SchedModel.hasInstrSchedModel();
+  return EnableSchedModel && SchedModel.hasInstrSchedModel() &&
+         !DisableItinerariesAndSchedModel;
 }
 
 bool TargetSchedModel::hasInstrItineraries() const {
-  return EnableSchedItins && !InstrItins.isEmpty();
+  return EnableSchedItins && !InstrItins.isEmpty() &&
+         !DisableItinerariesAndSchedModel;
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arsenm wrote:

I don't see how this isn't equivalent to just using -scheditins=0

https://github.com/llvm/llvm-project/pull/138057