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

[Jeffrey Byrnes via llvm-commits]

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@@ -69,6 +69,14 @@ static cl::opt<bool>
 static cl::opt<bool> UseTBAA("use-tbaa-in-sched-mi", cl::Hidden,
     cl::init(true), cl::desc("Enable use of TBAA during MI DAG construction"));
 
+static cl::opt<bool>
+    EnableSchedModel("schedmodel", cl::Hidden, cl::init(true),
+                     cl::desc("Use TargetSchedModel for latency lookup"));
+
+static cl::opt<bool>
+    EnableSchedItins("scheditins", cl::Hidden, cl::init(true),
+                     cl::desc("Use InstrItineraryData for latency lookup"));
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jrbyrnes wrote:

As far as I can tell -- I don't see this mutual exclusion constraint encoded. It seems like the API handles the case of having neither --

Default if both are missing --
https://github.com/llvm/llvm-project/blob/173ec728d287f989053bd77521b3497b069c98a2/llvm/lib/CodeGen/TargetSchedule.cpp#L179

Default if both are missing --
https://github.com/llvm/llvm-project/blob/173ec728d287f989053bd77521b3497b069c98a2/llvm/lib/CodeGen/TargetSchedule.cpp#L269


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