[llvm] [llvm-exegesis] Add HasNoSchedulingInfo flag to MCInstDesc. (PR #143840)

[Jason Eckhardt via llvm-commits]

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@@ -430,6 +431,11 @@ class MCInstrDesc {
     return Flags & (1ULL << MCID::Authenticated);
   }
 
+  /// Return true if this instruction has no scheduling info.
+  bool hasNoSchedulingInfo() const {
+    return Flags & (1ULL << MCID::HasNoSchedulingInfo);
+  }
+
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nvjle wrote:

Does the existing `MCInstrDesc::getSchedClass() == 0` have the same effect? 

https://github.com/llvm/llvm-project/pull/143840