[NFC] Remove unnecessary cast.

[antonio-cortes-perez]

Summary

I was reading this post:
https://www.fluentcpp.com/2017/05/19/crtp-helper/

And I noticed that most likely this cast is not needed.
Unless it is needed by some compiler versions.
I tested it with:
cmake --build . --target check-mlir

[antonio-cortes-perez]

Friendly ping. I would appreciate if anyone could help reviewing this small NFC.

[rriddle]

Looks good.

(I was OOO, sorry for the delay)

mlir/include/mlir/IR/OpDefinition.h

324–326

We could probably just do:

[antonio-cortes-perez]

[NFC] Remove unnecessary casts.

+ Applied suggestion of removing additional cast.
+ Removed comment that no longer applies.

[antonio-cortes-perez]

mlir/include/mlir/IR/OpDefinition.h

324–326

Nice! Thanks for the suggestion. I also removed the comment which no longer applies. Could you please help me to commit it?

mlir/include/mlir/IR/OpDefinition.h

 } // namespace impl
 
 /// Helper class for implementing traits.  Clients are not expected to interact
 /// with this directly, so its members are all protected.
 template <typename ConcreteType, template <typename> class TraitType>
 class TraitBase {
 protected:
   /// Return the ultimate Operation being worked on.
   Operation *getOperation() {
-    // We have to cast up to the trait type, then to the concrete type, then to
-    // the BaseState class in explicit hops because the concrete type will
-    // multiply derive from the (content free) TraitBase class, and we need to
-    // be able to disambiguate the path for the C++ compiler.
-    auto *trait = static_cast<TraitType<ConcreteType> *>(this);
-    auto *concrete = static_cast<ConcreteType *>(trait);
-    auto *base = static_cast<OpState *>(concrete);
-    return base->getOperation();
+    auto *concrete = static_cast<ConcreteType *>(this);
+    return concrete->getOperation();
   }
 };
 
 //===----------------------------------------------------------------------===//
 // Operand Traits
 
 namespace detail {
 /// Utility trait base that provides accessors for derived traits that have