Remove unreachable code in ArrayIntersectExcept (#10712)

Summary: Pull Request resolved: #10712

Reviewed By: kagamiori

Differential Revision: D61109228

Pulled By: kewang1024

fbshipit-source-id: b417c537aa04aba4b4383e9d2e6bf7db8c9fcdb5

velox/functions/prestosql/ArrayIntersectExcept.cpp

@@ -43,10 +43,10 @@ struct SetWithNull {
 // Generates a set based on the elements of an ArrayVector. Note that we take
 // rightSet as a parameter (instead of returning a new one) to reuse the
 // allocated memory.
-template <typename T, typename TVector>
+template <typename T>
 void generateSet(
     const ArrayVector* arrayVector,
-    const TVector* arrayElements,
+    const DecodedVector* arrayElements,
     vector_size_t idx,
     SetWithNull<T>& rightSet) {
   auto size = arrayVector->sizeAt(idx);
@@ -57,13 +57,7 @@ void generateSet(
     if (arrayElements->isNullAt(i)) {
       rightSet.hasNull = true;
     } else {
-      // Function can be called with either FlatVector or DecodedVector, but
-      // their APIs are slightly different.
-      if constexpr (std::is_same_v<TVector, DecodedVector>) {
-        rightSet.set.insert(arrayElements->template valueAt<T>(i));
-      } else {
-        rightSet.set.insert(arrayElements->valueAt(i));
-      }
+      rightSet.set.insert(arrayElements->template valueAt<T>(i));
     }
   }
 }