diff --git a/llvm/include/llvm/IR/DerivedTypes.h b/llvm/include/llvm/IR/DerivedTypes.h
--- a/llvm/include/llvm/IR/DerivedTypes.h
+++ b/llvm/include/llvm/IR/DerivedTypes.h
@@ -531,18 +531,6 @@
   }
 };
 
-unsigned Type::getVectorNumElements() const {
-  return cast<VectorType>(this)->getNumElements();
-}
-
-bool Type::getVectorIsScalable() const {
-  return cast<VectorType>(this)->isScalable();
-}
-
-ElementCount Type::getVectorElementCount() const {
-  return cast<VectorType>(this)->getElementCount();
-}
-
 bool Type::isVectorTy() const { return isa<VectorType>(this); }
 
 /// Class to represent pointers.
@@ -597,8 +585,8 @@
       isIntOrIntVectorTy() &&
       "Original type expected to be a vector of integers or a scalar integer.");
   Type *NewType = getIntNTy(getContext(), NewBitWidth);
-  if (isVectorTy())
-    NewType = VectorType::get(NewType, getVectorElementCount());
+  if (auto *VTy = dyn_cast<VectorType>(this))
+    NewType = VectorType::get(NewType, VTy->getElementCount());
   return NewType;
 }
 
@@ -606,6 +594,12 @@
   return cast<PointerType>(getScalarType())->getAddressSpace();
 }
 
+Type *Type::getScalarType() const {
+  if (isVectorTy())
+    return cast<VectorType>(this)->getElementType();
+  return const_cast<Type *>(this);
+}
+
 } // end namespace llvm
 
 #endif // LLVM_IR_DERIVEDTYPES_H
diff --git a/llvm/include/llvm/IR/Type.h b/llvm/include/llvm/IR/Type.h
--- a/llvm/include/llvm/IR/Type.h
+++ b/llvm/include/llvm/IR/Type.h
@@ -300,11 +300,7 @@
 
   /// If this is a vector type, return the element type, otherwise return
   /// 'this'.
-  Type *getScalarType() const {
-    if (isVectorTy())
-      return getVectorElementType();
-    return const_cast<Type*>(this);
-  }
+  inline Type *getScalarType() const;
 
   //===--------------------------------------------------------------------===//
   // Type Iteration support.
@@ -339,8 +335,8 @@
 
   //===--------------------------------------------------------------------===//
   // Helper methods corresponding to subclass methods.  This forces a cast to
-  // the specified subclass and calls its accessor.  "getVectorNumElements" (for
-  // example) is shorthand for cast<VectorType>(Ty)->getNumElements().  This is
+  // the specified subclass and calls its accessor.  "getArrayNumElements" (for
+  // example) is shorthand for cast<ArrayType>(Ty)->getNumElements().  This is
   // only intended to cover the core methods that are frequently used, helper
   // methods should not be added here.
 
@@ -361,14 +357,6 @@
     return ContainedTys[0];
   }
 
-  inline bool getVectorIsScalable() const;
-  inline unsigned getVectorNumElements() const;
-  inline ElementCount getVectorElementCount() const;
-  Type *getVectorElementType() const {
-    assert(getTypeID() == VectorTyID);
-    return ContainedTys[0];
-  }
-
   Type *getPointerElementType() const {
     assert(getTypeID() == PointerTyID);
     return ContainedTys[0];