ADT: Move ArrayRef comparison operators into the class

Summary:
This allows the implicit ArrayRef conversions to kick in when e.g.
comparing ArrayRef to a SmallVector.

Reviewers: zturner, dblaikie

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D48632

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@335839 91177308-0d34-0410-b5e6-96231b3b80d8

include/llvm/ADT/ArrayRef.h

@@ -272,6 +272,16 @@ namespace llvm {
       return std::vector<T>(Data, Data+Length);
     }
 
+    /// @}
+    /// @name Comparison operators
+    /// @{
+
+    friend bool operator==(ArrayRef LHS, ArrayRef RHS) {
+      return LHS.equals(RHS);
+    }
+
+    friend bool operator!=(ArrayRef LHS, ArrayRef RHS) { return !(LHS == RHS); }
+
     /// @}
   };
 
@@ -510,22 +520,6 @@ namespace llvm {
     return MutableArrayRef<T>(data, length);
   }
 
-  /// @}
-  /// @name ArrayRef Comparison Operators
-  /// @{
-
-  template<typename T>
-  inline bool operator==(ArrayRef<T> LHS, ArrayRef<T> RHS) {
-    return LHS.equals(RHS);
-  }
-
-  template<typename T>
-  inline bool operator!=(ArrayRef<T> LHS, ArrayRef<T> RHS) {
-    return !(LHS == RHS);
-  }
-
-  /// @}
-
   // ArrayRefs can be treated like a POD type.
   template <typename T> struct isPodLike;
   template <typename T> struct isPodLike<ArrayRef<T>> {

unittests/ADT/ArrayRefTest.cpp

@@ -188,6 +188,10 @@ TEST(ArrayRefTest, Equals) {
   EXPECT_TRUE(AR1b.equals({3, 4, 5, 6}));
   EXPECT_FALSE(AR1b.equals({2, 3, 4, 5, 6}));
   EXPECT_FALSE(AR1b.equals({3, 4, 5, 6, 7}));
+
+  SmallVector<int, 8> V1{1, 2, 3, 4, 5, 6, 7, 8};
+  EXPECT_EQ(AR1, V1);
+  EXPECT_EQ(V1, AR1);
 }
 
 TEST(ArrayRefTest, EmptyEquals) {