1 files changed, 8 insertions, 0 deletions
diff --git a/llvm/include/llvm/ADT/STLExtras.h b/llvm/include/llvm/ADT/STLExtras.h
index 274933bc520..430707cbd79 100644
--- a/llvm/include/llvm/ADT/STLExtras.h
+++ b/llvm/include/llvm/ADT/STLExtras.h
@@ -1573,6 +1573,14 @@ template <class Ptr> auto to_address(const Ptr &P) -> decltype(P.operator->()) {
 }
 template <class T> constexpr T *to_address(T *P) { return P; }
 
+template <typename R>
+auto index(R &&TheRange,
+  typename std::iterator_traits<detail::IterOfRange<R>>::difference_type N)
+  -> decltype(TheRange.begin()[N]) {
+  assert(N < TheRange.end() - TheRange.begin() && "Index out of range!");
+  return TheRange.begin()[N];
+}
+
 } // end namespace llvm
 
 #endif // LLVM_ADT_STLEXTRAS_H