Merge to upstream r225300.

Change-Id: I2b23715db9ac129ff80aa78ad5824db0a4d6fbb3

test/std/numerics/numeric.ops/accumulate/accumulate_op.pass.cpp

@@ -0,0 +1,55 @@
+//===----------------------------------------------------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is dual licensed under the MIT and the University of Illinois Open
+// Source Licenses. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+// <numeric>
+
+// template <InputIterator Iter, MoveConstructible T,
+//           Callable<auto, const T&, Iter::reference> BinaryOperation>
+//   requires HasAssign<T, BinaryOperation::result_type>
+//         && CopyConstructible<BinaryOperation>
+//   T
+//   accumulate(Iter first, Iter last, T init, BinaryOperation binary_op);
+
+#include <numeric>
+#include <functional>
+#include <cassert>
+
+#include "test_iterators.h"
+
+template <class Iter, class T>
+void
+test(Iter first, Iter last, T init, T x)
+{
+    assert(std::accumulate(first, last, init, std::multiplies<T>()) == x);
+}
+
+template <class Iter>
+void
+test()
+{
+    int ia[] = {1, 2, 3, 4, 5, 6};
+    unsigned sa = sizeof(ia) / sizeof(ia[0]);
+    test(Iter(ia), Iter(ia), 1, 1);
+    test(Iter(ia), Iter(ia), 10, 10);
+    test(Iter(ia), Iter(ia+1), 1, 1);
+    test(Iter(ia), Iter(ia+1), 10, 10);
+    test(Iter(ia), Iter(ia+2), 1, 2);
+    test(Iter(ia), Iter(ia+2), 10, 20);
+    test(Iter(ia), Iter(ia+sa), 1, 720);
+    test(Iter(ia), Iter(ia+sa), 10, 7200);
+}
+
+int main()
+{
+    test<input_iterator<const int*> >();
+    test<forward_iterator<const int*> >();
+    test<bidirectional_iterator<const int*> >();
+    test<random_access_iterator<const int*> >();
+    test<const int*>();
+}