--- /dev/null
+++ libmalloc/libmalloc-166.220.1/tests/MallocBench/churn.cpp
@@ -0,0 +1,53 @@
+/*
+ * Copyright (C) 2014 Apple Inc. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE INC. OR
+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
+ * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 
+ */
+
+#include "CPUCount.h"
+#include "churn.h"
+#include <memory>
+#include <stddef.h>
+
+#include "mbmalloc.h"
+
+struct HeapDouble {
+    void* operator new(size_t size) { return mbmalloc(size); }
+    void operator delete(void* p, size_t size) { mbfree(p, size); }
+
+    HeapDouble(double d) : value(d) { }
+    const HeapDouble& operator+=(const HeapDouble& other) { value += other.value; return *this; }
+    double value;
+};
+
+void benchmark_churn(bool isParallel)
+{
+    size_t times = 7000000;
+    if (isParallel)
+        times /= cpuCount();
+
+    auto total = std::unique_ptr<HeapDouble>(new HeapDouble(0.0));
+    for (size_t i = 0; i < times; ++i) {
+        auto heapDouble = std::unique_ptr<HeapDouble>(new HeapDouble(i));
+        *total += *heapDouble;
+    }
+}