--- /dev/null	2018-04-03 12:55:20.301839954 +0200
+++ new/test/hotspot/gtest/gc/z/test_zVirtualMemory.cpp	2018-06-08 19:47:02.921574349 +0200
@@ -0,0 +1,30 @@
+/*
+ * Copyright (c) 2016, Oracle and/or its affiliates. All rights reserved.
+ * ORACLE PROPRIETARY/CONFIDENTIAL.  Use is subject to license terms.
+ */
+
+#include "precompiled.hpp"
+#include "gc/z/zVirtualMemory.inline.hpp"
+#include "utilities/debug.hpp"
+#include "unittest.hpp"
+
+TEST(ZVirtualMemory, split) {
+  const size_t PageSize = 2 * M;
+
+  ZVirtualMemory mem(0, 10 * PageSize);
+
+  ZVirtualMemory mem_split0 = mem.split(0 * PageSize);
+  EXPECT_EQ(mem_split0.size(),  0 * PageSize);
+  EXPECT_EQ(       mem.size(), 10 * PageSize);
+
+  ZVirtualMemory mem_split1 = mem.split(5u * PageSize);
+  EXPECT_EQ(mem_split1.size(),  5 * PageSize);
+  EXPECT_EQ(       mem.size(),  5 * PageSize);
+
+  ZVirtualMemory mem_split2 = mem.split(5u * PageSize);
+  EXPECT_EQ(mem_split2.size(),  5 * PageSize);
+  EXPECT_EQ(       mem.size(),  0 * PageSize);
+
+  ZVirtualMemory mem_split3 = mem.split(0 * PageSize);
+  EXPECT_EQ(mem_split3.size(),  0 * PageSize);
+}