diff --git a/test/unit/test_leb128.cpp b/test/unit/test_leb128.cpp
new file mode 100644
index 0000000000..95def52528
--- /dev/null
+++ b/test/unit/test_leb128.cpp
@@ -0,0 +1,105 @@
+//===- llvm/unittest/Support/LEB128Test.cpp - LEB128 function tests -------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include "leb128.h"
+
+#include "gtest/gtest.h"
+
+#include <string>
+
+#include "llvm/StringRef.h"
+
+#include "raw_istream.h"
+
+namespace ntimpl {
+
+TEST(LEB128Test, WriteULEB128) {
+#define EXPECT_ULEB128_EQ(EXPECTED, VALUE, PAD) \
+  do { \
+    llvm::StringRef expected(EXPECTED, sizeof(EXPECTED)-1); \
+    char buf[32]; \
+    std::size_t size = WriteUleb128(buf, VALUE); \
+    llvm::StringRef actual(buf, size); \
+    EXPECT_EQ(expected, actual); \
+  } while (0)
+
+  // Write ULEB128
+  EXPECT_ULEB128_EQ("\x00", 0, 0);
+  EXPECT_ULEB128_EQ("\x01", 1, 0);
+  EXPECT_ULEB128_EQ("\x3f", 63, 0);
+  EXPECT_ULEB128_EQ("\x40", 64, 0);
+  EXPECT_ULEB128_EQ("\x7f", 0x7f, 0);
+  EXPECT_ULEB128_EQ("\x80\x01", 0x80, 0);
+  EXPECT_ULEB128_EQ("\x81\x01", 0x81, 0);
+  EXPECT_ULEB128_EQ("\x90\x01", 0x90, 0);
+  EXPECT_ULEB128_EQ("\xff\x01", 0xff, 0);
+  EXPECT_ULEB128_EQ("\x80\x02", 0x100, 0);
+  EXPECT_ULEB128_EQ("\x81\x02", 0x101, 0);
+
+#undef EXPECT_ULEB128_EQ
+}
+
+TEST(LEB128Test, ReadUleb128) {
+#define EXPECT_READ_ULEB128_EQ(EXPECTED, VALUE) \
+  do { \
+    unsigned long val = 0; \
+    std::size_t size = ReadUleb128(VALUE, &val); \
+    EXPECT_EQ(sizeof(VALUE) - 1, size); \
+    EXPECT_EQ(EXPECTED, val); \
+  } while (0)
+
+  // Read ULEB128
+  EXPECT_READ_ULEB128_EQ(0u, "\x00");
+  EXPECT_READ_ULEB128_EQ(1u, "\x01");
+  EXPECT_READ_ULEB128_EQ(63u, "\x3f");
+  EXPECT_READ_ULEB128_EQ(64u, "\x40");
+  EXPECT_READ_ULEB128_EQ(0x7fu, "\x7f");
+  EXPECT_READ_ULEB128_EQ(0x80u, "\x80\x01");
+  EXPECT_READ_ULEB128_EQ(0x81u, "\x81\x01");
+  EXPECT_READ_ULEB128_EQ(0x90u, "\x90\x01");
+  EXPECT_READ_ULEB128_EQ(0xffu, "\xff\x01");
+  EXPECT_READ_ULEB128_EQ(0x100u, "\x80\x02");
+  EXPECT_READ_ULEB128_EQ(0x101u, "\x81\x02");
+  EXPECT_READ_ULEB128_EQ(8320u, "\x80\xc1\x80\x80\x10");
+
+#undef EXPECT_READ_ULEB128_EQ
+}
+
+TEST(LEB128Test, SizeUleb128) {
+  // Testing Plan:
+  // (1) 128 ^ n ............ need (n+1) bytes
+  // (2) 128 ^ n * 64 ....... need (n+1) bytes
+  // (3) 128 ^ (n+1) - 1 .... need (n+1) bytes
+
+  EXPECT_EQ(1u, SizeUleb128(0)); // special case
+
+  EXPECT_EQ(1u, SizeUleb128(0x1UL));
+  EXPECT_EQ(1u, SizeUleb128(0x40UL));
+  EXPECT_EQ(1u, SizeUleb128(0x7fUL));
+
+  EXPECT_EQ(2u, SizeUleb128(0x80UL));
+  EXPECT_EQ(2u, SizeUleb128(0x2000UL));
+  EXPECT_EQ(2u, SizeUleb128(0x3fffUL));
+
+  EXPECT_EQ(3u, SizeUleb128(0x4000UL));
+  EXPECT_EQ(3u, SizeUleb128(0x100000UL));
+  EXPECT_EQ(3u, SizeUleb128(0x1fffffUL));
+
+  EXPECT_EQ(4u, SizeUleb128(0x200000UL));
+  EXPECT_EQ(4u, SizeUleb128(0x8000000UL));
+  EXPECT_EQ(4u, SizeUleb128(0xfffffffUL));
+
+  EXPECT_EQ(5u, SizeUleb128(0x10000000UL));
+  EXPECT_EQ(5u, SizeUleb128(0x400000000UL));
+  EXPECT_EQ(5u, SizeUleb128(0x7ffffffffUL));
+
+  EXPECT_EQ(5u, SizeUleb128(UINT32_MAX));
+}
+
+}  // namespace ntimpl