diff --git a/unittests/Support/RegexTest.cpp b/unittests/Support/RegexTest.cpp
new file mode 100644
index 0000000..b323e28
--- /dev/null
+++ b/unittests/Support/RegexTest.cpp
@@ -0,0 +1,64 @@
+//===- llvm/unittest/Support/RegexTest.cpp - Regex tests --===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include "gtest/gtest.h"
+#include "llvm/Support/Regex.h"
+#include <cstring>
+
+using namespace llvm;
+namespace {
+
+class RegexTest : public ::testing::Test {
+};
+
+TEST_F(RegexTest, Basics) {
+  Regex r1("^[0-9]+$");
+  EXPECT_TRUE(r1.match("916"));
+  EXPECT_TRUE(r1.match("9"));
+  EXPECT_FALSE(r1.match("9a"));
+
+  SmallVector<StringRef, 1> Matches;
+  Regex r2("[0-9]+", Regex::Sub);
+  EXPECT_TRUE(r2.match("aa216b", &Matches));
+  EXPECT_EQ(1u, Matches.size());
+  EXPECT_EQ("216", Matches[0].str());
+
+  Regex r3("[0-9]+([a-f])?:([0-9]+)", Regex::Sub);
+  EXPECT_TRUE(r3.match("9a:513b", &Matches));
+  EXPECT_EQ(3u, Matches.size());
+  EXPECT_EQ("9a:513", Matches[0].str());
+  EXPECT_EQ("a", Matches[1].str());
+  EXPECT_EQ("513", Matches[2].str());
+
+  EXPECT_TRUE(r3.match("9:513b", &Matches));
+  EXPECT_EQ(3u, Matches.size());
+  EXPECT_EQ("9:513", Matches[0].str());
+  EXPECT_EQ("", Matches[1].str());
+  EXPECT_EQ("513", Matches[2].str());
+
+  Regex r4("a[^b]+b", Regex::Sub);
+  std::string String="axxb";
+  String[2] = '\0';
+  EXPECT_FALSE(r4.match("abb"));
+  EXPECT_TRUE(r4.match(String, &Matches));
+  EXPECT_EQ(1u, Matches.size());
+  EXPECT_EQ(String, Matches[0].str());
+
+
+  std::string NulPattern="X[0-9]+X([a-f])?:([0-9]+)";
+  String="YX99a:513b";
+  NulPattern[7] = '\0';
+  Regex r5(NulPattern, Regex::Sub);
+  EXPECT_FALSE(r5.match(String));
+  EXPECT_FALSE(r5.match("X9"));
+  String[3]='\0';
+  EXPECT_TRUE(r5.match(String));
+}
+
+}