Everyone has CLZ.

Even armv5 had CLZ.

Change-Id: I51bc8d1166d09940fd0d3f4c7717edf26977082c
diff --git a/tests/strings_test.cpp b/tests/strings_test.cpp
new file mode 100644
index 0000000..5200859
--- /dev/null
+++ b/tests/strings_test.cpp
@@ -0,0 +1,32 @@
+/*
+ * Copyright (C) 2013 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <gtest/gtest.h>
+
+#include <errno.h>
+#include <strings.h>
+
+TEST(strings, ffs) {
+  ASSERT_EQ( 0, ffs(0x00000000));
+  ASSERT_EQ( 1, ffs(0x00000001));
+  ASSERT_EQ( 6, ffs(0x00000020));
+  ASSERT_EQ(11, ffs(0x00000400));
+  ASSERT_EQ(16, ffs(0x00008000));
+  ASSERT_EQ(17, ffs(0x00010000));
+  ASSERT_EQ(22, ffs(0x00200000));
+  ASSERT_EQ(27, ffs(0x04000000));
+  ASSERT_EQ(32, ffs(0x80000000));
+}