diff --git a/src/arm/v6.rs b/src/arm/v6.rs
index 9d70307536..c74a4110b8 100644
--- a/src/arm/v6.rs
+++ b/src/arm/v6.rs
@@ -19,3 +19,26 @@ pub unsafe fn _rev_u16(x: u16) -> u16 {
 pub unsafe fn _rev_u32(x: u32) -> u32 {
     x.swap_bytes() as u32
 }
+
+#[cfg(test)]
+mod tests {
+    use stdsimd_test::simd_test;
+
+    use arm::v6;
+
+    #[test]
+    fn _rev_u16() {
+        unsafe {
+            assert_eq!(v6::_rev_u16(0b0000_0000_1111_1111_u16), 0b1111_1111_0000_0000_u16);
+        }
+    }
+
+    #[test]
+    fn _rev_u32() {
+        unsafe {
+            assert_eq!(v6::_rev_u32(
+                0b0000_0000_1111_1111_0000_0000_1111_1111_u32
+            ), 0b1111_1111_0000_0000_1111_1111_0000_0000_u32);
+        }
+    }
+}
diff --git a/src/arm/v7.rs b/src/arm/v7.rs
index 1356fe05d2..2ef3cb26b9 100644
--- a/src/arm/v7.rs
+++ b/src/arm/v7.rs
@@ -42,3 +42,40 @@ extern "C" {
     #[link_name="llvm.bitreverse.i32"]
     fn rbit_u32(i: i32) -> i32;
 }
+
+
+#[cfg(test)]
+mod tests {
+    use stdsimd_test::simd_test;
+
+    use arm::v7;
+
+    #[test]
+    fn _clz_u8() {
+        unsafe {
+            assert_eq!(v7::_clz_u8(0b0000_1010u8), 4u8);
+        }
+    }
+
+    #[test]
+    fn _clz_u16() {
+        unsafe {
+            assert_eq!(v7::_clz_u16(0b0000_1010u16), 12u16);
+        }
+    }
+
+    #[test]
+    fn _clz_u32() {
+        unsafe {
+            assert_eq!(v7::_clz_u32(0b0000_1010u32), 28u32);
+        }
+    }
+
+    #[test]
+    fn _rbit_u32() {
+        unsafe {
+            assert_eq!(v7::_rbit_u32(0b0000_1010u32),
+                       0b0101_0000_0000_0000_0000_0000_0000_0000u32);
+        }
+    }
+}
diff --git a/src/arm/v8.rs b/src/arm/v8.rs
index 410edc7deb..b87c34fd75 100644
--- a/src/arm/v8.rs
+++ b/src/arm/v8.rs
@@ -53,3 +53,53 @@ pub unsafe fn _cls_u32(x: u32) -> u32 {
 pub unsafe fn _cls_u64(x: u64) -> u64 {
     u64::leading_zeros(((((((x as i64) >> 63) as u64) ^ x) << 1) | 1)) as u64
 }
+
+#[cfg(test)]
+mod tests {
+    use stdsimd_test::simd_test;
+
+    use arm::v8;
+
+    #[test]
+    fn _rev_u64() {
+        unsafe {
+            assert_eq!(v8::_rev_u64(
+                0b0000_0000_1111_1111_0000_0000_1111_1111_u64
+            ), 0b1111_1111_0000_0000_1111_1111_0000_0000_0000_0000_0000_0000_0000_0000_0000_0000_u64);
+        }
+    }
+
+    #[test]
+    fn _clz_u64() {
+        unsafe {
+            assert_eq!(v8::_clz_u64(0b0000_1010u64), 60u64);
+        }
+    }
+
+    #[test]
+    fn _rbit_u64() {
+        unsafe {
+            assert_eq!(v8::_rbit_u64(
+                0b0000_0000_1111_1101_0000_0000_1111_1111_u64
+            ), 0b1111_1111_0000_0000_1011_1111_0000_0000_0000_0000_0000_0000_0000_0000_0000_0000_u64);
+        }
+    }
+
+    #[test]
+    fn _cls_u32() {
+        unsafe {
+            assert_eq!(v8::_cls_u32(
+                0b1111_1111_1111_1111_0000_0000_1111_1111_u32
+            ), 15_u32);
+        }
+    }
+
+    #[test]
+    fn _cls_u64() {
+        unsafe {
+            assert_eq!(v8::_cls_u64(
+                0b1111_1111_1111_1111_0000_0000_1111_1111_0000_0000_0000_0000_0000_0000_0000_0000_u64
+            ), 15_u64);
+        }
+    }
+}