1 files changed, 49 insertions, 0 deletions
diff --git a/library/stdarch/crates/core_arch/src/arm/v6.rs b/library/stdarch/crates/core_arch/src/arm/v6.rs
new file mode 100644
index 000000000..5df30cd62
--- /dev/null
+++ b/library/stdarch/crates/core_arch/src/arm/v6.rs
@@ -0,0 +1,49 @@
+//! ARMv6 intrinsics.
+//!
+//! The reference is [ARMv6-M Architecture Reference Manual][armv6m].
+//!
+//! [armv6m]:
+//! http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.ddi0419c/index.
+//! html
+
+#[cfg(test)]
+use stdarch_test::assert_instr;
+
+/// Reverse the order of the bytes.
+#[inline]
+#[cfg_attr(test, assert_instr(rev))]
+pub unsafe fn _rev_u16(x: u16) -> u16 {
+    x.swap_bytes() as u16
+}
+
+/// Reverse the order of the bytes.
+#[inline]
+#[cfg_attr(test, assert_instr(rev))]
+pub unsafe fn _rev_u32(x: u32) -> u32 {
+    x.swap_bytes() as u32
+}
+
+#[cfg(test)]
+mod tests {
+    use crate::core_arch::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
+            );
+        }
+    }
+}