///
/// Behavior is undefined if any of the following conditions are violated:
///
-/// * Both `x` and `y` must be [valid] for reads and writes.
+/// * Both `x` and `y` must be [valid] for both reads and writes.
///
/// * Both `x` and `y` must be properly aligned.
///
///
/// Behavior is undefined if any of the following conditions are violated:
///
-/// * Both `x` and `y` must be [valid] for reads and writes of `count *
+/// * Both `x` and `y` must be [valid] for both reads and writes of `count *
/// size_of::<T>()` bytes.
///
/// * Both `x` and `y` must be properly aligned.