Funnily, one of the comments on the answer did reference Chen's ONT: > I see your NOP (90h), and raise you an explicit DS prefix (3Eh). It's all about the styl

Funnily, one of the comments on the answer did reference Chen's ONT: > I see your NOP (90h), and raise you an explicit DS prefix (3Eh). It's all about the style points! :-) Any instruction with a memory operand can have a segment prefix. In this case, the DS prefix is implicit/implied, but it can be explicitly specified without changing the meaning of the instruction. Both ways work to pad the extra leftover byte of space, but the explicit DS prefix does not change the instruction's execution speed, whereas the NOP actually takes 1 cycle of time to execute (plus possible decoding). – Cody Gray Style points is linked to https://devblogs.microsoft.com/oldnewthing/20121113-00/?p=6103 https://devblogs.microsoft.com/oldnewthing/20121113-00/?p=61... which is about a bug in Microsoft Money (a useful product that was killed by the Windows 8 MSN).