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Since it is a 2-year old thread and Bailangshan did not provide much about the context of "Annals of the supreme ancestor", I am not quite sure about whether it mean the Art of War or not.
However, in the context of
SGZ or 3K period, "supreme ancestor" (taizu 太祖) should mean Cao Cao. In the context of traditional Chinese historiography, the word "annal" (ji 紀) is often associated with the chronological style of the emperors' biographies, including Cao Cao's. Hence there is a high chance that Bailangshan was referring to Cao Cao's biography in SGZ, despite its formal name being the Annal of Emperor Wu (Martial Emperor). Quite a few Chinese historians have actually misquoted it as so.
On the other hand, there is nothing about the Art of War that can be considered "annalistic", and its English text is just too easily available. The historical Cao Cao has written commentaries to the Art of War but never compiled a whole new book as portrayed in Luo's novel. The story about Zhang Song reciting Cao Cao's work did not happen in history, and Cao Cao's commentaries also existed at least until the Tang Dynasty.
But then again, without more information from Bailangshan, it would be impossible to get a definite answer.