From what I know (I used to be software engineer in the hardware design team) Alpha designers used to use domino logic [1]. It allowed for some quite beefy circ

From what I know (I used to be software engineer in the hardware design team) Alpha designers used to use domino logic [1]. It allowed for some quite beefy circuits expressed in smaller space, because domino logic dominantly used nFET transistors which are usually smaller than pFET. Typical k-input Logical AND-NOT uses k pFET and k nFET transistors, the domino logic uses one pFET and k nFET for similar purposes. The paper about domino logic synthesis [2] hints at what Apple uses for their CPU cores. [1] https://en.wikipedia.org/wiki/Domino_logic https://en.wikipedia.org/wiki/Domino_logic [2] https://www.researchgate.net/publication/260714833_1-of-N_Domino_Logic_Synthesis https://www.researchgate.net/publication/260714833_1-of-N_Do...