Hennessy and Patterson on the Roots of RISC

Awarding ACM's 2017 A.M. Turing Award to John Hennessy and David Patterson was richly deserved and long overdue, as described by Neil Savage in his news story "Rewarded for RISC" (June 2018). RISC was a big step forward. In their acceptance speech, Patterson also graciously acknowledged the contemporary and independent invention of the RISC concepts by John Cocke, another Turing laureate, at IBM, as described by Radin.1 Unfortunately, Cocke, who was the principal inventor but rarely published, was not included as an author, and it would have been good if Savage had mentioned his contribution. It is noteworthy that RISC architectures depend on and emerged from optimizing compilers. So far as I can tell, all the RISC inventors had strong backgrounds in both architecture and compilers.