Hardware–Software Co-Design: Not Just a Cliché

The age of the air-tight hardware abstraction is over. As the computing ecosystem moves beyond the predictable yearly advances of Moore’s Law, appeals to familiarity and backwards compat-ibility will become less convincing: fundamental shifts in abstraction and design will look more enticing. It is time to embrace hardware–software co-design in earnest, to cooperate between pro-gramming languages and architecture to upend legacy constraints on computing. We describe our work on approximate computing, a new avenue spanning the system stack from applications and languages to microarchitectures. We reflect on the challenges and successes of approxima-tion research and, with these lessons in mind, distill opportunities for future hardware–software co-design efforts