There’s No Such Thing as a General-purpose Processor

There is an increasing trend in computer architecture to categorize processors and accelerators as "general purpose." Of the papers published at this year’s International Symposium on Computer Architecture (ISCA 2014), nine out of 45 explicitly referred to general-purpose processors; one additionally referred to general-purpose FPGAs (field-programmable gate arrays), and another referred to general-purpose MIMD (multiple instruction, multiple data) supercomputers, stretching the definition to the breaking point. This article presents the argument that there is no such thing as a truly general-purpose processor and that the belief in such a device is harmful.