It says right there: "Always look at the source code" fannkuch-redux, n-body, spectral-norm, reverse-complement: the fastest C wins by a large margin because i

It says right there: "Always look at the source code" fannkuch-redux, n-body, spectral-norm, reverse-complement: the fastest C wins by a large margin because it's an unreadable mess of vector intrinsics. If you really wanted to, you can do that in Julia too (and it might read better). Julia looks pretty even with C in the ones that were faithfully translated.