[titzer]

Depending on how source programs are split up into files, parsing can be easily parallelized (think one thread per file), while other compilation tasks are harder due to interdependencies. E.g. semantic analysis requires building type representations, global namespaces, etc. Code generation is (usually) parallelizable as well, but there are a couple very serial steps in the middle, too.

My experience is that parsers for source languages can reach into the 1-10mb/s range, and depending on how complex the IRs and transformations are after that, code generation is usually around 0.5mb-5mb/s. The stuff in the middle (dealing with IRs) is harder to measure in terms of bytes.