[CakeML-dev] Compilation times

[Scott Owens]

We now we have a preliminary version of the bootstrapped compiler that can actually run, and the compile times are pretty bad. It takes almost 2 minutes to compile fib. However, I don’t think that the problem is that the bootstrap is generating bad code for the compiler, or that we haven’t done enough optimisations yet. All of the other benchmark programs give us decent results, within a factor 3 or so of OCaml in the worst case (and sometimes faster than OCaml).

I think this tells us that we have an algorithmic complexity problem in the compiler somewhere. If this is the case, then fixing it should speed up the bootstrap too, so I would like to put a high priority on fixing this. The bootstrap seems to spend most of its time in the assembler-level and later phases of compilation, so I guess this is the place to start looking. Are there any places where we already know it is using a quadratic (or worse) algorithm?

Scott