Based on my profiling, it seems like the code gen backend (LLVM) is a big offender. A code generator optimized for build times would be nice. (Cranelift seems to be a failure in that regard.)
C++ has an explicit template instantiation feature which helps reduce backend time. I wonder if this can be done in Rust too. Maybe this is what -Zshare-generics=y is for?
I don't know enough C++ or Rust to judge but is it possible that they are optimized around Rust that isn't C++ style? I know I have seen articles about other languages where some very minor changes make a huge difference because the optimizations in place didn't understand what was happening and had to work harder.
And did you try any of the optimization strategies again at 24x? I would be curious if there are differences there.
> I don't know enough C++ or Rust to judge but is it possible that they are optimized around Rust that isn't C++ style? I know I have seen articles about other languages where some very minor changes make a huge difference because the optimizations in place didn't understand what was happening and had to work harder.
Are you talking about run-time optimizations? My article is focused on build times. I don't think what you mentioned applies to build times. I could be wrong, though. (There are certainly compile time traps you can fall into, but I wouldn't know what those are in Rust.)
> And did you try any of the optimization strategies again at 24x? I would be curious if there are differences there.
No, I did not. That's a good suggestion. But I was pretty tired of this project by the time I made the scaling benchmarks. xD
I did actually mean build time. I figured there could be optimizations within the build process which allows some specific style of code to build faster because it has to check things. Perhaps around memory safety, which could be a big deal in the line for line translation.
And I totally understand being tired of it by that point. You did an extremely detailed and well documented process, and it was quite impressive. Thank you for sharing it.
Based on my profiling, it seems like the code gen backend (LLVM) is a big offender. A code generator optimized for build times would be nice. (Cranelift seems to be a failure in that regard.)
C++ has an explicit template instantiation feature which helps reduce backend time. I wonder if this can be done in Rust too. Maybe this is what -Zshare-generics=y is for?