[viktorcode]

I'm wondering what you needed to write unsafe code for? Could there be another way to get rid of reference counting for your use case?

Another question, have you tried using Accelerate framework to solve performance bottlenecks (or save yourself from having to write your own calc code)?

[avitzur]

Most of the performance critical sections are numeric computation loops. I use the Unsafe APIs where profiling shows that the bounds-checking overhead is significant.

In principle, I could get rid of reference counting overhead by using value types or immutable data. I couldn't see a simple path to doing that without re-architecting everything (with no guarantee that the end result would not just have different performance issues.) For the moment, I'm awaiting compiler improvements before re-evaluating the tradeoffs. There is certainly room for the compiler to reason better on eliding retain/release. https://github.com/apple/swift/issues/58549

Yes, the code does use Accelerate where applicable. That is one component of the numeric evaluation. It addresses the lowest level of things like evaluate the sin function on every array element, or multiply there arrays element wise. Performance tuning is a game of whack-a-mole. There's always another bottleneck somewhere.