See https://github.com/JuliaLang/julia/pull/5227 https://github.com/JuliaLang/julia/pull/5227 for the open PR. The benchmark there suggests 2-3x improvement. Th

See https://github.com/JuliaLang/julia/pull/5227 https://github.com/JuliaLang/julia/pull/5227 for the open PR. The benchmark there suggests 2-3x improvement. There is a decent amount of low-hanging fruit, although "truly high performance garbage collection" means different things for different applications and LLVM is apparently not a good platform for generational GC. There are further possible improvements that are not strictly related to GC. We could determine that an array of the same size is being created on every iteration of the loop and allocate that memory only once. Ideally we'd automatically devectorize code to remove temporaries, but that is quite hard.