> And the Java ones don't look anything at all like typical Java, either. Which ones do you mean? > But no, the C/C++ ones have not been all manually vectoriz

> And the Java ones don't look anything at all like typical Java, either. Which ones do you mean? > But no, the C/C++ ones have not been all manually vectorized to death. True. > The binary-trees one, for example, is a fairly clean C++ implementation, and runs in less than half the time using less than half the memory of the Java version. Unfortunately I can't benchmark this myself because it uses some library I've never heard of. The numbers on the Debian site look pretty outdated, Java binary-trees takes about 1800 ms on my machine. And about 1450 ms after letting it warm up. > AOTs are really good. So are JITs, but we are both really deep in hand-waving territory here. > Return types consistently being on the stack without requiring escape analysis is really good. The fast path of object allocation is bumping a pointer into an allocation buffer and checking it against the buffer's limit. Objects that are short-lived enough that you would want to return them by value in C++ will usually never leave the allocation buffer. So it's not the exact same thing as allocating on the call stack, but it's not far.