I think you may be confused. At the point at which you compile this, you are no longer dealing with JVM bytecode, but your own IR (translated from JVM bytecode

I think you may be confused. At the point at which you compile this, you are no longer dealing with JVM bytecode, but your own IR (translated from JVM bytecode), and can do whatever you want. Thus, you are not limited by what the JVM has in terms of instructions. (and in general, you never are. You are only limited by correctness of program execution) If you want to support it at the bytecode level, yes, what you are suggesting is correct, but it doesn't have to be done this way at all, and rarely is in any language. In general, having to muck up source-code to get optimal data-layouts is a non-starter. Second, the actual optimal data layouts are rarely what programmers think they are due to cache/other complications (it's usually some very complicated nested struct layout with explicit packing and unions in various places) In any case, i believe my base point stands: There is nothing that stops java from being fast in these cases, because you don't need any support from bytecode to do it.