=> COFF On 2022-Jan-30 10:07:15 -0800, Dan Stromberg <drsalists(a)gmail.com> wrote: A bit late to the party but my 2¢: I think it's fairly clear that both UCSD Pascal and Java are compiled - to binary machine code for a p-code machine or JVM respectively. That's no different to compiling (eg) C to PDP-11 or amd64 binary machine code. As for how the machine code is executed: * p-code was typically interpreted but (as mentioned elsewhere) there were a number of hardware implementions. * Java bytecode is often executed using a mixture of interpretation and (JIT) compilation to the host's machine code. Again there are a number of hardware implementations. And looking the other way, all (AFAIK) PDP-11's were microcoded, therefore you could equally well say that PDP-11 machine code is being interpreted by the microcode on a "real" PDP-11. And, nowadays, PDP-11 machine code is probably more commonly interpreted using something like simh than being run on a hardware PDP-11. Typical amd64 implementations are murkier - with machine code being further converted ("compiled"?) into a variable number of micro-ops that have their own caches and are then executed on the actual CPU. (And, going back in time, the Transmeta Crusoe explicity did JIT conversion from iA32 machine code to its own proprietary machine code). -- Peter Jeremy