Pretty simple question. Does an ALU internally always do multiple operations like add, sub, div, mul, ... and you simply have to specify which result you want to return? I was told that it does that, but I wasn't able to find proof of that being correct. Though I found some graphics containing a multiplexer which from my understanding has basically one output and multiple inputs and by setting some special inputs you can pipe on input to the output. So that might be it, but I don't know enough about that to fully understand it.
I'm specifically wondering about the 8085 architecture's ALU in case it is special, but I'd also like to know about other ALUs if there are different ones.