Mark jumps into other functions as tail calls

[Xyene]

We can mark them with an argument, as well as a flow marker (arrow from one frame to the other).

We may need to special-case this for OCaml-only, depending on how this interacts with other languages.

[ahh]

You know that most C compilers etc also generate jmp tail calls (see gcc -foptimize-sibling-calls)?

Also I'm not sure what this buys us; I think the current UI of "foo; bar" on the same line is a pretty clear indication of what happened?

[cgaebel]

FWIW I also think the current display correctly communicates what's happening. When I last talked to Tudor about this he convinced me that it's worth at least trying it out to see what it looks like.