Do any languages / compilers utilize the x86 ENTER instruction with a nonzero nesting level?

Question

Those familiar with x86 assembly programming are very used to the typical function prologue / epilogue:

push ebp ; Save old frame pointer.
mov  ebp, esp ; Po         


        

Answer 1

enter is avoided in practice as it performs quite poorly - see the answers at "enter" vs "push ebp; mov ebp, esp; sub esp, imm" and "leave" vs "mov esp, ebp; pop ebp". There are a bunch of x86 instructions that are obsolete but are still supported for backwards compatibility reasons - enter is one of those. (leave is OK though, and compilers are happy to emit it.)

Implementing nested functions in full generality as in Python is actually a considerably more interesting problem than simply selecting a few frame management instructions - search for 'closure conversion' and 'upwards/downwards funarg problem' and you'll find many interesting discussions.

Note that the x86 was originally designed as a Pascal machine, which is why there are instructions to support nested functions (enter, leave), the pascal calling convention in which the callee pops a known number of arguments from the stack (ret K), bounds checking (bound), and so on. Many of these operations are now obsolete.