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> Remember the CS assembly course where we learned that a function
> call involves saving all the status (register values), and
> returning from a function call means to recover them?
That depends entirely on the compiler implementation. If your
compiler carries variable values &etc in registers for efficiency,
then yes, you have to save them when you make a function call.
(Because you don't know if the function will write over those values
in the registers.) But that assumes a reasonably sophisticated
optimizing compiler, and I think it's safe to assume the EL compiler
doesn't fall into that category.
If the compiler is a simple non-optimizing compiler, then there may
not be ANY registers that need to be saved, other than the obvious
PC, stack, etc registers that are automatically saved/restored by the
JSR (or whatever) instruction.
In EL's case I'd guess there might be some overhead in *setting up* a
function, once you're in it. But actually calling a function might
not take much overhead at all.
Gary
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