You could use the magical form of goto.

From perlsyn

The goto-&NAME form is highly magical, and substitutes a call to the n
+amed subroutine for the currently running subroutine. This is used by
+ AUTOLOAD() subroutines that wish to load another subroutine and then
+ pretend that the other subroutine had been called in the first place
+ (except that any modifications to @_ in the current subroutine are p
+ropagated to the other subroutine.) After the goto, not even caller()
+ will be able to tell that this routine was called first.
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So this should work (I think).

sub callit
{
    goto &$p;
}
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