As you said it would be just a "reversed goto". So do it like you would do it normally but instead writing got to the origin of the jumo, write ComeFrom to the destination
10 ComeFrom 80
20 ... Do something when Codition is true
30 ...
...
...
70 If condition Do
80 ...
90 ComeFrom 30
(I'm not quite sure if i understood your problem correct)
Out of interest: Which language are you referring to ?