
void main()
main: scope:[main]  from
  [0] main::a#0 = *SCREEN
  [1] main::$0 = main::a#0 + 1
  [2] *(SCREEN+1) = main::$0
  to:main::@return
main::@return: scope:[main]  from main
  [3] return 
  to:@return
