void main()
main: scope:[main]  from
  [0] phi()
  to:main::@1
main::@1: scope:[main]  from main main::@2
  [1] framedone#1 = phi( main/true, main::@2/false )
  to:main::@2
main::@2: scope:[main]  from main::@1 main::@2
  [2] if(framedone#1) goto main::@1
  to:main::@2