@begin: scope:[]  from
  [0] phi()
  to:@1
@1: scope:[]  from @begin
  [1] phi()
  [2] call main 
  to:@end
@end: scope:[]  from @1
  [3] phi()
main: scope:[main]  from @1
  [4] phi()
  to:main::@3
main::@3: scope:[main]  from main main::@4
  [5] (byte) main::i#9 ← phi( main::@4/(byte) main::i#1 main/(byte) 0 )
  [6] *((const byte*) main::screen#0 + (byte) main::i#9) ← (byte) '*'
  to:main::@2
main::@2: scope:[main]  from main::@1 main::@3 main::@4
  [7] (byte) main::i#5 ← phi( main::@1/(byte) main::i#1 main::@3/(byte) main::i#9 main::@4/(byte) main::i#1 )
  [8] (byte) main::i#1 ← ++ (byte) main::i#5
  [9] if((byte) main::i#1!=(byte) $15) goto main::@1
  to:main::@return
main::@return: scope:[main]  from main::@2
  [10] return 
  to:@return
main::@1: scope:[main]  from main::@2
  [11] (byte~) main::$6 ← (byte) main::i#1 & (byte) 1
  [12] if((byte) main::i#1>=(byte) $a) goto main::@2
  to:main::@4
main::@4: scope:[main]  from main::@1
  [13] if((byte~) main::$6!=(byte) 0) goto main::@2
  to:main::@3
