@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()
  [5] call malloc 
  [6] (void*) malloc::return#0 ← (void*) malloc::return#2
  to:main::@1
main::@1: scope:[main]  from main
  [7] (void*) main::buf1#0 ← (void*) malloc::return#0
  [8] call malloc 
  [9] (void*) malloc::return#1 ← (void*) malloc::return#2
  to:main::@2
main::@2: scope:[main]  from main::@1
  [10] (void*) main::buf2#0 ← (void*) malloc::return#1
  [11] *((byte*)(void*) main::buf1#0) ← (byte) 'a'
  [12] *((byte*)(void*) main::buf2#0) ← (byte) 'b'
  [13] *((const byte*) SCREEN#0) ← *((byte*)(void*) main::buf1#0)
  [14] *((const byte*) SCREEN#0+(byte) 1) ← *((byte*)(void*) main::buf2#0)
  to:main::@return
main::@return: scope:[main]  from main::@2
  [15] return 
  to:@return
malloc: scope:[malloc]  from main main::@1
  [16] (byte*) heap_head#10 ← phi( main/(byte*) 49152 main::@1/(byte*) heap_head#11 )
  [17] (byte*) heap_head#11 ← ++ (byte*) heap_head#10
  [18] (void*) malloc::return#2 ← (void*)(byte*) heap_head#11
  to:malloc::@return
malloc::@return: scope:[malloc]  from malloc
  [19] return 
  to:@return
