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<?php function u ($x = 'zz') { return $x; } var_dump (u (null));
Finding entry points
Branch analysis from position: 0
1 jumps found. (Code = 62) Position 1 = -2
filename:       /in/WXlMV
function name:  (null)
number of ops:  7
compiled vars:  none
line      #* E I O op                           fetch          ext  return  operands
-------------------------------------------------------------------------------------
    8     0  E >   INIT_FCALL                                               'var_dump'
          1        INIT_FCALL                                               'u'
          2        SEND_VAL                                                 null
          3        DO_FCALL                                      0  $0      
          4        SEND_VAR                                                 $0
          5        DO_ICALL                                                 
          6      > RETURN                                                   1

Function u:
Finding entry points
Branch analysis from position: 0
1 jumps found. (Code = 62) Position 1 = -2
filename:       /in/WXlMV
function name:  u
number of ops:  3
compiled vars:  !0 = $x
line      #* E I O op                           fetch          ext  return  operands
-------------------------------------------------------------------------------------
    3     0  E >   RECV_INIT                                        !0      'zz'
    5     1      > RETURN                                                   !0
    6     2*     > RETURN                                                   null

End of function u

Generated using Vulcan Logic Dumper, using php 8.0.0


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