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<?php $x = null; # $y is not set var_dump($x); var_dump($y); var_dump(isset($x)); var_dump(isset($y));
Finding entry points
Branch analysis from position: 0
1 jumps found. (Code = 62) Position 1 = -2
filename:       /in/oWqXr
function name:  (null)
number of ops:  16
compiled vars:  !0 = $x, !1 = $y
line      #* E I O op                           fetch          ext  return  operands
-------------------------------------------------------------------------------------
    3     0  E >   ASSIGN                                                   !0, null
    6     1        INIT_FCALL                                               'var_dump'
          2        SEND_VAR                                                 !0
          3        DO_ICALL                                                 
    7     4        INIT_FCALL                                               'var_dump'
          5        SEND_VAR                                                 !1
          6        DO_ICALL                                                 
    9     7        INIT_FCALL                                               'var_dump'
          8        ISSET_ISEMPTY_CV                                 ~5      !0
          9        SEND_VAL                                                 ~5
         10        DO_ICALL                                                 
   10    11        INIT_FCALL                                               'var_dump'
         12        ISSET_ISEMPTY_CV                                 ~7      !1
         13        SEND_VAL                                                 ~7
         14        DO_ICALL                                                 
         15      > RETURN                                                   1

Generated using Vulcan Logic Dumper, using php 8.0.0


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