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<?php echo substr(null, 0, 2); echo substr(null, -4); echo substr(array(), 0, 2);
Finding entry points
Branch analysis from position: 0
1 jumps found. (Code = 62) Position 1 = -2
filename:       /in/oj6cC
function name:  (null)
number of ops:  18
compiled vars:  none
line      #* E I O op                           fetch          ext  return  operands
-------------------------------------------------------------------------------------
    3     0  E >   INIT_FCALL                                               'substr'
          1        SEND_VAL                                                 null
          2        SEND_VAL                                                 0
          3        SEND_VAL                                                 2
          4        DO_ICALL                                         $0      
          5        ECHO                                                     $0
    4     6        INIT_FCALL                                               'substr'
          7        SEND_VAL                                                 null
          8        SEND_VAL                                                 -4
          9        DO_ICALL                                         $1      
         10        ECHO                                                     $1
    5    11        INIT_FCALL                                               'substr'
         12        SEND_VAL                                                 <array>
         13        SEND_VAL                                                 0
         14        SEND_VAL                                                 2
         15        DO_ICALL                                         $2      
         16        ECHO                                                     $2
         17      > RETURN                                                   1

Generated using Vulcan Logic Dumper, using php 8.0.0


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