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<?php var_dump( substr_count ('haystack', 'tack', 0, 0), substr('haystack', 0, 0) );
Finding entry points
Branch analysis from position: 0
1 jumps found. (Code = 62) Position 1 = -2
filename:       /in/bAu27
function name:  (null)
number of ops:  13
compiled vars:  none
line      #* E I O op                               fetch          ext  return  operands
-----------------------------------------------------------------------------------------
    3     0  E >   INIT_FCALL                                                   'var_dump'
    4     1        INIT_FCALL                                                   'substr_count'
          2        SEND_VAL                                                     'haystack'
          3        SEND_VAL                                                     'tack'
          4        SEND_VAL                                                     0
          5        SEND_VAL                                                     0
          6        DO_ICALL                                             $0      
          7        SEND_VAR                                                     $0
    5     8        FRAMELESS_ICALL_3                substr              ~1      'haystack', 0
          9        OP_DATA                                                      0
         10        SEND_VAL                                                     ~1
    3    11        DO_ICALL                                                     
    6    12      > RETURN                                                       1

Generated using Vulcan Logic Dumper, using php 8.5.0


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