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<?php $sub = substr('abcdef', 4, -4); if ($sub === false) { echo 'fail'; } else { echo 'do somthing with $sub'; }
Finding entry points
Branch analysis from position: 0
2 jumps found. (Code = 43) Position 1 = 5, Position 2 = 7
Branch analysis from position: 5
1 jumps found. (Code = 42) Position 1 = 8
Branch analysis from position: 8
1 jumps found. (Code = 62) Position 1 = -2
Branch analysis from position: 7
1 jumps found. (Code = 62) Position 1 = -2
filename:       /in/Ln9g3
function name:  (null)
number of ops:  9
compiled vars:  !0 = $sub
line      #* E I O op                               fetch          ext  return  operands
-----------------------------------------------------------------------------------------
    3     0  E >   FRAMELESS_ICALL_3                substr              ~1      'abcdef', 4
          1        OP_DATA                                                      -4
          2        ASSIGN                                                       !0, ~1
    5     3        TYPE_CHECK                                        4          !0
          4      > JMPZ                                                         ~3, ->7
    6     5    >   ECHO                                                         'fail'
    5     6      > JMP                                                          ->8
    8     7    >   ECHO                                                         'do+somthing+with+%24sub'
    9     8    > > RETURN                                                       1

Generated using Vulcan Logic Dumper, using php 8.5.0


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