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<?php $foo = "test"; var_dump($foo[0] ?? "default"); var_dump($foo[5] ?? "default"); var_dump(isset($foo[5]) ? $foo[5] : "default");
Finding entry points
Branch analysis from position: 0
2 jumps found. (Code = 43) Position 1 = 16, Position 2 = 19
Branch analysis from position: 16
1 jumps found. (Code = 42) Position 1 = 20
Branch analysis from position: 20
1 jumps found. (Code = 62) Position 1 = -2
Branch analysis from position: 19
1 jumps found. (Code = 62) Position 1 = -2
filename:       /in/lsoFA
function name:  (null)
number of ops:  23
compiled vars:  !0 = $foo
line      #* E I O op                               fetch          ext  return  operands
-----------------------------------------------------------------------------------------
    3     0  E >   ASSIGN                                                       !0, 'test'
    5     1        INIT_FCALL                                                   'var_dump'
          2        FETCH_DIM_IS                                         ~2      !0, 0
          3        COALESCE                                             ~3      ~2
          4        QM_ASSIGN                                            ~3      'default'
          5        SEND_VAL                                                     ~3
          6        DO_ICALL                                                     
    6     7        INIT_FCALL                                                   'var_dump'
          8        FETCH_DIM_IS                                         ~5      !0, 5
          9        COALESCE                                             ~6      ~5
         10        QM_ASSIGN                                            ~6      'default'
         11        SEND_VAL                                                     ~6
         12        DO_ICALL                                                     
    7    13        INIT_FCALL                                                   'var_dump'
         14        ISSET_ISEMPTY_DIM_OBJ                             0          !0, 5
         15      > JMPZ                                                         ~8, ->19
         16    >   FETCH_DIM_R                                          ~9      !0, 5
         17        QM_ASSIGN                                            ~10     ~9
         18      > JMP                                                          ->20
         19    >   QM_ASSIGN                                            ~10     'default'
         20    >   SEND_VAL                                                     ~10
         21        DO_ICALL                                                     
         22      > RETURN                                                       1

Generated using Vulcan Logic Dumper, using php 8.5.0


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