3v4l.org

run code in 300+ PHP versions simultaneously
<?php class A { public $b; } $a = new A; $a->b = new A; $a->b->b = 1; if (isset($a->b->b)) { echo 'exists'; }
Finding entry points
Branch analysis from position: 0
2 jumps found. (Code = 43) Position 1 = 13, Position 2 = 14
Branch analysis from position: 13
1 jumps found. (Code = 62) Position 1 = -2
Branch analysis from position: 14
filename:       /in/NAjBk
function name:  (null)
number of ops:  15
compiled vars:  !0 = $a
line      #* E I O op                           fetch          ext  return  operands
-------------------------------------------------------------------------------------
    7     0  E >   NEW                                              $1      'A'
          1        DO_FCALL                                      0          
          2        ASSIGN                                                   !0, $1
    8     3        NEW                                              $5      'A'
          4        DO_FCALL                                      0          
          5        ASSIGN_OBJ                                               !0, 'b'
          6        OP_DATA                                                  $5
    9     7        FETCH_OBJ_W                                      $7      !0, 'b'
          8        ASSIGN_OBJ                                               $7, 'b'
          9        OP_DATA                                                  1
   11    10        FETCH_OBJ_IS                                     ~9      !0, 'b'
         11        ISSET_ISEMPTY_PROP_OBJ                                   ~9, 'b'
         12      > JMPZ                                                     ~10, ->14
   12    13    >   ECHO                                                     'exists'
   13    14    > > RETURN                                                   1

Class A: [no user functions]

Generated using Vulcan Logic Dumper, using php 8.0.0


preferences:
169.95 ms | 1393 KiB | 13 Q