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<?php function f() { $a = "_SERVER"; var_dump(isset($$a)); } f(); $a = "_SERVER"; var_dump(isset($$a));
Finding entry points
Branch analysis from position: 0
1 jumps found. (Code = 62) Position 1 = -2
filename:       /in/WcL7P
function name:  (null)
number of ops:  8
compiled vars:  !0 = $a
line      #* E I O op                           fetch          ext  return  operands
-------------------------------------------------------------------------------------
    7     0  E >   INIT_FCALL                                               'f'
          1        DO_FCALL                                      0          
    9     2        ASSIGN                                                   !0, '_SERVER'
   10     3        INIT_FCALL                                               'var_dump'
          4        ISSET_ISEMPTY_VAR                             4  ~3      !0
          5        SEND_VAL                                                 ~3
          6        DO_ICALL                                                 
          7      > RETURN                                                   1

Function f:
Finding entry points
Branch analysis from position: 0
1 jumps found. (Code = 62) Position 1 = -2
filename:       /in/WcL7P
function name:  f
number of ops:  6
compiled vars:  !0 = $a
line      #* E I O op                           fetch          ext  return  operands
-------------------------------------------------------------------------------------
    3     0  E >   ASSIGN                                                   !0, '_SERVER'
    4     1        INIT_FCALL                                               'var_dump'
          2        ISSET_ISEMPTY_VAR                             4  ~2      !0
          3        SEND_VAL                                                 ~2
          4        DO_ICALL                                                 
    6     5      > RETURN                                                   null

End of function f

Generated using Vulcan Logic Dumper, using php 8.0.0


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