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<?php $i = 0; function is_cyclic(array &$array) { global $i; // Exit when too deep. if (++$i > 10) exit; echo "Iteration $i:\n"; echo "Memory usage: " . memory_get_usage() . "\n"; echo "\n"; $lastKey = array_key_last($array); if ($lastKey === null) { // Array is empty return false; } static $marker; if ($marker === null) { $marker = new stdClass(); } if ($array[$lastKey] === $marker) { return true; } $array[] = $marker; foreach ($array as &$item) { if (is_array($item) && is_cyclic($item)) { //array_pop($array); return true; } } //array_pop($array); return false; } function craft_bomb() { $array = [range(1, 1000), [range(1, 512), 3]]; $array[1][1] = &$array; return $array; } $bomb = craft_bomb(); is_cyclic($bomb);
Finding entry points
Branch analysis from position: 0
1 jumps found. (Code = 62) Position 1 = -2
filename:       /in/k9s3V
function name:  (null)
number of ops:  8
compiled vars:  !0 = $i, !1 = $bomb
line      #* E I O op                           fetch          ext  return  operands
-------------------------------------------------------------------------------------
    3     0  E >   ASSIGN                                                   !0, 0
   45     1        INIT_FCALL                                               'craft_bomb'
          2        DO_FCALL                                      0  $3      
          3        ASSIGN                                                   !1, $3
   46     4        INIT_FCALL                                               'is_cyclic'
          5        SEND_REF                                                 !1
          6        DO_FCALL                                      0          
          7      > RETURN                                                   1

Function is_cyclic:
Finding entry points
Branch analysis from position: 0
2 jumps found. (Code = 43) Position 1 = 5, Position 2 = 6
Branch analysis from position: 5
1 jumps found. (Code = 79) Position 1 = -2
Branch analysis from position: 6
2 jumps found. (Code = 43) Position 1 = 22, Position 2 = 23
Branch analysis from position: 22
1 jumps found. (Code = 62) Position 1 = -2
Branch analysis from position: 23
2 jumps found. (Code = 43) Position 1 = 26, Position 2 = 29
Branch analysis from position: 26
2 jumps found. (Code = 43) Position 1 = 32, Position 2 = 33
Branch analysis from position: 32
1 jumps found. (Code = 62) Position 1 = -2
Branch analysis from position: 33
2 jumps found. (Code = 125) Position 1 = 36, Position 2 = 47
Branch analysis from position: 36
2 jumps found. (Code = 126) Position 1 = 37, Position 2 = 47
Branch analysis from position: 37
2 jumps found. (Code = 46) Position 1 = 39, Position 2 = 43
Branch analysis from position: 39
2 jumps found. (Code = 43) Position 1 = 44, Position 2 = 46
Branch analysis from position: 44
1 jumps found. (Code = 62) Position 1 = -2
Branch analysis from position: 46
1 jumps found. (Code = 42) Position 1 = 36
Branch analysis from position: 36
Branch analysis from position: 43
Branch analysis from position: 47
1 jumps found. (Code = 62) Position 1 = -2
Branch analysis from position: 47
Branch analysis from position: 29
filename:       /in/k9s3V
function name:  is_cyclic
number of ops:  50
compiled vars:  !0 = $array, !1 = $i, !2 = $lastKey, !3 = $marker, !4 = $item
line      #* E I O op                           fetch          ext  return  operands
-------------------------------------------------------------------------------------
    5     0  E >   RECV                                             !0      
    7     1        BIND_GLOBAL                                              !1, 'i'
   10     2        PRE_INC                                          ~5      !1
          3        IS_SMALLER                                               10, ~5
          4      > JMPZ                                                     ~6, ->6
          5    > > EXIT                                                     
   12     6    >   ROPE_INIT                                     3  ~8      'Iteration+'
          7        ROPE_ADD                                      1  ~8      ~8, !1
          8        ROPE_END                                      2  ~7      ~8, '%3A%0A'
          9        ECHO                                                     ~7
   13    10        INIT_FCALL                                               'memory_get_usage'
         11        DO_ICALL                                         $10     
         12        CONCAT                                           ~11     'Memory+usage%3A+', $10
         13        CONCAT                                           ~12     ~11, '%0A'
         14        ECHO                                                     ~12
   14    15        ECHO                                                     '%0A'
   16    16        INIT_FCALL                                               'array_key_last'
         17        SEND_VAR                                                 !0
         18        DO_ICALL                                         $13     
         19        ASSIGN                                                   !2, $13
   17    20        TYPE_CHECK                                    2          !2
         21      > JMPZ                                                     ~15, ->23
   19    22    > > RETURN                                                   <false>
   21    23    >   BIND_STATIC                                              !3
   22    24        TYPE_CHECK                                    2          !3
         25      > JMPZ                                                     ~16, ->29
   23    26    >   NEW                                              $17     'stdClass'
         27        DO_FCALL                                      0          
         28        ASSIGN                                                   !3, $17
   25    29    >   FETCH_DIM_R                                      ~20     !0, !2
         30        IS_IDENTICAL                                             !3, ~20
         31      > JMPZ                                                     ~21, ->33
   26    32    > > RETURN                                                   <true>
   28    33    >   ASSIGN_DIM                                               !0
         34        OP_DATA                                                  !3
   29    35      > FE_RESET_RW                                      $23     !0, ->47
         36    > > FE_FETCH_RW                                              $23, !4, ->47
   30    37    >   TYPE_CHECK                                  128  ~24     !4
         38      > JMPZ_EX                                          ~24     ~24, ->43
         39    >   INIT_FCALL_BY_NAME                                       'is_cyclic'
         40        SEND_VAR_EX                                              !4
         41        DO_FCALL                                      0  $25     
         42        BOOL                                             ~24     $25
         43    > > JMPZ                                                     ~24, ->46
   32    44    >   FE_FREE                                                  $23
         45      > RETURN                                                   <true>
   29    46    > > JMP                                                      ->36
         47    >   FE_FREE                                                  $23
   36    48      > RETURN                                                   <false>
   37    49*     > RETURN                                                   null

End of function is_cyclic

Function craft_bomb:
Finding entry points
Branch analysis from position: 0
1 jumps found. (Code = 62) Position 1 = -2
filename:       /in/k9s3V
function name:  craft_bomb
number of ops:  18
compiled vars:  !0 = $array
line      #* E I O op                           fetch          ext  return  operands
-------------------------------------------------------------------------------------
   40     0  E >   INIT_FCALL                                               'range'
          1        SEND_VAL                                                 1
          2        SEND_VAL                                                 1000
          3        DO_ICALL                                         $1      
          4        INIT_ARRAY                                       ~2      $1
          5        INIT_FCALL                                               'range'
          6        SEND_VAL                                                 1
          7        SEND_VAL                                                 512
          8        DO_ICALL                                         $3      
          9        INIT_ARRAY                                       ~4      $3
         10        ADD_ARRAY_ELEMENT                                ~4      3
         11        ADD_ARRAY_ELEMENT                                ~2      ~4
         12        ASSIGN                                                   !0, ~2
   41    13        FETCH_DIM_W                                      $6      !0, 1
         14        FETCH_DIM_W                                      $7      $6, 1
         15        ASSIGN_REF                                               $7, !0
   42    16      > RETURN                                                   !0
   43    17*     > RETURN                                                   null

End of function craft_bomb

Generated using Vulcan Logic Dumper, using php 8.0.0


preferences:
154.37 ms | 1407 KiB | 21 Q