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<?php $a = 'abcdef'; $x = substr($a, 0, strlen($a)-1);echo $x;echo "\n"; $y = substr($x, 0, strlen($x)-1);echo strlen('a');
Finding entry points
Branch analysis from position: 0
1 jumps found. (Code = 62) Position 1 = -2
filename:       /in/3p93f
function name:  (null)
number of ops:  21
compiled vars:  !0 = $a, !1 = $x, !2 = $y
line      #* E I O op                           fetch          ext  return  operands
-------------------------------------------------------------------------------------
    2     0  E >   ASSIGN                                                   !0, 'abcdef'
    3     1        INIT_FCALL                                               'substr'
          2        SEND_VAR                                                 !0
          3        SEND_VAL                                                 0
          4        STRLEN                                           ~4      !0
          5        SUB                                              ~5      ~4, 1
          6        SEND_VAL                                                 ~5
          7        DO_ICALL                                         $6      
          8        ASSIGN                                                   !1, $6
          9        ECHO                                                     !1
         10        ECHO                                                     '%0A'
    4    11        INIT_FCALL                                               'substr'
         12        SEND_VAR                                                 !1
         13        SEND_VAL                                                 0
         14        STRLEN                                           ~8      !1
         15        SUB                                              ~9      ~8, 1
         16        SEND_VAL                                                 ~9
         17        DO_ICALL                                         $10     
         18        ASSIGN                                                   !2, $10
         19        ECHO                                                     1
         20      > RETURN                                                   1

Generated using Vulcan Logic Dumper, using php 8.0.0


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