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<?php $a = NULL; $b = 1; $c = 2; echo $a ?? $b; // 1 echo $c ?? $b; // 2 echo $a ?? $b ?? $c; // 1 echo $a ?? $x ?? $c; // 2
Finding entry points
Branch analysis from position: 0
1 jumps found. (Code = 62) Position 1 = -2
filename:       /in/SP2f5
function name:  (null)
number of ops:  20
compiled vars:  !0 = $a, !1 = $b, !2 = $c, !3 = $x
line      #* E I O op                           fetch          ext  return  operands
-------------------------------------------------------------------------------------
    3     0  E >   ASSIGN                                                   !0, null
    4     1        ASSIGN                                                   !1, 1
    5     2        ASSIGN                                                   !2, 2
    7     3        COALESCE                                         ~7      !0
          4        QM_ASSIGN                                        ~7      !1
          5        ECHO                                                     ~7
    8     6        COALESCE                                         ~8      !2
          7        QM_ASSIGN                                        ~8      !1
          8        ECHO                                                     ~8
    9     9        COALESCE                                         ~9      !0
         10        COALESCE                                         ~10     !1
         11        QM_ASSIGN                                        ~10     !2
         12        QM_ASSIGN                                        ~9      ~10
         13        ECHO                                                     ~9
   10    14        COALESCE                                         ~11     !0
         15        COALESCE                                         ~12     !3
         16        QM_ASSIGN                                        ~12     !2
         17        QM_ASSIGN                                        ~11     ~12
         18        ECHO                                                     ~11
         19      > RETURN                                                   1

Generated using Vulcan Logic Dumper, using php 8.0.0


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