Opcode Descriptions and Examples
PHP 手册

PRE_INC_OBJ

PHP code

<?php
/*
 * 
 * opcode number: 132
 */
$obj = new A();
++
$obj->num;
?>

PHP opcodes

Function name: (null)

Compiled variables: !0=$obj

line#op fetchextreturn operands
60 ZEND_FETCH_CLASS   :0 'A'
 1 NEW   $1 :0
 2 DO_FCALL_BY_NAME  0   
 3 ASSIGN     !0,$1
74 ZEND_PRE_INC_OBJ     !0,'num'
85 RETURN     1

Opcode Descriptions and Examples
PHP 手册