Opcode Descriptions and Examples
PHP Manual

BW_NOT

PHP code

<?php
/*
 * Bit-wise not of "value"
 * opcode number: 12
 */
echo ~15;
?>

PHP opcodes

Function name: (null)

Compiled variables: none

line#op fetchextreturn operands
60 BW_NOT   ~0 15
 1 ECHO     ~0
72 RETURN     1

Opcode Descriptions and Examples
PHP Manual