Opcode Descriptions and Examples
PHP Manual

ASSIGN_SL

PHP code

<?php
/*
 * Shift result by value1 bits to left and store in variable indicated by result
 * opcode number: 28
 */
$a <<= 3;
?>

PHP opcodes

Function name: (null)

Compiled variables: !0=$a

line#op fetchextreturn operands
60 ASSIGN_SL     !0,3
71 RETURN     1

Opcode Descriptions and Examples
PHP Manual