Opcode Descriptions and Examples
PHP Manual

FETCH_R

PHP code

<?php
/*
 * Fetch the value of the varible of "name" to assign it to a variable?  Read-only?
 * opcode number: 80
 */
$x 1;
$a 'x';
echo $
$a;
?>

PHP opcodes

Function name: (null)

Compiled variables: !0=$x, !1=$a

line#op fetchextreturn operands
60 ASSIGN     !0,1
71 ASSIGN     !1,'x'
82 FETCH_Rlocal  $2 !1
 3 ECHO     $2
94 RETURN     1

Opcode Descriptions and Examples
PHP Manual