Php/docs/internals2.opcodes.fetch-func-arg

From Get docs

FETCH_FUNC_ARG

PHP code

<?php/* *  * opcode number: 92 */function foo($x){}$x = 1;$y = "x";$z = "foo";$z($$y);?>

PHP opcodes

Function name: (null)

Compiled variables: !0=$x, !1=$y, !2=$z

line # op fetch ext return operands
6 0 NOP        
10 1 ASSIGN       !0,1
11 2 ASSIGN       !1,'x'
12 3 ASSIGN       !2,'foo'
14 4 INIT_FCALL_BY_NAME       !2
  5 FETCH_FUNC_ARG local   $3 !1
  6 SEND_VAR       $3
  7 DO_FCALL_BY_NAME   1    
16 8 RETURN       1

Function name: foo

Compiled variables: !0=$x

line # op fetch ext return operands
6 0 RECV       1
8 1 RETURN       null