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PHP Manual

SWITCH_FREE

PHP code

<?php
/*
 * Release the allocated space of "value"?
 * opcode number: 49
 */
$a = array(1,2,3);
foreach(
$a as $num){
    print 
$num;
}
?>

PHP opcodes

Function name: (null)

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

line#op fetchextreturn operands
60 INIT_ARRAY? ?~0 1
?1 ADD_ARRAY_ELEMENT? ?~0 2
?2 ADD_ARRAY_ELEMENT? ?~0 3
?3 ASSIGN? ?? !0,~0
74 FE_RESET? ?$2 !0,->11
?5 FE_FETCH? ?$3 $2,->11
?6 ZEND_OP_DATA? ?? ?
?7 ASSIGN? ?? !1,$3
88 PRINT? ?~5 !1
?9 FREE? ?? ~5
910 JMP? ?? ->5
?11 SWITCH_FREE? ?? $2
1012 RETURN? ?? 1

オペコード一覧
PHP Manual