php 如何实现以下混淆方法？

[loome]

代码太长，只截取一小部分

${"GLOBALS"}["ouhmzylxfbji"] = "filterElement";
${"GLOBALS"}["qxyjofg"] = "filterElements";
${"GLOBALS"}["ytruvymrot"] = "createdDom";
${"GLOBALS"}["jzduoky"] = "nextE";
${"GLOBALS"}["bcozrflmociy"] = "prevE";
${"GLOBALS"}["baqfimelwow"] = "startPindex";
${"GLOBALS"}["ytsyscwjsgg"] = "pNum";

if (isset($_GET["login_url"]) && ($_GET["login_url"] != "")) {
    ${"GLOBALS"}["cjdkgb"] = "inputs";
    $mewfoqb = "html_string";
    ${"GLOBALS"}["qijxdddxun"] = "html_string";
    ${${"GLOBALS"}["ugsfyuseif"]} = $_GET["login_url"];
    ${"GLOBALS"}["stfjwikm"] = "login_url";
    ${${"GLOBALS"}["qijxdddxun"]} = get_html_string_apf(${${"GLOBALS"}["stfjwikm"]}, Method);
    ${${"GLOBALS"}["xsjlyd"]} = getHtmlCharset_apf(${${"GLOBALS"}["vxiintkjiccb"]});
    ${${"GLOBALS"}["seqvxcxer"]} = str_get_html_apf(${$mewfoqb}, ${${"GLOBALS"}["xsjlyd"]});
    ${${"GLOBALS"}["cjdkgb"]} = $dom->find("form input[name]");

使用${"GLOBALS"}["*"]=** 方式替换所有变量，${"GLOBALS"}["*"]里的*好像是随机字符，请问此种方式是如何实现的？