Multiple URL's to a single VS with ASM

So currently, I'm using iRules to send traffic to different pools, thus allowing us to use a single IP a little more efficiently. I would like to also be able to have these applications protected by ASM so I'm seeking a little guidance as to how to do this with the current iRule, or possibly using a policy if it's faster? Thanks in advance.

when HTTP_REQUEST {
    switch [string tolower [HTTP::host]] {
        "abc.com" { pool abc.com }
        "def.abc.com" { pool def.abc.com }
        "ghi.abc.com" { pool ghi.abc.com }
    }
}