my ($procedure, $function);
DISPATCH: {
    if ($procName eq "PAR_REPORTS_POS.SUN_PRC_AT_I_POSM1D007")
    {
        $function = $dbh->prepare("BEGIN $procName(?, ?); END;");
        $function->bind_param(1, \$retcode, 100); #? 100?
        $function->bind_param(2, \$retmsg, 100);
        last DISPATCH;
    }
    if ($procName eq "PAR_REPORTS_POS.SUN_PRC_AT_I_POSM1W001")
    (
        $function = $dbh->prepare("BEGIN $procName(?, ?, ?, ?); END;");
        $function->bind_param(1, \$retcode, 100); #? 100?
        $function->bind_param(2, \$retmsg, 100);
        $function->bind_param(3, \$finRepId, SQL_VARCHAR);
        $function->bind_param(4, \$showPendingPolicies, SQL_VARCHAR);
        last DISPATCH;
    }
    # and so on...
} #close block labelled DISPATCH;
$function->execute;