#!/usr/bin/perl 
use strict;
use warnings;
use Data::Dumper;

# No need to double quoted
my $inp_row = q{per|l|mo|nks|ro|ck|s};
my $de = q{|};
my $count = 0;
my $row;

$count++ for $inp_row =~ /\Q$de/g;

print "Delim: $de\nCount: $count\n";

push @{$row}, split /\Q$de/, $inp_row;

print Dumper $row;

##</code><code>##

Output:
Delim: |
Count: 6
$VAR1 = [
          'per',
          'l',
          'mo',
          'nks',
          'ro',
          'ck',
          's'
        ];