Why not take the last step too?

$ cat test.pl
use 5.16.2;
use warnings;
use Benchmark  qw( cmpthese );
use List::Util qw( reduce sum );

my $count   = 12;
my $address = "A42187B56F";
my $data    = "39AD0D96D51CD3";

my $r = sub {
    reduce { $a + $b }
    map    { hex $_  }
    ($count, $address =~ m/../g, $data =~ m/../g);
    };

my $s = sub {
    sum map { hex } $count,
                   (unpack "(A2)*", $address),
                   (unpack "(A2)*", $data);
    };

say $r->();
say $s->();

cmpthese (-2, { LUreduce => $r, LUsum => $s });
$ perl test.pl
1487
1487
             Rate LUreduce    LUsum
LUreduce 216392/s       --     -40%
LUsum    359162/s      66%       --
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