Perl power operator (**) benchmark. Especially, compare 2-powered with same-values-times. see: https://twitter.com/tooooooooomy/status/290368608213794816 (en: In perl square caluration, same-values-times calcration is fast rather than 2-powered caluration. It is a small piece of knowledge.)

perl-power-bench.pl

#!/usr/bin/perl
# xtetsuji 2013/01/13

use strict;
use warnings;

use Benchmark;

my $count = 50_000_000;

for my $x (-2, 0, 3, 5.5, 102, 7000) {
    print ".................... \$x=$x ....................\n";
    timethese($count, {
        'same values times' => sub {
            return $x * $x;
        },
        '2 powered' => sub {
            return $x ** 2;
        },
    });
    print "\n";
}

__END__

MEMO:
  Benchmark results are varios it on my environment...