use Data::Dumper;
use strict;


sub my_split {
    local $_ = shift;
    my $abc;
    s/(('|").*?\2)/ ($abc = $1) =~ s!\s+!\cA!g; $abc /ge; #!"
    grep{s/\cA/ /g, $_}split/\s+/;
}

my @pieces = my_split q/one "two three" four "five six seven" eight/;
print Dumper(\@pieces);
[download]