use strict;
use warnings;

use Benchmark qw( cmpthese );

sub attrib_copy   { my ($self) = @_; $self->{attrib} }
sub attrib_nocopy {                  $_[0]->{attrib} }

our $self = bless({ attrib => 'some_value' });

my %tests = (
    copy          => 'my $x = do { local @_ = $self; &main::attrib_copy };',
    nocopy        => 'my $x = do { local @_ = $self; &main::attrib_nocopy };',
    inline_copy   => 'my $x = do { local @_ = $self; my ($self) = @_; $self->{attrib} };',
    inline_nocopy => 'my $x = do { local @_ = $self;                  $_[0]->{attrib} };',
);

$_ = 'use strict; use warnings; our $self; ' . $_
    for values %tests;

cmpthese(-3, \%tests);