#!perl -w
use strict;
use Carp qw(croak);
use Data::Dumper;

sub get_value {
    my ($values) = @_;
    my $result = shift @$values;
    if (($result & 0b10000000) == 0) {
        # maybe $result < 127 is faster?
        return $result
    } elsif (($result & 0b11000000) == 0b10000000) {
        # maybe $result < 0b11000000 is faster?
        return (($result & 0b00111111) << 8) + shift @$values;
    } elsif (($result & 0b11000000) == 0b11000000) {
        # Assuming that Perl evaluates even "commutative" expressions
        # from left to right
        $result = (($result & 0b00111111) << 16)
                + ((shift @$values) << 8)
                + ((shift @$values));
        return $result;
    } else {
        # This should not happen anyway:
        croak sprintf "Invalid value found in input: %08b", $result;
    };
};

my @values = (0b01010101, # 85
              0b10101010, 0b10101010, # 10922
              0b11001100, 0b11001100, 0b11001100, # 838860
              0b00000000, # 0 as another simplicistic testcase
              );
while (@values) {
    print "$values[0] => ", get_value( \@values ),"\n";
};