test.pl

use strict;
use warnings;

use B;

sub simple {
    print "A";




    print "B";
}

sub complex {
    if (@_) {
        print "AA";
    }   
    else {
        print "AB";
    }   


    if (@_) {
        print "BA";
    }   
    else {
        print "BB";
    }   
}

sub lines {
    my @lines;
    my $cobj = B::svref_2object($_[0]);
    
    my $op = $cobj->START;
    while ($op) {
        if ($op->can('line')) {
            push @lines => $op->line;
        }   
        last unless $op->can('next');
        $op = $op->next;
    }   

    @lines = sort {$a <=> $b} @lines;
    return unless @lines;
    my ($start, $end) = ($lines[0], $lines[-1]);
    print "$start -> $end\n";
    return ($start, $end);
}

print "simple: ";
lines(\&simple);

print "complex: ";
lines(\&complex);

__END__

simple: 7 -> 12
complex: 16 -> 28