while (<>)
{
       ..... 
       if(/...../)
       {
            ...
       }
       elsif(/...../)
       {
            ...
       }

       .....
       # and a bunch more regexps
       increment_counters(...);
       .....
}
sub increment_counters
{
       ....
       if(/...../)
       {
              .....
              next;  # note that this nexts the above loop
       }

       if(/..../)
       {
              ....
              next;
       }
       ......
}

##</code><code>##

if( qr/..../ )

##</code><code>##

my $date = qr/...../;
if(m/$date/)
{
    .....
}