my @acc_array;
foreach(@somearray){

  if($cond ==1) {
   
   my $a = Benchmark::Timer->new(skip => 0);
   $a->start('tag');
   @acc_array = &some_long_running_func($_);
   $a->stop('tag');
   print $a->report;

  }

}

##</code><code>##

Processed: 1
tag  still running at mycode.pl line 223
Processed: 2
tag still running at mycode.pl line 223