my $tc = $xml->{dut}->[0]->{tc};
foreach my $id (keys %$tc) {
   if ($tc->{$id}->{result} eq 'Passed'){$Passed++;}
   if ($tc->{$id}->{result} eq 'Warnings'){$Warnings++;}
   if ($tc->{$id}->{result} eq 'Failed'){$Failed++;}
}
[download]

Dumping the $xml object with e.g. Data::Dumper helps in such a case.

_($_=" "x(1<<5)."?\n".q·/)Oo.  G°\        /
                              /\_¯/(q    /
----------------------------  \__(m.====·.(_("always off the crowd"))."·
");sub _{s./.($e="'Itrs `mnsgdq Gdbj O`qkdq")=~y/"-y/#-z/;$e.e && print}