If you're working with XML, then you should consider using a cpan module like XML::Simple instead of hacking together a regex.

use Data::Dumper;
use XML::Simple;

use strict;

my $xml = '<funcCall>
<funcName>write</funcName>
<rhsValue>crlf</rhsValue>
<symConstant>loading</symConstant>
<symConstant>| |</symConstant>
<symConstant>lemmas</symConstant>
<symConstant>| |</symConstant>
<symConstant>for</symConstant>
<symConstant>| |</symConstant>
<variable>&lt;lx&gt;</variable>
<symConstant>| |</symConstant>
<symConstant>onto</symConstant>
<symConstant>| |</symConstant>
<variable>&lt;lms&gt;</variable>
</funcCall>';

my $ref = XMLin($xml);

print Dumper($ref);
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