As long as you are not doing anything weird/tricky with subroutine references, Hook::LexWrap might be something to give you a start. Hook::LexWrap allows you to install (and remove) wrappers around Perl subroutines (much like the .wrap method on subroutines in Perl 6). So now all you need is a list of your function names within your module - this is possible by looking through the namespace of that module :

use My::Module;
print join ",", sort keys %{My::Module::};
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The special, unnamed hash %My::Module:: (yes, the last two colons are part of the name) contains all the global (and thus still wrappable) names. Now you still have to find out which of these are subroutines and which aren't (*{My::Module::varname}{CODE} is defined) and that should be it. There are some snippets here, that do exactly that, but I couldn't find them quickly ...

perl -MHTTP::Daemon -MHTTP::Response -MLWP::Simple -e ' ;    # The  
$d = new HTTP::Daemon and fork and getprint $d->url and exit;#spider
($c = $d->accept())->get_request(); $c->send_response( new   #in the
HTTP::Response(200,$_,$_,qq(Just another Perl hacker\n))); ' #  web
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