Try B::Xref on your script through the O module — meaning you load the O module; B::Xref is like a driver for it; documentation for it is in the latter. The command line syntax basically is:

perl -MO=Xref foo.pl
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This will produce a report on what is defined and/or used where. Whether it is readable, now, that is another question. You can write a Perl script to post-process this output, turning into something that you like, and for that, the -r option might be interesting because now you get a table in text format, instead of an outline. Now, the command line looks something like:

perl -MO=Xref,-r foo.pl
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I don't know if anybody has written something to produce ressembling what you want, and if so, whether he/she has made it available. So this is a public call: make yourself known!...