B::Terse
See the current Perl documentation for B::Terse.
Here is our local, out-dated (pre-5.6) version:
B::Terse - Walk Perl syntax tree, printing terse info about ops
perl -MO=Terse[,OPTIONS] foo.pl
See ext/B/README.
AUTHOR
Malcolm Beattie, mbeattie@sable.ox.ac.uk