TracePoint line coverage


I'm playing around with TracePoint API and code coverage using :line event.

I'd like to be able to generate a percentage coverage report for a given
file. While I can easily see what lines are executed, I can't easily
determine what lines are not executed.

What I need, I think, is a tracepoint which triggers for eval/load/require,
which allows me to determine the initial coverage of the file. In addition,
what I need in the case of eval is the actual code, or even more
preferably, the instruction sequence and a means by which I can extract the
initial coverage.

Any thoughts?