big o - Are there any tools that can determine perform code analysis for Big-O complexity?

Question

I haven't seen anything out there, and I suspect the difficulty with defining "n" since for generally for analyzing a complex function there'd be more than just one or two variables for defining.

There are analysis tools for cyclomatic complexity but are there ones for time (and/or space) complexity? If so which ones, if not, why not? Is it infeasible? Impossible? Someone just hasn't gotten around to it?

Ideally there'd be something like overall complexity for the application (defining different possible "n"s) as well as for each method in the app

Edit: So it seems like an exact solution is impossible because of the Halting Problem however, is some kind of heuristic approximation possible? I realize that for practical purposes a good profiler will give much more useful information, but it seems like an interesting problem.

Also, how about one that calculates for a certain subset of programs?

Answer 1

Unfortunately there is this problem called the Halting problem...