I was browsing the language shootout the other day and came across the page for the regex test. I'm not sure how it's doing it or if something is wrong with the test but V8 is outperforming everything else, including C. That's the only test it leads though.
V8 JIT-compiles regular expressions. I don't know what C/C++ do -- I'd assume they run the state machine directly, but maybe they do compile it further like V8 does.
http://blog.chromium.org/2009/02/irregexp-google-chromes-new...