Within the Termination Competition, there is a category on Functional Programming where the object is to prove termination of Haskell functions automatically.
Currently, the Termination Problems Data Base contains 1676 functions from the Haskell Prelude, and AProVE shows termination of 1294 of them.
The semantics of "termination" (in the context of the competition) is discussed e.g. in http://lists.lri.fr/pipermail/termtools/2006-March/000179.html
The termination analyzer AProVE has a web front end http://aprove.informatik.rwth-aachen.de/eval/Haskell/