Changes to ghc(3)

Changes to ghc:
commit b26e2f92c5c6f77fe361293a128da637e728959c
Author: Joachim Breitner <mail@joachim-breitner.de>
Date:   Thu Jan 16 16:55:07 2014 +0000

    Remove unused returnsCPR

commit 7cdf141d7234992466f0ce790e6659c859568783
Author: Joachim Breitner <mail@joachim-breitner.de>
Date:   Thu Jan 16 14:42:31 2014 +0000

    Refactor WorkWrap, get rid of worthSplittingArgDmd

    Instead of first checking whether splitting is useful, and then firing
    up the worker-wrapper-machinery, which will do the same checks again, we
    now simply generate a worker and wrapper, and while doing so keep track
    of whether what we did was in any way useful.

    So now there is only one place left where we decide whether we want to
    do w/w, and that place has access to more information, in particular the
    actual types at hand.

commit ab74d75d029cdbbb9215b48f1611259fe4d7dd19
Author: Joachim Breitner <mail@joachim-breitner.de>
Date:   Thu Jan 16 13:59:31 2014 +0000

    Replace worthSplittingThunkDmd by worthSplittingArgDmd

    these functions were almost equal, and neither validate nor nofib show
    any difference replacing one by the other. So lets simplify this.
    (This also prepares for a refactoring that will get rid of
    worthSplittingArgDmd completely.)