http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51033
--- Comment #2 from Marc Glisse <marc.glisse at normalesup dot org> 2011-11-08 17:13:39 UTC --- It's probably doable, but it sounds like you have to duplicate all the logic that is currently in the various backends (and some in the C front-end and the middle-end I guess). The shuffle function has a different implementation for all versions of all architectures that provide vectorization. I am not sure how good an idea it is to decide that all this logic has to be coded twice, once for the C vector extension and one for the C++ library, where the 2 codes would be extremely different. Or I probably didn't quite get what you meant. Would you mind giving a few more details on how one would go about implementing it?
