https://gcc.gnu.org/bugzilla/show_bug.cgi?id=126099
--- Comment #1 from Richard Biener <rguenth at gcc dot gnu.org> --- At some point I thought the bst_map caching could be enhanced to return permute nodes from existing nodes - that would have included a lowpart. This does of course tie subgraphs together very early where we might drop one completely during analysis. Another point is to do this in vect_cse_slp_nodes, but that's also done before stmt and dependence analysis.
