https://gcc.gnu.org/bugzilla/show_bug.cgi?id=53652
--- Comment #5 from Segher Boessenkool <segher at gcc dot gnu.org> --- It might work a lot better if it didn't have to load that all-ones vector in a separate insn. Because it does, you need to do a 3->3 combination (which we do not currently support) if you need to do the memory load in a separate insn, as well the the insn needed to keep the constant load (it isn't dead yet, later insns use that same value again)). So that would mean having insns (that split) for doing a NOT.
