https://gcc.gnu.org/bugzilla/show_bug.cgi?id=85406
--- Comment #6 from Allan Jensen <linux at carewolf dot com> --- Yeah, the a==255 was actually not a case I would expect the compiler to solve, which is why I changed the example to the a==0 case, which should be solveable using existing constant propagation. Note you can put both short-cuts in, though as it standards only gcc 7 and 8 can vectorize it with two conditions, so we cant use that in general code as we need it to be fast elsewhere too.