Ah sorry, I read your ivdep sentence and the second part of your post as independent, i.e,. that the compiler should be able to assume this (even without ivdep)

Ah sorry, I read your ivdep sentence and the second part of your post as independent, i.e,. that the compiler should be able to assume this (even without ivdep). I realize now you were saying "[With ivdep] and in this specific case, the compiler should be able to assume..." It makes sense now.