[Bug target/117008] -march=native pessimization of 25% with bitset []

[redi at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=117008

--- Comment #7 from Jonathan Wakely <redi at gcc dot gnu.org> ---
(In reply to Matt Bentley from comment #4)
> I haven't tested whether vector/array
> indexing triggers the same bad vectorisation.

I'm certain it won't be, because (apart from vector<bool>) they access memory
locations that are at least one byte, not repeating very similar bitwise ops
for every bit in a word.