[Bug target/80846] auto-vectorized AVX2 horizontal sum should narrow to 128b right away, to be more efficient for Ryzen and Intel

[peter at cordes dot ca]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=80846

--- Comment #22 from Peter Cordes <peter at cordes dot ca> ---
Forgot the Godbolt link with updated cmdline options:
https://godbolt.org/g/FCZAEj.