[Bug target/96854] [10 Regression] avx vectorizer breaks complex arithmetic

[already5chosen at yahoo dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=96854

--- Comment #4 from Michael_S <already5chosen at yahoo dot com> ---
Pay attention that it's not just AVX.
'-mavx2 -mfma -Ofast' generates different code, but at the end gives the same
wrong result.
Unfortunately, I have no AVX512 hardware to test, but wouldn't be surprised if
it's also broken in 10.2.