[Bug target/84481] [8/9/10/11 Regression] 429.mcf with -O2 regresses by ~6% and ~4%, depending on tuning, on Zen compared to GCC 7.2

[jamborm at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=84481

--- Comment #12 from Martin Jambor <jamborm at gcc dot gnu.org> ---
I can once again confirm the slowdown on a zen1-based machine (commit
6e1e0decc9e vs gcc 7.5) but it is not present on a zen2-based one.  I wonder
whether the bug should me marked as WONTFIX.