[Bug target/88494] [9 Regression] polyhedron 10% mdbx runtime regression

[vekumar at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=88494

--- Comment #8 from vekumar at gcc dot gnu.org ---
I tested mdbx before and after the revision Richard pointed out. 
On My Ryzen box there is ~4% regression. 

Although "vblenvps" is fast path instruction and can execute in pipe 0/1. It
competes with vcmpccsd, fma and muls instruction that are also executing on
pipe 0|1. Looks to me regression is due to added dependency and port pressure.  

We need to benchmark with large application like SPEC and then decide whether
we need to enable X86_TUNE_SCALAR_FLOAT_BLENDV tuning for Ryzen or not. On
BDVER4 there were no blendvps generated and no regression seen.