[Bug rtl-optimization/74585] powerpc64: Very poor code generation for homogeneous vector aggregates passed in registers

[wschmidt at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=74585

--- Comment #8 from Bill Schmidt <wschmidt at gcc dot gnu.org> ---
FYI, adding -mcpu=power9 to the options makes it much easier to read the RTL,
as it gets rid of the extra vector swaps needed for POWER8.