[Bug rtl-optimization/84101] [7/8/9 Regression] -O3 and -ftree-vectorize trying too hard for function returning trivial pair-of-uint64_t-structure

[segher at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=84101

--- Comment #6 from Segher Boessenkool <segher at gcc dot gnu.org> ---
I think subreg should deal with this.  What do you mean "there aren't
any half of TImode subregs"?  insn 10 has it split at the start, and
insn 18 at the end wants it split, too.