[Bug rtl-optimization/90249] [9/10 Regression] Code size regression on thumb2 due to sub-optimal register allocation starting with r265398

[segher at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=90249

--- Comment #4 from Segher Boessenkool <segher at gcc dot gnu.org> ---
That is code *size*.  Code size is expected to grow a tiny bit, because of
*better* register allocation.

But we could not do make_more_copies at -Os, if that helps?  (The hard register
changes themselves are required for correctness).