[Bug target/85755] PowerPC Gcc's -mupdate produces inefficient code on power8/power9 machines

[segher at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=85755

--- Comment #2 from Segher Boessenkool <segher at gcc dot gnu.org> ---
That is, that GCC 8 did not do pre-increment, but it did no silliness
with float registers.