[Bug target/43892] PowerPC suboptimal "add with carry" optimization

[segher at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=43892

--- Comment #19 from Segher Boessenkool <segher at gcc dot gnu.org> ---
Current code:

add 3,3,4
subfc 4,4,3
subfe 9,9,9
subf 3,9,3

so we got rid of the useless register move.