[Bug rtl-optimization/89435] [7/8/9 Regression] wrong code with -O1 -march=armv4 -fno-forward-propagate with __builtin_sub_overflow()

[jakub at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=89435

--- Comment #6 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
And sure, if you could look at this (or somebody from ARM otherwise), it would
be highly appreciated.