[Bug rtl-optimization/91137] [7/8/9/10 Regression] Wrong code with -O3

[amker at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=91137

--- Comment #11 from bin cheng <amker at gcc dot gnu.org> ---
Hi, suppose this patch should be backported to 8/7 if no further issues.