[Bug target/91635] wrong code at -O2 with __builtin_add_overflow() and shifts

[kito at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=91635

--- Comment #12 from Kito Cheng <kito at gcc dot gnu.org> ---
Hi Zdenek:

I can reproduce for all new 3 testcases, it seems like cause by same issue,
thanks you provide more testcase for that!