[Bug middle-end/62263] Good codegen for bitwise rotate requires code that is technically undefined behavior

[oneill+gccbugs at cs dot hmc.edu]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=62263

--- Comment #1 from M.E. O'Neill <oneill+gccbugs at cs dot hmc.edu> ---
Possibly this should have been filed as a tree-level bug?  Also, see
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=17886 which mostly is about issues
with wider types, but may also cover this bug.