[Bug tree-optimization/89134] A missing optimization opportunity for a simple branch in loop

[jiangning.liu at amperecomputing dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=89134

--- Comment #5 from Jiangning Liu <jiangning.liu at amperecomputing dot com> ---
The loop below should be treated as a finite loop,

for (iter = booktable.begin(); iter!=booktable.end(); ++iter) {
   ...
}

so there is a chance to optimize away the empty loop, in which do_something
doesn't exist at all.