[Bug tree-optimization/78103] Failure to optimize with __builtin_clzl

[ben.maurer at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=78103

--- Comment #1 from Ben Maurer <ben.maurer at gmail dot com> ---
Also along the same lines:

https://godbolt.org/g/Nzed5m

GCC figures out BSRNew, but there's a cdqe instruction that's unnecessary