[Bug c/124838] __builtin_clzl(0) overoptimization even on targets with native lzcnt instruction

[rguenth at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=124838

--- Comment #1 from Richard Biener <rguenth at gcc dot gnu.org> ---
You can use __builtin_clzg (x, <arg>) where <arg> is the result when x is zero.