https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94801
--- Comment #5 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
In the source yes, but by the time the optimizer sees it on some targets x == 0
? 32 : __builtin_clz (x) could have been already optimized into just
__builtin_clz (x) depending on what the target macros say.
/* __builtin_c[lt]z* return [0, prec-1], except for
when the argument is 0, but that is undefined behavior.
On many targets where the CLZ RTL or optab value is defined
for 0 the value is prec, so include that in the range
by default. */
