[Bug tree-optimization/104376] Failure to optimize clz equivalent to clz

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

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=104376

--- Comment #2 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
The second issue can be seen with:
#include <stdint.h>

uint32_t countLeadingZeros32(uint32_t x)
{
    if (x == 0)
        return 32;
    return (__builtin_clz(x)) ;
}

This gets optimized for aarch64 at the rtl level but not for x86_64 with
-mlzcnt.