std::intrinsics

Function ctlz_nonzero

const: 1.50.0 · source 
pub const unsafe extern "rust-intrinsic" fn ctlz_nonzero<T>(
    x: T,
) -> u32
where
    T: Copy,
🔬This is a nightly-only experimental API. (core_intrinsics)
Expand description

Like ctlz, but extra-unsafe as it returns undef when given an x with value 0.

This intrinsic does not have a stable counterpart.

§Examples

#![feature(core_intrinsics)]

use std::intrinsics::ctlz_nonzero;

let x = 0b0001_1100_u8;
let num_leading = unsafe { ctlz_nonzero(x) };
assert_eq!(num_leading, 3);