diff options
| -rw-r--r-- | src/libcore/intrinsics.rs | 52 |
1 files changed, 50 insertions, 2 deletions
diff --git a/src/libcore/intrinsics.rs b/src/libcore/intrinsics.rs index 3726eee9a93..31a0cc68841 100644 --- a/src/libcore/intrinsics.rs +++ b/src/libcore/intrinsics.rs @@ -1156,10 +1156,58 @@ extern "rust-intrinsic" { /// Returns the number of bits set in an integer type `T` pub fn ctpop<T>(x: T) -> T; - /// Returns the number of leading bits unset in an integer type `T` + /// Returns the number of leading unset bits (zeroes) in an integer type `T`. + /// + /// # Examples + /// + /// ``` + /// #![feature(core_intrinsics)] + /// + /// use std::intrinsics::ctlz; + /// + /// let x = 0b0001_1100_u8; + /// let num_leading = unsafe { ctlz(x) }; + /// assert_eq!(num_leading, 3); + /// ``` + /// + /// An `x` with value `0` will return the bit width of `T`. + /// + /// ``` + /// #![feature(core_intrinsics)] + /// + /// use std::intrinsics::ctlz; + /// + /// let x = 0u16; + /// let num_leading = unsafe { ctlz(x) }; + /// assert_eq!(num_leading, 16); + /// ``` pub fn ctlz<T>(x: T) -> T; - /// Returns the number of trailing bits unset in an integer type `T` + /// Returns the number of trailing unset bits (zeroes) in an integer type `T`. + /// + /// # Examples + /// + /// ``` + /// #![feature(core_intrinsics)] + /// + /// use std::intrinsics::cttz; + /// + /// let x = 0b0011_1000_u8; + /// let num_trailing = unsafe { cttz(x) }; + /// assert_eq!(num_trailing, 3); + /// ``` + /// + /// An `x` with value `0` will return the bit width of `T`: + /// + /// ``` + /// #![feature(core_intrinsics)] + /// + /// use std::intrinsics::cttz; + /// + /// let x = 0u16; + /// let num_trailing = unsafe { cttz(x) }; + /// assert_eq!(num_trailing, 16); + /// ``` pub fn cttz<T>(x: T) -> T; /// Reverses the bytes in an integer type `T`. |