27 lines
815 B
Rust
27 lines
815 B
Rust
|
// build-pass
|
||
|
|
#![crate_type = "lib"]
|
||
|
|
#![allow(arithmetic_overflow)]
|
||
|
|
|
||
|
|
pub trait BitSplit {
|
||
|
|
type Half;
|
||
|
|
fn merge(halves: [Self::Half; 2]) -> Self;
|
||
|
|
}
|
||
|
|
|
||
|
|
macro_rules! impl_ints {
|
||
|
|
($int:ty => $half:ty; $mask:expr) => {
|
||
|
|
impl BitSplit for $int {
|
||
|
|
type Half = $half;
|
||
|
|
#[inline]
|
||
|
|
fn merge(halves: [Self::Half; 2]) -> Self {
|
||
|
|
const HALF_SIZE: usize = std::mem::size_of::<$half>() * 8;
|
||
|
|
(halves[0] << HALF_SIZE) as $int | halves[1] as $int
|
||
|
|
}
|
||
|
|
}
|
||
|
|
};
|
||
|
|
}
|
||
|
|
|
||
|
|
impl_ints!(u128 => u64; 0x0000_0000_0000_0000_FFFF_FFFF_FFFF_FFFF);
|
||
|
|
impl_ints!( u64 => u32; 0x0000_0000_FFFF_FFFF);
|
||
|
|
impl_ints!( u32 => u16; 0x0000_FFFF);
|
||
|
|
impl_ints!( u16 => u8; 0x00FF);
|