kernel/
num.rs

1// SPDX-License-Identifier: GPL-2.0
2
3//! Additional numerical features for the kernel.
4
5use core::ops;
6
7pub mod bounded;
8pub use bounded::*;
9
10/// Designates unsigned primitive types.
11pub enum Unsigned {}
12
13/// Designates signed primitive types.
14pub enum Signed {}
15
16/// Describes core properties of integer types.
17pub trait Integer:
18    Sized
19    + Copy
20    + Clone
21    + PartialEq
22    + Eq
23    + PartialOrd
24    + Ord
25    + ops::Add<Output = Self>
26    + ops::AddAssign
27    + ops::Sub<Output = Self>
28    + ops::SubAssign
29    + ops::Mul<Output = Self>
30    + ops::MulAssign
31    + ops::Div<Output = Self>
32    + ops::DivAssign
33    + ops::Rem<Output = Self>
34    + ops::RemAssign
35    + ops::BitAnd<Output = Self>
36    + ops::BitAndAssign
37    + ops::BitOr<Output = Self>
38    + ops::BitOrAssign
39    + ops::BitXor<Output = Self>
40    + ops::BitXorAssign
41    + ops::Shl<u32, Output = Self>
42    + ops::ShlAssign<u32>
43    + ops::Shr<u32, Output = Self>
44    + ops::ShrAssign<u32>
45    + ops::Not
46{
47    /// Whether this type is [`Signed`] or [`Unsigned`].
48    type Signedness;
49
50    /// Number of bits used for value representation.
51    const BITS: u32;
52}
53
54macro_rules! impl_integer {
55    ($($type:ty: $signedness:ty), *) => {
56        $(
57        impl Integer for $type {
58            type Signedness = $signedness;
59
60            const BITS: u32 = <$type>::BITS;
61        }
62        )*
63    };
64}
65
66impl_integer!(
67    u8: Unsigned,
68    u16: Unsigned,
69    u32: Unsigned,
70    u64: Unsigned,
71    u128: Unsigned,
72    usize: Unsigned,
73    i8: Signed,
74    i16: Signed,
75    i32: Signed,
76    i64: Signed,
77    i128: Signed,
78    isize: Signed
79);