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// SPDX-License-Identifier: GPL-2.0 //! Pre-defined atomic types use crate::static_assert;use core::mem::{align_of, size_of}; // SAFETY: `i32` has the same size and alignment with itself, and is round-trip transmutable to// itself.unsafe impl super::AtomicType for i32 {    type Repr = i32;} // SAFETY: The wrapping add result of two `i32`s is a valid `i32`.unsafe impl super::AtomicAdd<i32> for i32 {    fn rhs_into_delta(rhs: i32) -> i32 {        rhs    }} // SAFETY: `i64` has the same size and alignment with itself, and is round-trip transmutable to// itself.unsafe impl super::AtomicType for i64 {    type Repr = i64;} // SAFETY: The wrapping add result of two `i64`s is a valid `i64`.unsafe impl super::AtomicAdd<i64> for i64 {    fn rhs_into_delta(rhs: i64) -> i64 {        rhs    }} // Defines an internal type that always maps to the integer type which has the same size alignment// as `isize` and `usize`, and `isize` and `usize` are always bi-directional transmutable to// `isize_atomic_repr`, which also always implements `AtomicImpl`.#[allow(non_camel_case_types)]#[cfg(not(CONFIG_64BIT))]type isize_atomic_repr = i32;#[allow(non_camel_case_types)]#[cfg(CONFIG_64BIT)]type isize_atomic_repr = i64; // Ensure size and alignment requirements are checked.static_assert!(size_of::<isize>() == size_of::<isize_atomic_repr>());static_assert!(align_of::<isize>() == align_of::<isize_atomic_repr>());static_assert!(size_of::<usize>() == size_of::<isize_atomic_repr>());static_assert!(align_of::<usize>() == align_of::<isize_atomic_repr>()); // SAFETY: `isize` has the same size and alignment with `isize_atomic_repr`, and is round-trip// transmutable to `isize_atomic_repr`.unsafe impl super::AtomicType for isize {    type Repr = isize_atomic_repr;} // SAFETY: The wrapping add result of two `isize_atomic_repr`s is a valid `usize`.unsafe impl super::AtomicAdd<isize> for isize {    fn rhs_into_delta(rhs: isize) -> isize_atomic_repr {        rhs as isize_atomic_repr    }} // SAFETY: `u32` and `i32` has the same size and alignment, and `u32` is round-trip transmutable to// `i32`.unsafe impl super::AtomicType for u32 {    type Repr = i32;} // SAFETY: The wrapping add result of two `i32`s is a valid `u32`.unsafe impl super::AtomicAdd<u32> for u32 {    fn rhs_into_delta(rhs: u32) -> i32 {        rhs as i32    }} // SAFETY: `u64` and `i64` has the same size and alignment, and `u64` is round-trip transmutable to// `i64`.unsafe impl super::AtomicType for u64 {    type Repr = i64;} // SAFETY: The wrapping add result of two `i64`s is a valid `u64`.unsafe impl super::AtomicAdd<u64> for u64 {    fn rhs_into_delta(rhs: u64) -> i64 {        rhs as i64    }} // SAFETY: `usize` has the same size and alignment with `isize_atomic_repr`, and is round-trip// transmutable to `isize_atomic_repr`.unsafe impl super::AtomicType for usize {    type Repr = isize_atomic_repr;} // SAFETY: The wrapping add result of two `isize_atomic_repr`s is a valid `usize`.unsafe impl super::AtomicAdd<usize> for usize {    fn rhs_into_delta(rhs: usize) -> isize_atomic_repr {        rhs as isize_atomic_repr    }} use crate::macros::kunit_tests; #[kunit_tests(rust_atomics)]mod tests {    use super::super::*;     // Call $fn($val) with each $type of $val.    macro_rules! for_each_type {        ($val:literal in [$($type:ty),*] $fn:expr) => {            $({                let v: $type = $val;                 $fn(v);            })*        }    }     #[test]    fn atomic_basic_tests() {        for_each_type!(42 in [i32, i64, u32, u64, isize, usize] |v| {            let x = Atomic::new(v);             assert_eq!(v, x.load(Relaxed));        });    }     #[test]    fn atomic_xchg_tests() {        for_each_type!(42 in [i32, i64, u32, u64, isize, usize] |v| {            let x = Atomic::new(v);             let old = v;            let new = v + 1;             assert_eq!(old, x.xchg(new, Full));            assert_eq!(new, x.load(Relaxed));        });    }     #[test]    fn atomic_cmpxchg_tests() {        for_each_type!(42 in [i32, i64, u32, u64, isize, usize] |v| {            let x = Atomic::new(v);             let old = v;            let new = v + 1;             assert_eq!(Err(old), x.cmpxchg(new, new, Full));            assert_eq!(old, x.load(Relaxed));            assert_eq!(Ok(old), x.cmpxchg(old, new, Relaxed));            assert_eq!(new, x.load(Relaxed));        });    }     #[test]    fn atomic_arithmetic_tests() {        for_each_type!(42 in [i32, i64, u32, u64, isize, usize] |v| {            let x = Atomic::new(v);             assert_eq!(v, x.fetch_add(12, Full));            assert_eq!(v + 12, x.load(Relaxed));             x.add(13, Relaxed);             assert_eq!(v + 25, x.load(Relaxed));        });    }}