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//@ run-pass
#![feature(repr_simd, intrinsics)]
#![allow(non_camel_case_types)]
#[repr(simd, packed)]
struct Simd<T, const N: usize>([T; N]);
fn check_size_align<T, const N: usize>() {
use std::mem;
assert_eq!(mem::size_of::<Simd<T, N>>(), mem::size_of::<[T; N]>());
assert_eq!(mem::size_of::<Simd<T, N>>() % mem::align_of::<Simd<T, N>>(), 0);
}
fn check_ty<T>() {
check_size_align::<T, 1>();
check_size_align::<T, 2>();
check_size_align::<T, 3>();
check_size_align::<T, 4>();
check_size_align::<T, 8>();
check_size_align::<T, 9>();
check_size_align::<T, 15>();
}
extern "rust-intrinsic" {
fn simd_add<T>(a: T, b: T) -> T;
}
fn main() {
check_ty::<u8>();
check_ty::<i16>();
check_ty::<u32>();
check_ty::<i64>();
check_ty::<usize>();
check_ty::<f32>();
check_ty::<f64>();
unsafe {
// powers-of-two have no padding and have the same layout as #[repr(simd)]
let x: Simd<f64, 4> =
simd_add(Simd::<f64, 4>([0., 1., 2., 3.]), Simd::<f64, 4>([2., 2., 2., 2.]));
assert_eq!(std::mem::transmute::<_, [f64; 4]>(x), [2., 3., 4., 5.]);
// non-powers-of-two should have padding (which is removed by #[repr(packed)]),
// but the intrinsic handles it
let x: Simd<f64, 3> = simd_add(Simd::<f64, 3>([0., 1., 2.]), Simd::<f64, 3>([2., 2., 2.]));
let arr: [f64; 3] = x.0;
assert_eq!(arr, [2., 3., 4.]);
}
}
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