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