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//@[old]run-pass
//@[generic_with_fn]run-pass
//@ revisions: old generic generic_with_fn
#![feature(repr_simd, intrinsics, adt_const_params, unsized_const_params, generic_const_exprs)]
#![allow(incomplete_features)]
extern "rust-intrinsic" {
#[cfg(old)]
fn simd_shuffle<T, I, U>(a: T, b: T, i: I) -> U;
#[cfg(any(generic, generic_with_fn))]
fn simd_shuffle_generic<T, U, const I: &'static [u32]>(a: T, b: T) -> U;
}
#[derive(Copy, Clone)]
#[repr(simd)]
struct Simd<T, const N: usize>([T; N]);
trait Shuffle<const N: usize> {
const I: Simd<u32, N>;
const J: &'static [u32] = &Self::I.0;
unsafe fn shuffle<T, const M: usize>(&self, a: Simd<T, M>, b: Simd<T, M>) -> Simd<T, N>
where
Thing<{ Self::J }>:,
{
#[cfg(old)]
return simd_shuffle(a, b, Self::I);
#[cfg(generic)]
return simd_shuffle_generic::<_, _, { &Self::I.0 }>(a, b);
//[generic]~^ overly complex generic constant
#[cfg(generic_with_fn)]
return simd_shuffle_generic::<_, _, { Self::J }>(a, b);
}
}
struct Thing<const X: &'static [u32]>;
fn main() {
struct I1;
impl Shuffle<4> for I1 {
const I: Simd<u32, 4> = Simd([0, 2, 4, 6]);
}
struct I2;
impl Shuffle<2> for I2 {
const I: Simd<u32, 2> = Simd([1, 5]);
}
let a = Simd::<u8, 4>([0, 1, 2, 3]);
let b = Simd::<u8, 4>([4, 5, 6, 7]);
unsafe {
let x: Simd<u8, 4> = I1.shuffle(a, b);
assert_eq!(x.0, [0, 2, 4, 6]);
let y: Simd<u8, 2> = I2.shuffle(a, b);
assert_eq!(y.0, [1, 5]);
}
}
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