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//@ run-pass
//@ ignore-emscripten
// Test that the simd_{gather,scatter} intrinsics produce the correct results.
#![feature(repr_simd, intrinsics)]
#![allow(non_camel_case_types)]
#[repr(simd)]
#[derive(Copy, Clone, PartialEq, Debug)]
struct x4<T>(pub [T; 4]);
extern "rust-intrinsic" {
fn simd_gather<T, U, V>(x: T, y: U, z: V) -> T;
fn simd_scatter<T, U, V>(x: T, y: U, z: V) -> ();
}
fn main() {
let mut x = [0_f32, 1., 2., 3., 4., 5., 6., 7.];
let default = x4([-3_f32, -3., -3., -3.]);
let s_strided = x4([0_f32, 2., -3., 6.]);
let mask = x4([-1_i32, -1, 0, -1]);
// reading from *const
unsafe {
let pointer = x.as_ptr();
let pointers = x4([
pointer.offset(0),
pointer.offset(2),
pointer.offset(4),
pointer.offset(6)
]);
let r_strided = simd_gather(default, pointers, mask);
assert_eq!(r_strided, s_strided);
}
// reading from *mut
unsafe {
let pointer = x.as_mut_ptr();
let pointers = x4([
pointer.offset(0),
pointer.offset(2),
pointer.offset(4),
pointer.offset(6)
]);
let r_strided = simd_gather(default, pointers, mask);
assert_eq!(r_strided, s_strided);
}
// writing to *mut
unsafe {
let pointer = x.as_mut_ptr();
let pointers = x4([
pointer.offset(0),
pointer.offset(2),
pointer.offset(4),
pointer.offset(6)
]);
let values = x4([42_f32, 43_f32, 44_f32, 45_f32]);
simd_scatter(values, pointers, mask);
assert_eq!(x, [42., 1., 43., 3., 4., 5., 45., 7.]);
}
// test modifying array of *const f32
let mut y = [
&x[0] as *const f32,
&x[1] as *const f32,
&x[2] as *const f32,
&x[3] as *const f32,
&x[4] as *const f32,
&x[5] as *const f32,
&x[6] as *const f32,
&x[7] as *const f32
];
let default = x4([y[0], y[0], y[0], y[0]]);
let s_strided = x4([y[0], y[2], y[0], y[6]]);
// reading from *const
unsafe {
let pointer = y.as_ptr();
let pointers = x4([
pointer.offset(0),
pointer.offset(2),
pointer.offset(4),
pointer.offset(6)
]);
let r_strided = simd_gather(default, pointers, mask);
assert_eq!(r_strided, s_strided);
}
// reading from *mut
unsafe {
let pointer = y.as_mut_ptr();
let pointers = x4([
pointer.offset(0),
pointer.offset(2),
pointer.offset(4),
pointer.offset(6)
]);
let r_strided = simd_gather(default, pointers, mask);
assert_eq!(r_strided, s_strided);
}
// writing to *mut
unsafe {
let pointer = y.as_mut_ptr();
let pointers = x4([
pointer.offset(0),
pointer.offset(2),
pointer.offset(4),
pointer.offset(6)
]);
let values = x4([y[7], y[6], y[5], y[1]]);
simd_scatter(values, pointers, mask);
let s = [
&x[7] as *const f32,
&x[1] as *const f32,
&x[6] as *const f32,
&x[3] as *const f32,
&x[4] as *const f32,
&x[5] as *const f32,
&x[1] as *const f32,
&x[7] as *const f32
];
assert_eq!(y, s);
}
}
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