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// run-pass
#![allow(unused_must_use)]
// ignore-emscripten FIXME(#45351) hits an LLVM assert
#![feature(repr_simd, platform_intrinsics, concat_idents, test)]
#![allow(non_camel_case_types)]
extern crate test;
#[repr(simd)]
#[derive(PartialEq, Debug)]
struct i32x4(i32, i32, i32, i32);
#[repr(simd)]
#[derive(PartialEq, Debug)]
struct i8x4(i8, i8, i8, i8);
#[repr(simd)]
#[derive(PartialEq, Debug)]
struct u32x4(u32, u32, u32, u32);
#[repr(simd)]
#[derive(PartialEq, Debug)]
struct u8x4(u8, u8, u8, u8);
#[repr(simd)]
#[derive(PartialEq, Debug)]
struct f32x4(f32, f32, f32, f32);
#[repr(simd)]
#[derive(PartialEq, Debug)]
struct f64x4(f64, f64, f64, f64);
extern "platform-intrinsic" {
fn simd_cast<T, U>(x: T) -> U;
}
const A: i32 = -1234567;
const B: i32 = 12345678;
const C: i32 = -123456789;
const D: i32 = 1234567890;
trait Foo {
fn is_float() -> bool { false }
fn in_range(x: i32) -> bool;
}
impl Foo for i32 {
fn in_range(_: i32) -> bool { true }
}
impl Foo for i8 {
fn in_range(x: i32) -> bool { -128 <= x && x < 128 }
}
impl Foo for u32 {
fn in_range(x: i32) -> bool { 0 <= x }
}
impl Foo for u8 {
fn in_range(x: i32) -> bool { 0 <= x && x < 128 }
}
impl Foo for f32 {
fn is_float() -> bool { true }
fn in_range(_: i32) -> bool { true }
}
impl Foo for f64 {
fn is_float() -> bool { true }
fn in_range(_: i32) -> bool { true }
}
fn main() {
macro_rules! test {
($from: ident, $to: ident) => {{
// force the casts to actually happen, or else LLVM/rustc
// may fold them and get slightly different results.
let (a, b, c, d) = test::black_box((A as $from, B as $from, C as $from, D as $from));
// the SIMD vectors are all FOOx4, so we can concat_idents
// so we don't have to pass in the extra args to the macro
let mut from = simd_cast(concat_idents!($from, x4)(a, b, c, d));
let mut to = concat_idents!($to, x4)(a as $to,
b as $to,
c as $to,
d as $to);
// assist type inference, it needs to know what `from` is
// for the `if` statements.
to == from;
// there are platform differences for some out of range
// casts, so we just normalize such things: it's OK for
// "invalid" calculations to result in nonsense answers.
// (e.g., negative float to unsigned integer goes through a
// library routine on the default i686 platforms, and the
// implementation of that routine differs on e.g., Linux
// vs. macOS, resulting in different answers.)
if $from::is_float() {
if !$to::in_range(A) { from.0 = 0 as $to; to.0 = 0 as $to; }
if !$to::in_range(B) { from.1 = 0 as $to; to.1 = 0 as $to; }
if !$to::in_range(C) { from.2 = 0 as $to; to.2 = 0 as $to; }
if !$to::in_range(D) { from.3 = 0 as $to; to.3 = 0 as $to; }
}
assert!(to == from,
"{} -> {} ({:?} != {:?})", stringify!($from), stringify!($to),
from, to);
}}
}
macro_rules! tests {
(: $($to: ident),*) => { () };
// repeating the list twice is easier than writing a cartesian
// product macro
($from: ident $(, $from_: ident)*: $($to: ident),*) => {
fn $from() { unsafe { $( test!($from, $to); )* } }
tests!($($from_),*: $($to),*)
};
($($types: ident),*) => {{
tests!($($types),* : $($types),*);
$($types();)*
}}
}
// test various combinations, including truncation,
// signed/unsigned extension, and floating point casts.
tests!(i32, i8, u32, u8, f32);
tests!(i32, u32, f32, f64)
}
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