rust/tests/ui/simd/dont-invalid-bitcast-x86_64.rs
2024-06-24 16:54:18 -07:00

28 lines
1.0 KiB
Rust

//@ build-pass
//@ compile-flags: -Copt-level=3
//@ only-x86_64
// ignore-tidy-linelength
// regression test for https://github.com/rust-lang/rust/issues/110707
// in --release we were optimizing to invalid bitcasts, due to a combination of MIR inlining and
// mostly bad repr(simd) lowering which prevented even basic splats from working
#![crate_type = "rlib"]
#![feature(portable_simd)]
use std::simd::*;
use std::arch::x86_64::*;
#[target_feature(enable = "sse4.1")]
pub unsafe fn fast_round_sse(i: f32x8) -> f32x8 {
let a = i.to_array();
let [low, high]: [[f32; 4]; 2] =
unsafe { std::mem::transmute::<[f32; 8], [[f32; 4]; 2]>(a) };
let low = f32x4::from(_mm_round_ps::<{_MM_FROUND_TO_NEAREST_INT | _MM_FROUND_NO_EXC}>(f32x4::from_array(low).into()));
let high = f32x4::from(_mm_round_ps::<{_MM_FROUND_TO_NEAREST_INT | _MM_FROUND_NO_EXC}>(f32x4::from_array(high).into()));
let a: [f32; 8] =
unsafe { std::mem::transmute::<[[f32; 4]; 2], [f32; 8]>([low.to_array(), high.to_array()]) };
f32x8::from_array(a)
}