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#![feature(core_intrinsics, portable_simd)]
use std::intrinsics::simd::simd_relaxed_fma;
use std::intrinsics::{fmuladdf32, fmuladdf64};
use std::simd::prelude::*;
#[path = "../../utils/mod.rs"]
mod utils;
use utils::check_nondet;
fn main() {
check_nondet(|| {
let a = std::hint::black_box(0.1_f64);
let b = std::hint::black_box(0.2);
let c = std::hint::black_box(-a * b);
// It is unspecified whether the following operation is fused or not. The
// following evaluates to 0.0 if unfused, and nonzero (-1.66e-18) if fused.
let x = fmuladdf64(a, b, c);
x == 0.0
});
check_nondet(|| {
let a = std::hint::black_box(0.1_f32);
let b = std::hint::black_box(0.2);
let c = std::hint::black_box(-a * b);
// It is unspecified whether the following operation is fused or not. The
// following evaluates to 0.0 if unfused, and nonzero (-8.1956386e-10) if fused.
let x = fmuladdf32(a, b, c);
x == 0.0
});
check_nondet(|| {
let a = f32x4::splat(std::hint::black_box(0.1));
let b = f32x4::splat(std::hint::black_box(0.2));
let c = std::hint::black_box(-a * b);
let x = unsafe { simd_relaxed_fma(a, b, c) };
// Whether we fuse or not is a per-element decision, so sometimes these should be
// the same and sometimes not.
x[0] == x[1]
});
check_nondet(|| {
let a = f64x4::splat(std::hint::black_box(0.1));
let b = f64x4::splat(std::hint::black_box(0.2));
let c = std::hint::black_box(-a * b);
let x = unsafe { simd_relaxed_fma(a, b, c) };
// Whether we fuse or not is a per-element decision, so sometimes these should be
// the same and sometimes not.
x[0] == x[1]
});
}
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