-//! Provides the fast math trait and macro. See terms and conditions[^1].

-//!

-//! [^1]: <https://simonbyrne.github.io/notes/fastmath>

-#[allow(unused_imports)]

-use std::f32::{INFINITY as INF, NAN};

-

-macro_rules! s {

- ($($x:tt)+) => {

- #[doc = include_str!("fast.safety.md")]

- $($x)+;

- };

-}

-

-#[rustfmt::skip]

-/// Trait for fast math floats. Try to use [`fast::math`](crate::fast::math).

-/// These functions all assume that your float is NOT [`INF`] | [`NAN`].

-/// If so undefined behaviour is incurred.

-pub unsafe trait Float: Copy {

- s!(unsafe fn add(self, other: Self) -> Self);

- s!(unsafe fn sub(self, other: Self) -> Self);

- s!(unsafe fn mul(self, other: Self) -> Self);

- s!(unsafe fn div(self, other: Self) -> Self);

- s!(unsafe fn rem(self, other: Self) -> Self);

-

- s!(unsafe fn eq(self, other: Self) -> bool);

- s!(unsafe fn lt(self, other: Self) -> bool);

- s!(unsafe fn le(self, other: Self) -> bool);

- s!(unsafe fn ne(self, other: Self) -> bool);

- s!(unsafe fn ge(self, other: Self) -> bool);

- s!(unsafe fn gt(self, other: Self) -> bool);

-

- fn deref(&self) -> Self {

- *self

- }

- fn neg(self) -> Self;

-

- #[doc(hidden)]

- unsafe fn finite(self, other: Self) -> Self;

-}

-

-use std::intrinsics::*;

-macro_rules! imp {

- ($this:ty) => {

-#[rustfmt::skip]

-unsafe impl Float for $this {

- #[inline(always)]

- unsafe fn finite(self, other: Self) -> Self {

- core::hint::assert_unchecked(self.is_finite());

- core::hint::assert_unchecked(other.is_finite());

- self

- }

- unsafe fn add(self, other: Self) -> Self { fadd_fast(self.finite(other), other) }

- unsafe fn sub(self, other: Self) -> Self { fsub_fast(self.finite(other), other) }

- unsafe fn mul(self, other: Self) -> Self { fmul_fast(self.finite(other), other) }

- unsafe fn div(self, other: Self) -> Self { fdiv_fast(self.finite(other), other) }

- unsafe fn rem(self, other: Self) -> Self { frem_fast(self.finite(other), other) }

-

- unsafe fn eq(self, other: Self) -> bool { (self.finite(other) + 0.0).to_bits() == (other + 0.0).to_bits() }

- unsafe fn lt(self, other: Self) -> bool { self.finite(other) < other }

- unsafe fn le(self, other: Self) -> bool { self.finite(other) <= other }

- unsafe fn ne(self, other: Self) -> bool { self.finite(other) != other }

- unsafe fn ge(self, other: Self) -> bool { self.finite(other) >= other }

- unsafe fn gt(self, other: Self) -> bool { self.finite(other) > other }

-

- fn deref(&self) -> Self { *self }

- fn neg(self) -> Self { -self }

-}

- };

-}

-imp!(f32);

-imp!(f64);

-

-/// Changes all the math to fast float math. See [`fadd_fast`].

-///

-/// This allows automatic vectorization of float math for the compiler, among other things.

-/// If you intend to create a function in this, first import [`lower::fast::Float`](crate::fast::Float), use [`lower::math`](crate::math).

-///

-/// This would lower `a * b + c` to `fadd(fmul(a, b), c)`.

-#[macro_export]

-#[doc(hidden)]

-macro_rules! fast {

- ($($x:tt)+) => {{

- use $crate::fast::Float as _;

- lower_macros::math! { $($x)+ }

- }}

-}

-#[doc(inline)]

-pub use fast as math;