lower

Crates.iolower
lib.rslower
version0.2.0
sourcesrc
created_at2024-02-17 01:18:49.601244
updated_at2025-02-03 08:05:19.76849
descriptiondesugar math where the compiler wont
homepage
repositoryhttps://github.com/bend-n/lower-plus.git
max_upload_size
id1142927
size5,538
bendn (bend-n)

documentation

README

lower

lowers expressions to their "desugared" form.

e.g

a * b + c => (a.mul(b)).add(c)

note that it is extremely pervasive, so

lower::math! { fn main() -> u8 {
    const X: u8 = 31 * 2;
    return 2 * X + 2;
} }

expands to

fn main() -> u8 {
    const X: u8 = 31.mul(2);
    return (2.mul(X)).add(2);
}

it should work for most expressions.

also implements some modules that let it work with some core intrinsics (f*_fast, f*_algebraic). (nightly only!)

why

rust added an amazing feature called algebraic math (thanks orlp), allowing us to use f*_algebraic. however, dont you hate it when your

fn madd<const N: usize>(x: [[f32; 3]; N]) -> [f32; N] {
    x.map(|[a, b, c]| a * b + c) // not optimized! cant use `(v)fmadd`
}

turns into

fn madd<const N: usize>(x: [[f32; 3]; N]) -> [f32; N] {
    x.map(|[a, b, c]| core::intrinsics::fadd_algebraic(core::intrinsics::fmul_algebraic(a, b), c)) // readability in shambles
}

this crate allows you to

fn madd<const N: usize>(x: [[f32; 3]; N]) -> [f32; N] {
    // wow! such readability! ultimate simd!
    lower::algebraic! { x.map(|[a, b, c]| a * b + c) }
}
Commit count: 3

cargo fmt