`breadsimd`

breadsimd is a library for SIMD (Single Instruction Multiple Data) operations on arrays of number values. The main idea with breadsimd is that, in Rust, it should be possible to have your cake and eat it, too. Types in breadsimd are generic over the type, meaning that they can contain any number value. However, using specialization, breadsimd can also provide optimized implementations for specific types, such as f32 and i64.

If the unstable-exclusive nightly feature is enabled, the crate enables SIMD optimizations, through the currently-unstable portable-simd and specialization features. If not, it falls back to a naive implementation.

Usage

use breadsimd::Double;
use core::num::Wrapping;

// At the time of writing, `Wrapping<u32>` is not optimized using SIMD.
let mut a = Double::new([Wrapping(1), Wrapping(2)]);
a += Double::new([Wrapping(3), Wrapping(4)]);
assert_eq!(a, Double::new([Wrapping(4), Wrapping(6)]));

// However, `u32` is optimized using SIMD.
let mut b = Double::<u32>::new([1, 2]);
b += Double::new([3, 4]);
assert_eq!(b, Double::new([4, 6]));

Features

std (enabled by default) - Enables the usage of libstd within breadsimd. This does not affect the external API, but implements sqrt in a more efficient way.
nightly (requires a nightly compiler) - Enables certain generic types to be replaced with SIMD primitives. This is currently only supported on nightly, as it requires the portable-simd and specialization features.
bytemuck - Implements bytemuck::Pod and bytemuck::Zeroable for Double and Quad.

Dependency Justification

Legend: Italics indicate an optional dependency, while bold indicates a public dependency.

bytemuck (version 1.12 or later) - Provides Pod and Zeroable implementations for Double and Quad. This is only enabled when the bytemuck feature is enabled.
cfg-if (version 1.0 or later) - Provides cfg_if! macro, which is used to conditionally compile code based on the nightly feature.
num-traits (version 0.2 or later) - Provides numerical traits like Real or Signed, which provide for generic functionality over number types.

Future Plans

This crate will not release its 1.0.0 version until the specialization and portable_simd features in the standard library are stable.

License

This crate is dual licensed under the Boost Software License (LICENSE-BOOST) and the Apache 2.0 License (LICENSE-APACHE), at your option. See LICENSE-APACHE and LICENSE-BOOST for details.

Contributions

Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in the work by you, as defined in the Apache-2.0 license, shall be dual licensed as above, without any additional terms or conditions.

notgull/breadsimd