Designing a SIMD Algorithm from Scratch (mcyoung.xyz)

Article summary

The article discusses the design of a SIMD algorithm from scratch, using the example of a base64 codec written in Rust. It explains the concept of SIMD, its relation to physics and computer architecture, and how it can be used to improve performance. The article also delves into the details of SIMD instructions, including bitwise operations, lane-wise arithmetic, and shuffles. The author provides examples of SIMD code in Rust and discusses the challenges of optimizing code for SIMD architectures.

Main themes

• SIMD algorithm design
• Rust programming language
• Performance optimization
• Computer architecture
• Domain-specific languages
• C++ comparison
• Ergonomics and safety

What commenters say

• Rust's SIMD implementation can produce efficient code, but its ergonomics are poor compared to other languages.
• The use of SIMD instructions can result in significant performance gains, but it requires careful consideration of the underlying architecture.
• The Rust compiler is not always able to optimize SIMD code effectively, leading to suboptimal performance in some cases.
• The use of inline functions and careful optimization can significantly improve the performance of SIMD code in Rust.
• C++'s SIMD implementation is more mature and efficient than Rust's, but Rust's safety features make it a more attractive choice for systems programming.
• The development of a domain-specific language (DSL) for SIMD programming could improve the ergonomics and performance of SIMD code.
• The Clang extended vector extension is a good example of how to add portable SIMD to a language, but it has its own limitations and drawbacks.