In this text, the author explores different strategies for achieving SIMD-ized division of 8-bit unsigned numbers through floating-point division and the long division algorithm. Compilers struggle to vectorize the simple scalar division procedure provided in C++, leading to manual optimizations. The long division algorithm is detailed in both general and SSE implementation, taking advantage of bitwise operations and conditional updates. The use of approximate reciprocal is highlighted as a method to enhance performance by leveraging instruction sets like RCPPS. The author provides implementation details for SSE and AVX2 architectures, showcasing efficient SIMD division operations. This thorough exploration sheds light on complex SIMD optimizations in the realm of division.
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