documented sampling.cuh

[yonikremer]

📌 Description

Hey, I had a hard time figuring out what is going on in sampling.cuh, after I figured it out I documented it. Yes an AI helped my and yes I read the documents and they are good in my opinion.

🔍 Related Issues

🚀 Pull Request Checklist

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Reviewer Notes

[gemini-code-assist[bot]]

Summary of Changes

Hello @yonikremer, I'm Gemini Code Assist[^1]! I'm currently reviewing this pull request and will post my feedback shortly. In the meantime, here's a summary to help you and other reviewers quickly get up to speed!

This pull request focuses on significantly improving the documentation within the include/flashinfer/sampling.cuh file. It introduces a comprehensive file-level overview and detailed Doxygen comments for nearly all CUDA kernels and host utilities related to softmax and token sampling. The goal is to enhance the clarity and understanding of the complex algorithms implemented, making the codebase more accessible and maintainable for current and future developers.

Highlights

• Comprehensive File Documentation: A detailed Doxygen comment has been added to the sampling.cuh header, providing a high-level overview of its purpose, design principles, threading model, error handling, and usage for softmax and token sampling.
• Function-Level Documentation: Extensive Doxygen comments have been introduced for numerous CUDA kernels and host utilities within sampling.cuh, including GetMinMaxValue, OnlineSoftmaxFusedKernel, SamplingFromLogitsKernel, TopKSamplingFromProbKernel, and OnlineSoftmax.
• Algorithmic Clarity: Inline comments have been added to clarify complex algorithmic details, such as the online merge rule for softmax, Gumbel-max sampling logic, CDF search mechanisms, and iterative pivot refinement in Top-K and Top-P sampling.
• Improved Readability: The added documentation significantly enhances the readability and maintainability of the sampling.cuh file, making it easier for developers to understand the intricate logic behind the high-performance CUDA primitives.

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