About

Hi! My name is Kohei Asano, I use khei4 on the Internet.

I’m a Software Engineer at Sony Interactive Entertainment, mainly working on PS5 WebKit. I love the (Soft/Hardware, any)Engineers and creators to make the world convenient/humorous/swift, I wanna become one of them. I wanna contribute the tools that help those Engineers.

I studied Mathematics at the University of Hokkaido and Computer Science at the University of Tokyo.

Feel free to contact me via GitHub, LinkedIn, X.

Projects

• Selected Fellow, IPA Mitou 2023 – “RiP: High-Efficiency Reservoir-in-Processor Computing Utilizing Internal State of RISC-V Processors” (Ja)
  • Designed a reservoir-computing architecture that re-uses RISC-V micro-architectural state as the nonlinear reservoir.
  • I created RISC-V cycle-accurate emulator, that has branch predictions and stats calculator for that.

OSS

• LLVM – Middle-end passes, MemCpyOpt, InstCombine as Google Summer of Code 2023 and more.
  • Google Summer of Code Final Report
    • Japanese Blog about that

• WebKit – Windows Rendering, and Refactorings.

• Reservoir-In-Processor RISC-V Simulator – RISC-V cycle-level emulator, with CI/CD, Statistics, cycle-level registers dump.

• Polynomial Invariant calculator – Rust implementation of C-subset Parser and Algebraic Invariant Computation using Groebner basis for my Undergraduate Poster session.

• Symbolic Differentiator – Rust implementation of Mathematical Expression Parser and Differentiation algorithm on the paper.
  • English slides
  • Japanese blog
• Corner Case Faker Fuzzer – Golang Generics Function’s Type-Level Fuzzer exploiting fuzzing and generics on GoLang 1.18.

Presentations

• Presentation about Stack-Move Optimization I implemented on GSoC at Kernel/VM探検隊 No16 (English slides, Japanese video)

• Presentation about Undergraduate Poster: Inference of polynomial invariants for imperative programs (English slides)

• Introduction of Clippy await warning about Lock/RefCellRef (Japanese slides, Japanese Blog)

• Survey about Syntax-Guided Synthesis (English slides)

• Eulerian cycle, Rust, Bit tricks at Hokkaido University HUIT-Club Seminar.(Japanese slides)

Theses and Posters

• Rust Implementation of Polynomial Invariant Computation using Groebner Basis[Undergraduate Mathematics] (slides)

• Could LLM be LLVM superoptimizer? [xSig 2023] (Japanese poster)
  • I implemented LLVM middle-end path, that asks ChatGPT to optimize the peephole optimization tests, and evaluate them by llvm-mca.
  • Got Poster Award.
• Master Thesis: Finding Missing Automatic Vectorization Opportunity by Differential Testing [Graduate CS] (pdf, Japanese slides)

Miscellaneous

• TOEIC Reading & Listening 840 [2024/09]

• TechBookFest Japanese Leaflet writing Explaining about LLVM overview and steps tweaking LLVM Frontend to parse Python-subset language.

• LifeGame by pure JS A JS-practice implementation of Conway’s Game of Life, configurable in detail.