Youngsuk Kim (김영석)

Work History

• Systems Software Engineer 2 @ Hewlett Packard Enterprise (Sep 2021 - Now)
• Clang/LLVM Compiler Intern @ Hewlett Packard Enterprise (May 2021 - Aug 2021)

Education

• MS Computer Science @ Georgia Tech (Aug 2018 - Aug 2021)
• BS Computer Science & Engineering @ Korea University (Mar 2014 - Feb 2018)

Publications

• Bae, Y., Kim, Y., Askar, A., Lim, J., & Kim, T. (2021, October). Rudra: finding memory safety bugs in rust at the ecosystem scale. In Proceedings of the ACM SIGOPS 28th Symposium on Operating Systems Principles (pp. 84-99).
  • Rudra : memory safety bug finder (compiler plugin)
  • Rudra-PoC : Collection of open-source Rust bugs discovered by Rudra

Open-Source Contributions

LLVM Compiler Infrastructure

• Clang diagnostics
  • Warn unused cxx vardecl which entirely consists condition expr of if/while/for construct
  • Warn when a function returns pointer/reference to a struct literal
  • Prevent running duplicate semantic checks on AST
  • Warn consecutive builtin comparisons in an expression
  • Don’t emit ‘declared here’ note for builtin functions with no decl in source
• Clang
  • Prevent dangling StringRefs that lead to use-after-free bug
• LLVM
  • Opaque pointer clean-up
    • Remove old APIs which are no longer needed with opaque pointers
    • Remove no-op ptr-to-ptr bitcasts
    • Special thanks to @nikic & @s-barannikov for reviewing my initial commits!
  • [loop-reduce] Fix assertion failure due to violated invariant
  • Remove .flush() calls on the always unbuffered llvm::raw_string_ostream
  • Verify 69 old bugs from LLVM Bugzilla
• LLVM NVPTX backend
  • Don’t reorder or split up MIs that must stick together to construct a valid PTX function call
  • Prevent emitting dead PTX .reg variable
  • Don’t emit extraneous +0 immediate offset part in PTX loads & stores

“Writing an OS in Rust” Blog (edition-2)

• Authored official Korean translation of chapters 1 ~ 7
• Special thanks to the reviewers! (@Quqqu & @KimWang906 & @dalinaum & @phil-opp)

MIRI : Rust MIR Interpreter

• Improved support for running MIRI on Windows
  • Implement environment variable emulation on Windows
  • Windows: cannot create Instants
• Special thanks to @RalfJung & @pvdrz who mentored me through the process!