Optimization Remarks
Helping the Compiler Generate Better Code
Optimization remarks are Clang's logs of optimization passes, which include leads into optimization failures that might be mitigated. Deciphering raw optimization remarks seems a matter for compiler authors and select few experts, but a little-known tool called opt-viewer aims to change that - in particular with recent improvements by myself and others.
About 50% of the talk would be dedicated to real examples of missed optimizations. Most turn out to be escape-analysis and alias-analysis related, and we will devote time to discuss these in some depth.
We will also extend the discussion to other compilers and even other languages. (you really can't have a C++ presentation in Sep 2022 without at least mentioning Rust and Carbon).
If you care about performance there's an excellent chance you'd leave this talk with immediately actionable insights and surprising ways to check and improve your code in performance bottlenecks.
Ofek Shilon
20Y C++ developer, writer and speaker in both the Linux and MS universes. Fascinated by compilers, debuggers and pretty much anything low level. Fiercely hated by his cat for no apparent reason.