PGO (Profile-Guided Optimisation) Purpose Guide agents through the full PGO workflow: instrument build → representative workload → collect profile → optimised build, covering both GCC and Clang, plus BOLT for post-link optimisation. Triggers - "How do I use PGO to speed up my binary?" - "What is profile-guided optimization and when should I use it?" - "How do I use and ?" - "My build isn't fast enough — what next?" - "How does BOLT differ from PGO?" - "How do I collect representative profile data?" Workflow 1. When to use PGO PGO helps most with: - Large binaries with many cold/hot code paths…