The Shift of Theseus — Toy Bit Provenance Abstract Domain
Summary
The PyPy blog post introduces a Toy Bit Provenance Abstract Domain for tracking bit provenance across SSA variables. It explains how the domain stores bit origins, implements transfer functions for bitwise operations, and uses dead code elimination, identity rewrites, and shift recognition to optimize long chains of bit operations. It also covers evaluation against PyPy and Pydrofoil workloads and discusses how bit provenance complements existing optimizations.