Truly Final Fields in Java - Optimization and Implementation

Explore the intricacies of final fields in Java and their optimization in this 37-minute talk by Anna Thomas. Dive deep into the implementation of truly final dependency tracking and invalidation in the Zing JVM, as well as the optimizations performed within the Falcon LLVM-based JIT compiler. Learn about the challenges of implementing final field optimizations, including constant folding, and understand the differences between static and instance final fields. Discover the callback mechanism in Falcon that allows querying the VM about field finality. Examine specific examples demonstrating the benefits of truly final optimizations and gain insights into planned improvements for effectively final fields. Gain a comprehensive understanding of final semantics according to JLS and JVM specs, dependency tracking, and the key extensions made to LLVM for final field optimizations.