Argonne computational scientist Hal Finkel will deliver a keynote talk on the open-source LLVM compiler infrastructure at the Workshop on Programming and Performance Visualization Tools (ProTools 19). LLVM, winner of the 2012 ACM Software System Award, has become an integral part of the software-development ecosystem for optimizing compilers, dynamic-language execution engines, source-code analysis and transformation tools, debuggers and linkers, and a host of other programming language- and toolchain-related components. Finkel will discuss various LLVM technologies, HPC tooling use cases, challenges in using these technologies in HPC environments, and interesting opportunities for the future.