Agile Acceleration of LLVM Flang Support for Fortran 2018 Parallel Programming

Conference · 15 November 2022

DOI:https://doi.org/10.25344/S4CP4S· OSTI ID:1886637

Rasmussen, Katherine; Rouson, Damian; George, Najé; Bonachea, Dan; Kadhem, Hussain; Friesen, Brian

The LLVM Flang compiler ("Flang") is currently Fortran 95 compliant, and the frontend can parse Fortran 2018. However, Flang does not have a comprehensive 2018 test suite and does not fully implement the static semantics of the 2018 standard. We are investigating whether agile software development techniques, such as pair programming and test-driven development (TDD), can help Flang to rapidly progress to Fortran 2018 compliance. Because of the paramount importance of parallelism in high-performance computing, we are focusing on Fortran’s parallel features, commonly denoted “Coarray Fortran.” We are developing what we believe are the first exhaustive, open-source tests for the static semantics of Fortran 2018 parallel features, and contributing them to the LLVM project. A related effort involves writing runtime tests for parallel 2018 features and supporting those tests by developing a new parallel runtime library: the CoArray Fortran Framework of Efficient Interfaces to Network Environments (Caffeine).

• Research Organization: Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
• Sponsoring Organization: USDOE Office of Science (SC), Advanced Scientific Computing Research (ASCR)
• DOE Contract Number: AC02-05CH11231
• OSTI ID: 1886637
• Resource Relation: Conference: International Conference on High Performance Computing, Networking, Storage and Analysis (SC22), November 2022
• Country of Publication: United States
• Language: English