Accl++ : A high-productivity programming language for performance and code portability on heterogeneous systems
Marc Gonzalez, Pedro Valero, Mohammad Alaul Haque Monil, Seyong Lee, Beau Johnston, Aaron Young, Narasinga Rao Miniskar, Keita Teranishi, Jeff Vetter · Future Generation Computer Systems · 2026
This work describes the Accl++ programming language for heterogeneous computing. Accl++ is embedded in the C++ language and implemented as a C++ library. The language allows for describing device code and execution libraries and includes primitives for runtime compilation (RTC), thereby enabling code portability across disparate devices. Here, we demonstrate Accl++’s capability by coding different benchmarks from different domains. This work also describes an analysis of the overheads introduced by the Accl++ RTC support as well as the performance of the generated code for the Accl++ kernels. Accl++ improves heterogeneous code portability without incurring high levels of overhead. In two different heterogeneous systems—one composed of two 32-core AMD EPYC 7513 CPUs and two NVIDIA A100 GPUs and the other composed of two 12-core AMD EPYC 7272 CPUs and two AMD MI100 GPUs—Accl++ enables the execution of the same binary application with observed RTC overheads in the range of 3%–10% of the total kernel execution time, resulting in performance levels similar to those of native CUDA/HIP/OpenCL code.