XcalableACC: An Integration of XcalableMP and OpenACC

XcalableACC (XACC) is an extension of XcalableMP for accelerated clusters. It is defined as a diagonal integration of XcalableMP and OpenACC, which is another directive-based language designed to program heterogeneous CPU/accelerator systems. XACC has features for handling distributed-memory parallelism, inherited from XMP, offloading tasks to accelerators, inherited from OpenACC, and two additional functions: data/work mapping among multiple accelerators and direct communication between accelerators.