Grid: OneCode and FourAPIs
Azusa Yamaguchi, Peter A. Boyle, Guido Cossu, Gianluca Filaci, Christoph Lehner, Antonin Portelli · Proceedings of The 38th International Symposium on Lattice Field Theory — PoS(LATTICE2021) · 2022
We discuss a substantial update to the Grid software library for Lattice QCD, enabling it to port to multiple GPU architectures while retaining CPU vectorisation and SIMD execution within OpenMP threads. The GPU environments supported include vendor specific Nvidia CUDA and AMD HIP environments and a (mostly) standards based SyCL implementation. This is performed by an internal abstraction interface giving single source cross-platform performance portability across all number of planned Exascale architectures, and all those planned by the US Department of Energy.