On Problems in OpenBLAS Library Usage in Productized Code on RISC-V

The boundary element method usage for the numerical simulation in continuum mechanics problems leads to the need to solve a system of linear algebraic equations with a dense matrix. The de facto standards for the interface of functions over dense matrices and vectors software implementations are BLAS/LAPACK. Among the optimized open-source BLAS/LAPACK implementations, only the OpenBLAS library includes optimizations for the widest range of hardware platforms. This library is optimized for Intel, AMD, ARM and RISC-V architectures. The open RISC-V architecture ecosystem is currently actively developing. European supercomputing centers have opened RISC-V competence centers as part of the government's EuroHPC grant support, since solutions based on the ARM architecture are not recognized as part of the European initiative to develop its own technological independence. Currently, companies included in the international RISC-V consortium are developing not only high-performance RISC-V processors, but also AI accelerators, as well as video cards based on RISC-V architecture. OpenBLAS is actively supported and optimized for emerging RISC-V hardware and extensions. However, libraries used in product code are traditionally subject to strict requirements for stability and reliability in order to minimize possible errors and failures in the product. As it turned out, from this point of view, OpenBLAS has a number of problems that we had to solve in order to productize this library. In this article the OpenBLAS test system is described, the problems of testing the LAPACK functionality of the library and ways to solve them are discussed. In addition, the test coverage of the BLAS functionality is analyzed and the results achieved in increasing it are presented. It is planned to contribute the described changes to the OpenBLAS project.

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