Use POWER8 and POWER9 ISA enhancements to improve the performance of GHASH. Demonstrate why achieved performance of AES-GCM is close to optimal for the platform (i.e matching or beating OpenSSL performance).
Optimized assembly implementations in the Cryptogams repository may serve as useful reference. C-based intrinsic implementations are discouraged. Financial bounty upon completion, community acceptance of patches, and bounty reviewer input.