RFR: 8337632: AES-GCM Algorithm optimization for x86_64 [v3]

[Smita Kamath]

On Fri, 6 Sep 2024 09:04:50 GMT, Jatin Bhateja <jbhateja at openjdk.org> wrote:

>> Smita Kamath has updated the pull request incrementally with one additional commit since the last revision:
>> 
>>   Updated copyright dates and addressed review comments
>
> src/hotspot/cpu/x86/stubGenerator_x86_64_aes.cpp line 3001:
> 
>> 2999:   if (do_reduction) {
>> 3000:   //new reduction
>> 3001:     __ evmovdquq(ZTMPB, ExternalAddress(ghash_polynomial_addr()), Assembler::AVX_512bit, rbx /*rscratch*/);
> 
> Is this based on aggregate reduction method ? 
> Can you please add some comments to narrate the reduction algorithm.

The reduction algorithm is mentioned in the paper - https://github.com/intel/intel-ipsec-mb/wiki/doc/advanced-encryption-standard-galois-counter-mode-optimized-ghash-function-technology-guide-1693300747.pdf

-------------

PR Review Comment: https://git.openjdk.org/jdk/pull/17515#discussion_r1771745843