RFR: 8373069: RISC-V: implement GHASH intrinsic [v4]

[Fei Yang]

On Thu, 11 Dec 2025 12:22:13 GMT, Anjian Wen <wenanjian at openjdk.org> wrote:

>> support GHASH intrinsic for crypt GCM, which need zvkg extension. 
>> 
>> passed the tests in 
>> test/hotspot/jtreg/compiler/codegen/aes/
>> test/jdk/com/sun/crypto
>
> Anjian Wen has updated the pull request incrementally with one additional commit since the last revision:
> 
>   modify format

src/hotspot/cpu/riscv/stubGenerator_riscv.cpp line 3021:

> 3019:     assert(UseZvkg, "need GHASH instructions (Zvkg extension) support");
> 3020: 
> 3021:     __ align(CodeEntryAlignment);

Can you move this line to immediately before L3025? Like:

    __ align(CodeEntryAlignment);
    address start = __ pc();
    __ enter();


Then it looks more obvious where we want to align the code. BTW: Seems CBC and CTR intrinsics need similar adjustment.

src/hotspot/cpu/riscv/stubGenerator_riscv.cpp line 3052:

> 3050:       __ vghsh_vv(partial_hash, hash_subkey, cipher_text);
> 3051:       __ subi(blocks, blocks, 1);
> 3052:       __ bnez(blocks, L_ghash_loop);

Please leave a new line after the loop.

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

PR Review Comment: https://git.openjdk.org/jdk/pull/28548#discussion_r2617702776
PR Review Comment: https://git.openjdk.org/jdk/pull/28548#discussion_r2617699025