RFR: 8320500: [vectorapi] RISC-V: Optimize vector math operations with SLEEF [v4]

[Hamlin Li]

On Tue, 24 Sep 2024 06:59:58 GMT, Fei Yang <fyang at openjdk.org> wrote:

>> Note in the RISC-V ELF psABI there is a convention variant for v-regs.
>> If you add function attribute riscv_vector_cc it should be used for C/C++. (I never tested it)
>> v0 = first vector mask argument
>> v8-v23 = args/rets
>> v1-v7/v24-v31 = caller saved
>> 
>> https://github.com/riscv-non-isa/riscv-elf-psabi-doc/blob/master/riscv-cc.adoc
>
> Ah, I think I missed that. I was reading psABI spec 1.0 release. Thanks for this info.

Thanks Robbin for helping explaining!

minor correction: v1-v7/v24-v31 = callee saved

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PR Review Comment: https://git.openjdk.org/jdk/pull/21083#discussion_r1773530570