On Mon, 31 Oct 2022 22:06:20 GMT, Claes Redestad <redes...@openjdk.org> wrote:
>> No you don't need to, the vector loop can be calculated as: >> >> IntVector accumulation = IntVector.zero(INT_SPECIES); >> for (int i = 0; i < bound; i += INT_SPECIES.length()) { >> IntVector current = IntVector.load(INT_SPECIES, array, i); >> accumulation = >> accumulation.mul(31**(INT_SPECIES.length())).add(current); >> } >> return accumulation.mul(IntVector.of(31**INT_SPECIES.length() - 1, ..., >> 31**2, 31, 1).reduce(ADD); >> >> Each iteration only requires a multiplication and an addition. The weight of >> lanes can be calculated just before the reduction operation. > > Ok, I can try rewriting as @merykitty suggests and compare. I'm running out > of time to spend on this right now, though, so I sort of hope we can do this > experiment as a follow-up RFE. @cl4es i can write the assembly and send it your way if you want ------------- PR: https://git.openjdk.org/jdk/pull/10847