On Sat, Mar 13, 2021 at 4:37 AM John Naylor
<john(dot)naylor(at)enterprisedb(dot)com> wrote:
> On Fri, Mar 12, 2021 at 9:14 AM Amit Khandekar <amitdkhan(dot)pg(at)gmail(dot)com> wrote:
> > I was not thinking about auto-vectorizing the code in
> > pg_validate_utf8_sse42(). Rather, I was considering auto-vectorization
> > inside the individual helper functions that you wrote, such as
> > _mm_setr_epi8(), shift_right(), bitwise_and(), prev1(), splat(),
>
> If the PhD holders who came up with this algorithm thought it possible to do it that way, I'm sure they would have. In reality, simdjson has different files for SSE4, AVX, AVX512, NEON, and Altivec. We can incorporate any of those as needed. That's a PG15 project, though, and I'm not volunteering.
Just for fun/experimentation, here's a quick (and probably too naive)
translation of those helper functions to NEON, on top of the v15
patch.