On Sat, Jan 31, 2026 at 10:45 AM David Rowley <dgrowleyml@gmail.com> wrote:
> On Sat, 31 Jan 2026 at 15:48, John Naylor <johncnaylorls@gmail.com> wrote:
> > pg_rightmost_one_pos32(~((uint32) bits[bytenum]))
>
> I'd rather handle that in a single byte as the fallback path in that
> function requires byte-at-a-time processing.
I spot checked some less common animals in the buildfarm and i686,
ppc64le, riscv64, loongarch64, and s390x all have the builtin. Of
these, only riscv64 seems to lack a single instruction implementation.
It's good to keep the old fallback path around just in case, but I
doubt a new fallback would get any coverage at all.
--
John Naylor
Amazon Web Services
