On Tue, 2025-02-11 at 23:08 +0300, Alexander Borisov wrote:
> I tried the approach via a range table. The result was worse than
> without the table. With branching in a function, the result is
> better.
>
> Patch v3 — ranges binary search by branches.
> Patch v4 — ranges binary search by table.
Thoughts on v3:
It looks like the top 5 bits of the offset are unused. What if we used
those bits for flags to indicate:
HAS_LOWER
HAS_UPPER
HAS_FOLD
HAS_SPECIAL
HAS_TITLE
That way, we only need to look in the corresponding table if it
actually has an entry other than the codepoint itself.
It doesn't leave a lot of room if the tables get larger, but if we are
worried about that, we could eliminate HAS_TITLE, because I don't think
the performance for INITCAP() is as important as LOWER/UPPER/CASEFOLD.
Regards,
Jeff Davis
