Re: B-Tree support function number 3 (strxfrm() optimization)

On Tue, Sep 16, 2014 at 4:55 PM, Peter Geoghegan <pg(at)heroku(dot)com> wrote:
> On Tue, Sep 16, 2014 at 1:45 PM, Robert Haas <robertmhaas(at)gmail(dot)com> wrote:
>> Even though our testing seems to indicate that the memcmp() is
>> basically free, I think it would be good to make the effort to avoid
>> doing memcmp() and then strcoll() and then strncmp(). Seems like it
>> shouldn't be too hard.
>
> Really? The tie-breaker for the benefit of locales like hu_HU uses
> strcmp(), not memcmp(). It operates on the now-terminated copies of
> strings. There is no reason to think that the strings must be the same
> size for that strcmp(). I'd rather only do the new opportunistic
> "memcmp() == 0" thing when len1 == len2. And I wouldn't like to have
> to also figure out that it's safe to use the earlier result, because
> as it happens len1 == len2, or any other such trickery.

OK, good point. So committed as-is, then, except that I rewrote the
comments, which I felt were excessively long for the amount of code.

--
Robert Haas
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