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

On Mon, Sep 15, 2014 at 7:21 PM, Peter Geoghegan <pg@heroku.com> wrote:
> On Mon, Sep 15, 2014 at 11:25 AM, Peter Geoghegan <pg@heroku.com> wrote:
>> OK, I'll draft a patch for that today, including similar alterations
>> to varstr_cmp() for the benefit of Windows and so on.
>
> I attach a much simpler patch, that only adds an opportunistic
> "memcmp() == 0" before a possible strcoll().  Both
> bttextfastcmp_locale() and varstr_cmp() have the optimization added,
> since there is no point in leaving anyone out for this part.

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.

-- 
Robert Haas
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