| From: | Alvaro Herrera <alvherre(at)2ndquadrant(dot)com> |
|---|---|
| To: | Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> |
| Cc: | pgsql-committers(at)lists(dot)postgresql(dot)org |
| Subject: | Re: pgsql: Fix compiler builtin usage in new pg_bitutils.c |
| Date: | 2019-02-15 19:36:49 |
| Message-ID: | 20190215193649.GA32096@alvherre.pgsql |
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| Thread: | |
| Lists: | pgsql-committers |
On 2019-Feb-15, Tom Lane wrote:
> Meh. I don't see why this entire function should exist if there
> is nothing for it to do. I'm inclined to think that somewhere
> there needs to be a symbol NEED_POPCOUNT_CHOOSING that is only
> enabled if we have all three of HAVE__BUILTIN_POPCOUNT, nonempty
> CFLAGS_POPCOUNT, and HAVE__GET_CPUID || HAVE__CPUID. Possibly
> we should gate building of pg_bitutils_hwpopcnt.c that way too?
> Not much point in building that file if we have no way to figure
> out when to use it.
I'm done with this stuff. Anybody feel free to run with it, but for a
barely noticeable performance improvement it's not going to be me.
--
Álvaro Herrera https://www.2ndQuadrant.com/
PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services
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