Alvaro Herrera writes:
> (BTW, my reading of the articles I cited, as well as my own runs of the
> test programs therein, suggest that in order to get a really good
> performance improvement you need to hand-code calls to the POPCNT
> instruction in assembly rather than rely on the compiler intrin
Alvaro Herrera writes:
> On 2019-Feb-15, Tom Lane wrote:
>> Sure, I'll pick it up. I agree it's probably a marginal performance
>> change, but it seems a shame to give up when we were 80% of the way
>> there.
> (BTW, my reading of the articles I cited, as well as my own runs of the
> test progra
On 2019-Feb-15, Tom Lane wrote:
> Alvaro Herrera writes:
> > 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.
>
> Sure, I'll pick it up. I agree it's probably a marginal performance
> change, but it see
Alvaro Herrera writes:
> 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.
Sure, I'll pick it up. I agree it's probably a marginal performance
change, but it seems a shame to give up when we were 80% of the
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
>
Alvaro Herrera writes:
> Hmm, this should fix the build, but I'm rushing out to lunch -- maybe
> I'm missing something.
> diff --git a/src/port/pg_bitutils.c b/src/port/pg_bitutils.c
> index 97bfcebe4e1..e0198f3ab35 100644
> --- a/src/port/pg_bitutils.c
> +++ b/src/port/pg_bitutils.c
> @@ -90,9 +
Hmm, this should fix the build, but I'm rushing out to lunch -- maybe
I'm missing something.
diff --git a/src/port/pg_bitutils.c b/src/port/pg_bitutils.c
index 97bfcebe4e1..e0198f3ab35 100644
--- a/src/port/pg_bitutils.c
+++ b/src/port/pg_bitutils.c
@@ -90,9 +90,11 @@ pg_popcount_available(void)
Fix compiler builtin usage in new pg_bitutils.c
Split out these new functions in three parts: one in a new file that
uses the compiler builtin and gets compiled with the -mpopcnt compiler
option if it exists; another one that uses the compiler builtin but not
the compiler option; and finally the f
