From: Tom Lane <tgl@sss.pgh.pa.us>
To: Alvaro Herrera <alvherre@2ndquadrant.com>
cc: Kyotaro HORIGUCHI <horiguchi.kyotaro@lab.ntt.co.jp>, andres@anarazel.de,
        thomas.munro@enterprisedb.com, andrew@tao11.riddles.org.uk,
        david.rowley@2ndquadrant.com, pgsql-hackers@lists.postgresql.org
Subject: Re: Using POPCNT and other advanced bit manipulation instructions
In-reply-to: <20190215161840.GA13026@alvherre.pgsql>
References: <20190215161840.GA13026@alvherre.pgsql>
Comments: In-reply-to Alvaro Herrera <alvherre@2ndquadrant.com>
	message dated "Fri, 15 Feb 2019 13:18:40 -0300"
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Date: Fri, 15 Feb 2019 11:36:15 -0500
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Alvaro Herrera <alvherre@2ndquadrant.com> writes:
> Here's a final version that I intend to push shortly, to have time
> before EOB today to handle any fallout.

I think this is likely to result in a lot of complaints about
rightmost_one_pos[] being unreferenced, in non-HAVE__BUILTIN_CTZ
builds.  Probably that has to be an extern rather than static
in the header.  leftmost_one_pos[] likewise.

I might have a go at improving the configure tests later ---
I still don't like that they're compile-time-optimizable.
But that can wait.

			regards, tom lane