From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <gcc-bugzilla@gcc.gnu.org>
Received: by sourceware.org (Postfix, from userid 48)
	id 8B5AB395B44D; Wed, 16 Nov 2022 15:34:07 +0000 (GMT)
DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 8B5AB395B44D
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gcc.gnu.org;
	s=default; t=1668612847;
	bh=DaZ349vo4+pQbDZdX0lfIY0nVYQnRt5R0qPFNhbZlWo=;
	h=From:To:Subject:Date:In-Reply-To:References:From;
	b=oavzaaiCVc7UXDoAVmP9mMRJpL+bYLW5OHFlQsPtBRTR7a/YS4MWtAqXpBuSMsIbl
	 BWe8F4LzwpB/ghXIZXHY5qOKXugkgxaIDTqLllFBStLqiWcucZYb8qeL8PDIbTinpk
	 x7q+/JcJcmkcxkXA11FHxju62EbLKKnB4N6G1zmk=
From: "hubicka at ucw dot cz" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug target/87832] AMD pipeline models are very costly size-wise
Date: Wed, 16 Nov 2022 15:34:06 +0000
X-Bugzilla-Reason: CC
X-Bugzilla-Type: changed
X-Bugzilla-Watch-Reason: None
X-Bugzilla-Product: gcc
X-Bugzilla-Component: target
X-Bugzilla-Version: 9.0
X-Bugzilla-Keywords: 
X-Bugzilla-Severity: normal
X-Bugzilla-Who: hubicka at ucw dot cz
X-Bugzilla-Status: UNCONFIRMED
X-Bugzilla-Resolution: 
X-Bugzilla-Priority: P3
X-Bugzilla-Assigned-To: unassigned at gcc dot gnu.org
X-Bugzilla-Target-Milestone: ---
X-Bugzilla-Flags: 
X-Bugzilla-Changed-Fields: 
Message-ID: <bug-87832-4-mwgxhnAASf@http.gcc.gnu.org/bugzilla/>
In-Reply-To: <bug-87832-4@http.gcc.gnu.org/bugzilla/>
References: <bug-87832-4@http.gcc.gnu.org/bugzilla/>
Content-Type: text/plain; charset="UTF-8"
Content-Transfer-Encoding: quoted-printable
X-Bugzilla-URL: http://gcc.gnu.org/bugzilla/
Auto-Submitted: auto-generated
MIME-Version: 1.0
List-Id: <gcc-bugs.sourceware.org>

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D87832

--- Comment #9 from Jan Hubicka <hubicka at ucw dot cz> ---
>=20
> Do you mean we should fix modeling of divisions there as well? I don't ha=
ve
> latency/throughput measurements for those CPUs, nor access so I can run
> experiments myself, unfortunately.
>=20
> I guess you mean just making a patch to model division units separately,
> leaving latency/throughput as in current incorrect models, and leave it to
> manufacturers to correct it? Alternatively, for AMD Bobcat and Bulldozer =
we
> might be able to crowd-source it eventually.
Actually for older cores I think the manufacturers do not care much.  I
still have a working Bulldozer machine and I can do some testing.
I think in Buldozer case I was basing the latency throughput on data in
Agner Fog's manuals.  How do you test it?
Honza=