From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx0a-001b2d01.pphosted.com (mx0a-001b2d01.pphosted.com [148.163.156.1]) by sourceware.org (Postfix) with ESMTPS id BB19C3858C39; Wed, 6 Oct 2021 19:30:10 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.1 sourceware.org BB19C3858C39 Received: from pps.filterd (m0098396.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.1.2/8.16.1.2) with SMTP id 196IVxDm029091; Wed, 6 Oct 2021 15:30:08 -0400 Received: from pps.reinject (localhost [127.0.0.1]) by mx0a-001b2d01.pphosted.com with ESMTP id 3bha60w83k-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Wed, 06 Oct 2021 15:30:08 -0400 Received: from m0098396.ppops.net (m0098396.ppops.net [127.0.0.1]) by pps.reinject (8.16.0.43/8.16.0.43) with SMTP id 196JK0TM005995; Wed, 6 Oct 2021 15:30:08 -0400 Received: from ppma04dal.us.ibm.com (7a.29.35a9.ip4.static.sl-reverse.com [169.53.41.122]) by mx0a-001b2d01.pphosted.com with ESMTP id 3bha60w831-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Wed, 06 Oct 2021 15:30:08 -0400 Received: from pps.filterd (ppma04dal.us.ibm.com [127.0.0.1]) by ppma04dal.us.ibm.com (8.16.1.2/8.16.1.2) with SMTP id 196JS6oV004195; Wed, 6 Oct 2021 19:30:07 GMT Received: from b03cxnp08026.gho.boulder.ibm.com (b03cxnp08026.gho.boulder.ibm.com [9.17.130.18]) by ppma04dal.us.ibm.com with ESMTP id 3bef2cnyaj-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Wed, 06 Oct 2021 19:30:07 +0000 Received: from b03ledav003.gho.boulder.ibm.com (b03ledav003.gho.boulder.ibm.com [9.17.130.234]) by b03cxnp08026.gho.boulder.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 196JU5Mi30605812 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Wed, 6 Oct 2021 19:30:05 GMT Received: from b03ledav003.gho.boulder.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 08AC06A04D; Wed, 6 Oct 2021 19:30:05 +0000 (GMT) Received: from b03ledav003.gho.boulder.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id F28AA6A082; Wed, 6 Oct 2021 19:30:03 +0000 (GMT) Received: from [9.160.170.208] (unknown [9.160.170.208]) by b03ledav003.gho.boulder.ibm.com (Postfix) with ESMTP; Wed, 6 Oct 2021 19:30:03 +0000 (GMT) Subject: Re: libgfortran.so SONAME and powerpc64le-linux ABI changes To: Segher Boessenkool , Jakub Jelinek Cc: Michael Meissner , gcc@gcc.gnu.org, Thomas Koenig , fortran@gcc.gnu.org, Tobias Burnus , Jonathan Wakely References: <20211004141410.GP304296@tucnak> <6d845542-536e-1a0f-70e9-d05eea98aae7@netcologne.de> <20211005215450.GC10333@gate.crashing.org> <90df1250-9b3f-4a55-bc67-e3e05e54f7ef@netcologne.de> <20211006151744.GE10333@gate.crashing.org> <20211006154107.GK304296@tucnak> <20211006160730.GG10333@gate.crashing.org> <20211006163433.GM304296@tucnak> <20211006165937.GI10333@gate.crashing.org> <20211006170743.GN304296@tucnak> <20211006175041.GJ10333@gate.crashing.org> From: Peter Bergner Message-ID: Date: Wed, 6 Oct 2021 14:30:03 -0500 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:78.0) Gecko/20100101 Thunderbird/78.14.0 MIME-Version: 1.0 In-Reply-To: <20211006175041.GJ10333@gate.crashing.org> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit X-TM-AS-GCONF: 00 X-Proofpoint-GUID: sAQzUnAbBMtJENUCBXzSv0ZgvOjJQwtD X-Proofpoint-ORIG-GUID: 7QtjrWJ3sfAFxX4tM7uTbIbYWoCF8m03 X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.182.1,Aquarius:18.0.790,Hydra:6.0.391,FMLib:17.0.607.475 definitions=2021-10-06_04,2021-10-06_01,2020-04-07_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 impostorscore=0 mlxscore=0 mlxlogscore=999 phishscore=0 priorityscore=1501 bulkscore=0 adultscore=0 malwarescore=0 spamscore=0 suspectscore=0 lowpriorityscore=0 clxscore=1011 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2109230001 definitions=main-2110060118 X-Spam-Status: No, score=-4.4 required=5.0 tests=BAYES_00, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_EF, NICE_REPLY_A, RCVD_IN_MSPIKE_H2, SPF_HELO_NONE, SPF_PASS, TXREP autolearn=ham autolearn_force=no version=3.4.4 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on server2.sourceware.org X-BeenThere: gcc@gcc.gnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Gcc mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 06 Oct 2021 19:30:12 -0000 On 10/6/21 12:50 PM, Segher Boessenkool wrote: > So we have three options (well, four): > > 0) Do nothing. We will stay in this hell forever. Not my choice :-) > 1) Use a soft-float-like parameter passing everywhere. This works but > will be horridly slow on newer systems. We can do better than that. > 2) Use the current setup where -mcpu=power8 (or later) makes QP float > available. Most BE stuff isn't compiled with that currently, and it > will split our ecosystem. > 3) As Joseph reminds me the high VSRs are the VRs, so we could use the > same parameter passing on anything with AltiVec. We could even > simply require -maltivec for QP float to be supported (we currently > require -mvsx, this would not be a restriction). > > I think I like 3) :-) I like 3 too, meaning requiring -maltivec to support IEEE QP at all. This would cover POWER6 and later server CPUs, as well as some other cpus like in the Power Macs. Anything without Altivec hardware would need to either not support IEEE QP at all, or go through the work themselves of coming up with a -msoft-altivec like ABI. Peter