From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by sourceware.org (Postfix) with ESMTPS id 952793858D39 for ; Wed, 2 Mar 2022 15:24:53 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.1 sourceware.org 952793858D39 Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-567-ehY1j2jLNByd-Io4ma63Ew-1; Wed, 02 Mar 2022 10:24:52 -0500 X-MC-Unique: ehY1j2jLNByd-Io4ma63Ew-1 Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.phx2.redhat.com [10.5.11.22]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 14CABFC81; Wed, 2 Mar 2022 15:24:51 +0000 (UTC) Received: from tucnak.zalov.cz (unknown [10.39.192.81]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 9E15F1057F7B; Wed, 2 Mar 2022 15:24:50 +0000 (UTC) Received: from tucnak.zalov.cz (localhost [127.0.0.1]) by tucnak.zalov.cz (8.16.1/8.16.1) with ESMTPS id 222FOlAg1054864 (version=TLSv1.3 cipher=TLS_AES_256_GCM_SHA384 bits=256 verify=NOT); Wed, 2 Mar 2022 16:24:48 +0100 Received: (from jakub@localhost) by tucnak.zalov.cz (8.16.1/8.16.1/Submit) id 222FOleo1054863; Wed, 2 Mar 2022 16:24:47 +0100 Date: Wed, 2 Mar 2022 16:24:46 +0100 From: Jakub Jelinek To: "Stubbs, Andrew" Cc: "gcc@gcc.gnu.org" Subject: Re: OpenMP auto-simd Message-ID: Reply-To: Jakub Jelinek References: <2213264c2c5c467fb491f71051173873@svr-ies-mbx-01.mgc.mentorg.com> MIME-Version: 1.0 In-Reply-To: <2213264c2c5c467fb491f71051173873@svr-ies-mbx-01.mgc.mentorg.com> X-Scanned-By: MIMEDefang 2.84 on 10.5.11.22 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=us-ascii Content-Disposition: inline X-Spam-Status: No, score=-5.3 required=5.0 tests=BAYES_00, DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, DKIM_VALID_EF, RCVD_IN_DNSWL_LOW, RCVD_IN_MSPIKE_H5, RCVD_IN_MSPIKE_WL, SPF_HELO_NONE, SPF_NONE, TXREP, T_SCC_BODY_TEXT_LINE 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, 02 Mar 2022 15:24:54 -0000 On Wed, Mar 02, 2022 at 03:12:30PM +0000, Stubbs, Andrew wrote: > Has anyone ever considered having GCC add the "simd" clause to offload (or regular) loop nests automatically? > > For example, something like "-fomp-auto-simd" would transform "distribute parallel" to "distribute parallel simd" automatically. Loop nests that already contain "simd" clauses or directives would remain unchanged, most likely. I'm afraid we can't do that, at least not always. The simd has various restrictions on what can appear inside of the body, etc. and we shouldn't reject valid code just because we decided to add simd automatically (even if the user asked for those through an option). So, it could be done only if we would do analysis that it is safe to do that. Jakub