From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-ed1-x52e.google.com (mail-ed1-x52e.google.com [IPv6:2a00:1450:4864:20::52e]) by sourceware.org (Postfix) with ESMTPS id 2EC5838A8038 for ; Tue, 11 Jan 2022 13:27:01 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.1 sourceware.org 2EC5838A8038 Received: by mail-ed1-x52e.google.com with SMTP id a18so66112746edj.7 for ; Tue, 11 Jan 2022 05:27:01 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc:content-transfer-encoding; bh=R5qvF4sI7k25mt71BPzx8U5hljWnCStOuY1RTmuOc0Q=; b=kuRBSWThsXYioHitEL7Le8iQ6+W5ywsEgq/GSqgYH3q9i7K5lEKopoq1Du4vdgPTSc HDb2P1Pdojlytn7xe19s2lkTNuFiveofDkDIOEygRg9vVSnt40H1CKDl2UiKlaKunmpR eZrrFN64aa6DvZJs9q9kFmhW/HMY7vjkEJ5BGkaK7kKHjDzbdkSol14VuUbzd5Waop3G PtI0/QCEfOS5CFsXm3nqF8+H+PNZpHuox1qAh+Lo8m9XgdZcuCXbeyaHggyw0+UaEkp3 dcC/MREaZ1F8lbLOYkba2aZNJBUPXLUc/osKzLT+xvEAcy3pmBh9A9tpbLh46nAXXvkS DKKw== X-Gm-Message-State: AOAM532SKBHZjUyVIpe0S4uheXDO++EpnvAA3mH5VqODKlXrR11oORa4 j6JT/AhNY+cbznkKolkyPPx+l6ZeSrFKnvy8ggKimviS X-Google-Smtp-Source: ABdhPJziuwZeZxJU8sbrxuozH+SeteKQ1dqHhHULqRDEH99I9HATBEyIRcmlLYhVDbya6Z0OHjfBeumTlO9loBecwfs= X-Received: by 2002:a17:907:7f01:: with SMTP id qf1mr3610237ejc.240.1641907620199; Tue, 11 Jan 2022 05:27:00 -0800 (PST) MIME-Version: 1.0 References: <1935E1B7-16F3-4545-A5A2-4AEE720E5C7A@desy.de> In-Reply-To: <1935E1B7-16F3-4545-A5A2-4AEE720E5C7A@desy.de> From: Richard Biener Date: Tue, 11 Jan 2022 14:26:49 +0100 Message-ID: Subject: Re: GCC and OpenACC To: Mikel Mendizabal Cc: GCC Development Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Spam-Status: No, score=-2.1 required=5.0 tests=BAYES_00, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, DKIM_VALID_EF, FREEMAIL_FROM, RCVD_IN_DNSWL_NONE, 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: Tue, 11 Jan 2022 13:27:02 -0000 On Tue, Jan 11, 2022 at 1:52 PM Mikel Mendizabal via Gcc wrote: > > Dear GCC developers, > > In the past year we started the offload of our software to GPUs. We decid= ed to go with OpenACC. The program we are trying to offload is Millepede2 (= MP2), a tracker alignment software used to align the CMS experiment tracke= r at the large hadron collider. > > We are using gcc as our main compiler. However, we found a major inconven= ience with OpenACC 2.6, the REDUCTION clause does not accept arrays. Thus, = it not possible for us to parallelise our largest loops due to array depend= encies. We managed to offload MP2 for small datasets, we worked around the = reduction issue. Nonetheless, if our alignment campaign is large the workar= ounds are not useful anymore. > > I went thought the new versions of OpenACC and I found that v2.7 accepts = arrays for the REDUCTION clause. I was wondering if it is in your plans to = include a newer version of OpenACC for the next releases. Can you produce a self-contained example with an array for the REDUCTION clause that should be accepted with OpenACC v2.7? Thanks, Richard. > Sincerely, > Mikel Mendizabal