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 69A823858D35 for ; Fri, 3 Dec 2021 14:15:30 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.1 sourceware.org 69A823858D35 Received: from mail-qv1-f72.google.com (mail-qv1-f72.google.com [209.85.219.72]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-303-dnGCbLozNwGfGNxxA8ri4w-1; Fri, 03 Dec 2021 09:15:29 -0500 X-MC-Unique: dnGCbLozNwGfGNxxA8ri4w-1 Received: by mail-qv1-f72.google.com with SMTP id e14-20020a0562140d8e00b003bace92a1feso3571028qve.5 for ; Fri, 03 Dec 2021 06:15:29 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:message-id:date:mime-version:user-agent :content-language:to:cc:from:subject:content-transfer-encoding; bh=i7+L7iOwVm4sLd+qDv/L1EeBddMw0ATYWHv/PWpBdaQ=; b=hpWtGD4E5BXYcYnIKgk6PYz6wZu7jY5GJxbikMjtVbKWIhpxkaul3trluNy+ZkHEbH VAyWzd1VNK7lTdxZN5wHugb0PMW3UHcAgUKg0Hlk2oG28lxmWxksb2ZI0b7Kz4CYe0/H p3Q8aefKefn9JdmGckbEivffYPSuI9p//DyYuNuHbhs3rtTILWh59/iqGAC9aT1vGvqG vBp1GAPhm4g9kcnzqnc31pQXXQiVJlBz7DXBuwOIKAlTgKnaAP22JpACUWZiWUeyGM1q k9MycyVDiIWRNjwbmv+K+hyzJoVGRnsg2KTy6A63O7te3s5jH8jNxoRDrTcGkqFHR9Zp wcAQ== X-Gm-Message-State: AOAM530c4Bm654ld1PFmblzmycGisWIOXVwpC6eHjigkf655SKnzWxOV KBnF7fGsEHZAdsvnK6MBGW5RQ1yG8ek+lyPNSIPFXBs2T9oC6pXGy0nYMLd7CXGjPRGUEksM60b WqnxtFYBoVJTwD8vAoA== X-Received: by 2002:a05:6214:c21:: with SMTP id a1mr19675436qvd.82.1638540927942; Fri, 03 Dec 2021 06:15:27 -0800 (PST) X-Google-Smtp-Source: ABdhPJx/wkHkmkV8trFZZ4wnGPRwTGyHR8beSqLbf7YIpdWJwmgTKyTIA/bR74PrKGhrS00ywiaSUA== X-Received: by 2002:a05:6214:c21:: with SMTP id a1mr19675409qvd.82.1638540927690; Fri, 03 Dec 2021 06:15:27 -0800 (PST) Received: from ?IPV6:2607:fea8:a262:5f00::6d7? ([2607:fea8:a262:5f00::6d7]) by smtp.gmail.com with ESMTPSA id n6sm2347654qtx.88.2021.12.03.06.15.26 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Fri, 03 Dec 2021 06:15:27 -0800 (PST) Message-ID: <6ed623ba-db63-c37e-338f-ee8763fd7f4b@redhat.com> Date: Fri, 3 Dec 2021 09:15:25 -0500 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Thunderbird/91.3.2 To: Richard Biener Cc: Aldy Hernandez , gcc-patches From: Andrew MacLeod Subject: Dominators question X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Language: en-CA Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-Spam-Status: No, score=-5.7 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_H3, RCVD_IN_MSPIKE_WL, SPF_HELO_NONE, SPF_NONE, 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-patches@gcc.gnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Gcc-patches mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 03 Dec 2021 14:15:31 -0000 When something like the loop unswitching code adds elements to the CFGs, does this invalidate the dominators? or are they updated?  or is it in an in between state. Im curious because a) the relation code uses it under the covers, and b) Im looking to add a ranger caching improvement which also uses dominators if they are available. When blocks are added, I wonder what will happen to   1) dom_info_available_p (CDI_DOMINATORS)  (is it still true), and then what happens to   2) get_immediate_dominator (CDI_DOMINATORS, bb);  for one of the newly added BBs. Thanks Andrew