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 888493858C2F for ; Thu, 27 Jul 2023 12:30:21 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.2 sourceware.org 888493858C2F Authentication-Results: sourceware.org; dmarc=pass (p=none dis=none) header.from=redhat.com Authentication-Results: sourceware.org; spf=pass smtp.mailfrom=redhat.com DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1690461020; h=from:from:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type:in-reply-to:in-reply-to: references:references; bh=HEZU+LYJUPJ8vCoi/YoloJTeRPe87kY69S7o4EW39xE=; b=OZytJeBJq8GerV4H2j2wf+rvcnad2OSesD11osH9iwz8JACCGAhe0BzjuAjANScxh+2ahe DC0E2QydYp4SnbHT9nZ0D7fvMddR/KYkmJVdvxaER31rm/r4Suaq924RODyyGl9t0PUWL6 ruNQt8lAXBvDqOzjXg3MUhGtcbGYOew= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-601-x8odSQaROGy1UlAlMAVTwQ-1; Thu, 27 Jul 2023 08:30:19 -0400 X-MC-Unique: x8odSQaROGy1UlAlMAVTwQ-1 Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.rdu2.redhat.com [10.11.54.7]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 66E2586F122; Thu, 27 Jul 2023 12:30:19 +0000 (UTC) Received: from tucnak.zalov.cz (unknown [10.45.224.18]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 2BDA01454145; Thu, 27 Jul 2023 12:30:19 +0000 (UTC) Received: from tucnak.zalov.cz (localhost [127.0.0.1]) by tucnak.zalov.cz (8.17.1/8.17.1) with ESMTPS id 36RCUGhb157212 (version=TLSv1.3 cipher=TLS_AES_256_GCM_SHA384 bits=256 verify=NOT); Thu, 27 Jul 2023 14:30:17 +0200 Received: (from jakub@localhost) by tucnak.zalov.cz (8.17.1/8.17.1/Submit) id 36RCUGtV157211; Thu, 27 Jul 2023 14:30:16 +0200 Date: Thu, 27 Jul 2023 14:30:15 +0200 From: Jakub Jelinek To: Richard Biener Cc: gcc-patches@gcc.gnu.org Subject: Re: [PATCH] tree-optimization/91838 - fix FAIL of g++.dg/opt/pr91838.C Message-ID: Reply-To: Jakub Jelinek References: <81140.123072708005901359@us-mta-160.us.mimecast.lan> MIME-Version: 1.0 In-Reply-To: <81140.123072708005901359@us-mta-160.us.mimecast.lan> X-Scanned-By: MIMEDefang 3.1 on 10.11.54.7 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=-3.4 required=5.0 tests=BAYES_00,DKIMWL_WL_HIGH,DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,RCVD_IN_DNSWL_NONE,RCVD_IN_MSPIKE_H4,RCVD_IN_MSPIKE_WL,SPF_HELO_NONE,SPF_NONE,TXREP,T_SCC_BODY_TEXT_LINE autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on server2.sourceware.org List-Id: On Thu, Jul 27, 2023 at 12:00:56PM +0000, Richard Biener wrote: > The following fixes the lack of simplification of a vector shift > by an out-of-bounds shift value. For scalars this is done both > by CCP and VRP but vectors are not handled there. This results > in PR91838 differences in outcome dependent on whether a vector > shift ISA is available and thus vector lowering does or does not > expose scalar shifts here. > > The following adds a match.pd pattern to catch uniform out-of-bound > shifts, simplifying them to zero when not sanitizing shift amounts. > > Bootstrapped and tested on x86_64-unknown-linux-gnu. > > OK? > > Thanks, > Richard. > > PR tree-optimization/91838 > * match.pd (([rl]shift @0 out-of-bounds) -> zero): New pattern. The !(flag_sanitize & SANITIZE_SHIFT_EXPONENT) should be !sanitize_flags_p (SANITIZE_SHIFT_EXPONENT) or maybe even GIMPLE || !sanitize_flags_p (SANITIZE_SHIFT_EXPONENT) because the shift ubsan instrumentation is done on GENERIC, so it can be optimized on GIMPLE even with ubsan. Otherwise LGTM. Jakub