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 [63.128.21.124]) by sourceware.org (Postfix) with ESMTP id 42EBD3858038 for ; Mon, 4 Jan 2021 21:13:09 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.3.2 sourceware.org 42EBD3858038 Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-466-Yi1ZrInWOfmdHLMGOUyjJw-1; Mon, 04 Jan 2021 16:13:07 -0500 X-MC-Unique: Yi1ZrInWOfmdHLMGOUyjJw-1 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 7B3831927801; Mon, 4 Jan 2021 21:13:06 +0000 (UTC) Received: from localhost.localdomain (ovpn-114-95.phx2.redhat.com [10.3.114.95]) by smtp.corp.redhat.com (Postfix) with ESMTP id 0FD0760BE5; Mon, 4 Jan 2021 21:13:05 +0000 (UTC) Subject: Re: [PATCH] rtl-ssa: Fix updates to call clobbers [PR98403] To: gcc-patches@gcc.gnu.org, richard.sandiford@arm.com References: From: Jeff Law Message-ID: <695fd678-7310-30eb-b208-2412c498e803@redhat.com> Date: Mon, 4 Jan 2021 14:13:05 -0700 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.6.0 MIME-Version: 1.0 In-Reply-To: X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Content-Language: en-US X-Spam-Status: No, score=-5.8 required=5.0 tests=BAYES_00, DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, DKIM_VALID_EF, NICE_REPLY_A, RCVD_IN_DNSWL_LOW, RCVD_IN_MSPIKE_H4, RCVD_IN_MSPIKE_WL, SPF_HELO_NONE, SPF_PASS, TXREP autolearn=ham autolearn_force=no version=3.4.2 X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) 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: Mon, 04 Jan 2021 21:13:10 -0000 On 12/21/20 9:32 AM, Richard Sandiford wrote: > In the PR, fwprop was changing a call instruction and tripped > an assert when trying to update a list of call clobbers. > There are two ways we could handle this: remove the call clobber > and then add it back, or assume that the clobber will stay in its > current place. > > At the moment we don't have enough information to safely move > calls around, so the second approach seems simpler and more > efficient. > > Tested on x86_64-linux-gnu and aarch64-linux-gnu. OK to install? > > Richard > > > gcc/ > PR rtl-optimization/98403 > * rtl-ssa/changes.cc (function_info::finalize_new_accesses): Explain > why we don't remove call clobbers. > (function_info::apply_changes_to_insn): Don't attempt to add > call clobbers here. > > gcc/testsuite/ > PR rtl-optimization/98403 > * g++.dg/opt/pr98403.C: New test. OK jeff