From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 20970 invoked by alias); 13 Dec 2016 15:05:29 -0000 Mailing-List: contact libc-alpha-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: libc-alpha-owner@sourceware.org Received: (qmail 19484 invoked by uid 89); 13 Dec 2016 15:05:28 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-5.0 required=5.0 tests=BAYES_00,RP_MATCHES_RCVD,SPF_HELO_PASS autolearn=ham version=3.3.2 spammy=Hx-spam-relays-external:sk:dhcp-19, H*r:sk:dhcp-19, H*RU:sk:dhcp-19, henderson X-HELO: mx1.redhat.com Subject: Re: [PATCH][AArch64] Add more cfi annotations to tlsdesc entry points To: Richard Henderson , Szabolcs Nagy , GNU C Library References: <584AB057.5050605@arm.com> <39560805-b142-5681-4f39-096bf7045e2a@twiddle.net> Cc: nd@arm.com, Marcus Shawcroft From: Florian Weimer Message-ID: Date: Tue, 13 Dec 2016 15:05:00 -0000 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.5.1 MIME-Version: 1.0 In-Reply-To: <39560805-b142-5681-4f39-096bf7045e2a@twiddle.net> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit X-SW-Source: 2016-12/txt/msg00464.txt.bz2 On 12/09/2016 06:38 PM, Richard Henderson wrote: > On 12/09/2016 05:23 AM, Szabolcs Nagy wrote: >> stp x1, x2, [sp, #32+16*0] >> + cfi_rel_offset (x1, 32) >> + cfi_rel_offset (x2, 32+8) >> stp x3, x4, [sp, #32+16*1] >> + cfi_rel_offset (x3, 32+16) >> + cfi_rel_offset (x4, 32+24) > > FWIW, you'll produce equivalent, but smaller unwind info if you put all of the > cfi_rel_offsets together (constrained by the assembly for when the original > register values change. So > > stp x1, x2, [sp, #32+16*0] > stp x3, x4, [sp, #32+16*1] > cfi_rel_offset (x1, 32) > cfi_rel_offset (x2, 32+8) > cfi_rel_offset (x3, 32+16) > cfi_rel_offset (x4, 32+24) Will this cause problems with async cancellation? Thanks, Florian