From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 27961 invoked by alias); 15 Apr 2016 07:43:35 -0000 Mailing-List: contact gcc-patches-help@gcc.gnu.org; run by ezmlm Precedence: bulk List-Id: List-Archive: List-Post: List-Help: Sender: gcc-patches-owner@gcc.gnu.org Received: (qmail 27944 invoked by uid 89); 15 Apr 2016 07:43:34 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-0.8 required=5.0 tests=AWL,BAYES_00,KAM_LAZY_DOMAIN_SECURITY,RCVD_IN_DNSWL_NONE autolearn=no version=3.3.2 spammy=krebbellinuxvnetibmcom, krebbel@linux.vnet.ibm.com, sk:krebbel, U*krebbel X-HELO: smtp.eu.adacore.com Received: from mel.act-europe.fr (HELO smtp.eu.adacore.com) (194.98.77.210) by sourceware.org (qpsmtpd/0.93/v0.84-503-g423c35a) with (AES256-GCM-SHA384 encrypted) ESMTPS; Fri, 15 Apr 2016 07:43:33 +0000 Received: from localhost (localhost [127.0.0.1]) by filtered-smtp.eu.adacore.com (Postfix) with ESMTP id A85B6812EA; Fri, 15 Apr 2016 09:43:29 +0200 (CEST) Received: from smtp.eu.adacore.com ([127.0.0.1]) by localhost (smtp.eu.adacore.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id ZkYNv03R4pbQ; Fri, 15 Apr 2016 09:43:29 +0200 (CEST) Received: from idefix.act-europe.fr (idefix.act-europe.fr [10.10.1.101]) (using TLSv1 with cipher ECDHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by smtp.eu.adacore.com (Postfix) with ESMTPSA id 7CABC81329; Fri, 15 Apr 2016 09:43:28 +0200 (CEST) Content-Type: text/plain; charset=windows-1252 Mime-Version: 1.0 (Mac OS X Mail 8.2 \(2104\)) Subject: Re: rs6000 stack_tie mishap again From: Olivier Hainque In-Reply-To: <5710701B.9070101@linux.vnet.ibm.com> Date: Fri, 15 Apr 2016 07:43:00 -0000 Cc: Olivier Hainque , Jeff Law , Alan Modra , GCC Patches , Richard Henderson , Segher Boessenkool , uweigand@de.ibm.com Content-Transfer-Encoding: quoted-printable Message-Id: <7895F694-76DD-4507-8D45-2B0A47B52C86@adacore.com> References: <20160324041034.GB31470@bubble.grove.modra.org> <56F96CE2.9020001@redhat.com> <888A9BC7-458D-46DE-BEC1-8AC000C6849D@adacore.com> <570FBB7C.7060802@linux.vnet.ibm.com> <570FCA3B.2070001@redhat.com> <5710701B.9070101@linux.vnet.ibm.com> To: Andreas Krebbel X-SW-Source: 2016-04/txt/msg00701.txt.bz2 > On Apr 15, 2016, at 06:37 , Andreas Krebbel = wrote: >> /* (mem:BLK (scratch)) is a special mechanism to conflict with everythi= ng. >> This is used in epilogue deallocation functions. */ >> ... >=20 > Ok thanks. I've verified that the dependencies are also generated when > using this expression in a clobber. Ok, thanks. This is consistent with what I've seen. >> sequence was allowed to move past the stack pointer reset when >> it's performed as a mere register to register move. >=20 > I've seen the same on S/390 when restoring the stack pointer > from a floating point reg. But I think it is not limited to > reg-reg stack pointer restores. Potentially this could also > happen with the stack pointer decrement in the prologue which > could also get moved across a mem only barrier. Indeed. With Kind Regards, Olivier