From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 6451 invoked by alias); 29 Apr 2015 10:58:58 -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 5544 invoked by uid 89); 29 Apr 2015 10:58:57 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-2.4 required=5.0 tests=AWL,BAYES_00,FREEMAIL_FROM,RCVD_IN_DNSWL_LOW,SPF_PASS autolearn=ham version=3.3.2 X-HELO: mail-wi0-f178.google.com Received: from mail-wi0-f178.google.com (HELO mail-wi0-f178.google.com) (209.85.212.178) by sourceware.org (qpsmtpd/0.93/v0.84-503-g423c35a) with (AES128-GCM-SHA256 encrypted) ESMTPS; Wed, 29 Apr 2015 10:58:56 +0000 Received: by wizk4 with SMTP id k4so175107596wiz.1 for ; Wed, 29 Apr 2015 03:58:53 -0700 (PDT) MIME-Version: 1.0 X-Received: by 10.194.9.161 with SMTP id a1mr41256737wjb.39.1430305133794; Wed, 29 Apr 2015 03:58:53 -0700 (PDT) Received: by 10.28.104.138 with HTTP; Wed, 29 Apr 2015 03:58:53 -0700 (PDT) In-Reply-To: References: <54900732.4010604@arm.com> Date: Wed, 29 Apr 2015 11:14:00 -0000 Message-ID: Subject: Re: [PATCH][AARCH64]Add ACLE 2.0 predefined macros: __ARM_ALIGN_MAX_PWR and __ARM_ALIGN_MAX_STACK_PWR From: Marcus Shawcroft To: Renlin Li Cc: "gcc-patches@gcc.gnu.org" , marcus Shawcroft , ramana Radhakrishnan , Andrew Pinski Content-Type: text/plain; charset=UTF-8 X-IsSubscribed: yes X-SW-Source: 2015-04/txt/msg01857.txt.bz2 On 29 April 2015 at 01:24, Andrew Pinski wrote: > On Tue, Dec 16, 2014 at 2:19 AM, Renlin Li wrote: >> Hi all, >> >> This is a simple patch to add another two ACLE 2.0 predefined macros into >> aarch64 backend. >> They are __ARM_ALIGN_MAX_PWR and __ARM_ALIGN_MAX_STACK_PWR. Currently, those >> two values are hard-wired to 16. >> >> The following clauses from ACLE 2.0 documentation indicate the meaning of >> those two macros: >> >> The macro __ARM_ALIGN_MAX_STACK_PWR indicates (as the exponent of a power of >> 2) the maximum available stack alignment. >> The macro __ARM_ALIGN_MAX_PWR indicates (as the exponent of a power of 2) >> the maximum available alignment of static data. >> >> aarch64-none-elf target is tested on on the model. No new regression. >> >> Is it Okay for trunk? > > Have you tested these alignments? That is have we tested 65536 > alignment for both stack and static data? > I suspect the stack alignment that is support is not 64k but much > smaller. And the supported static data alignment is much larger, > maybe 20 or more. Looks to me __ARM_ALIGN_MAX_STACK_PWR can be lifted to 2^16 without issue. GCC won't gripe about the static data alignment until 2^29. Aside from the latter being rather conservative I think we should add a test case to the testsuite for each. RenLin can you prep a testcase? /Marcus