From patchwork Mon Oct 27 07:59:42 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andrew Pinski X-Patchwork-Id: 3412 Received: (qmail 15949 invoked by alias); 27 Oct 2014 08:00:18 -0000 Mailing-List: contact libc-alpha-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Unsubscribe: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: libc-alpha-owner@sourceware.org Delivered-To: mailing list libc-alpha@sourceware.org Received: (qmail 15448 invoked by uid 89); 27 Oct 2014 08:00:02 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-2.6 required=5.0 tests=AWL, BAYES_00, RCVD_IN_DNSWL_LOW autolearn=ham version=3.3.2 X-HELO: mail-ie0-f178.google.com X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references; bh=Zrqw6bLXh5kxubrSX26E2rNOYUz1WYSL568TPf2mej0=; b=RmuhV/D1l2jCOSqTlRM5Vh3s/ovWRbfE9EMOrzTCvCZ0/nVXcQxBrOxOV3+n6txLk6 ySFMHm/+KyMgAGeDWb8KsCkZbTnbZ72MgPVJsvmpoxsKer86QpwlHrnz65j4UxrPrj79 74XvthkWiv5PdKX+3X1DMa1+dxapZurZj7POSxSBOybgH+TuKa5O/MPRWp48CV9/tJ9x BGWcHaT4PNvJKED1XdaeUvU9gthqjXVxQNWuEuw3AB75ORk21K4l/DelhTcBZ02efWVy eIoFVdJzX5Xl7R7Adjr6qZE4TliLdTMk39rC3GSefrT64p1KdFv4WPDXg/rktiqTouzO /4vg== X-Gm-Message-State: ALoCoQkLUM5rXpbVYFvDXQ1MMbbQAclXHnjELcZt1UiX4qs1ienq5OXErPmJhQtQEoRNSjiGg5x0 X-Received: by 10.42.114.18 with SMTP id e18mr18008035icq.42.1414396799815; Mon, 27 Oct 2014 00:59:59 -0700 (PDT) From: Andrew Pinski To: libc-alpha@sourceware.org Cc: Andrew Pinski Subject: [PATCH 18/29] [AARCH64] Reformat inline-asm in elf_machine_load_address. Date: Mon, 27 Oct 2014 00:59:42 -0700 Message-Id: <1414396793-9005-19-git-send-email-apinski@cavium.com> In-Reply-To: <1414396793-9005-1-git-send-email-apinski@cavium.com> References: <1414396793-9005-1-git-send-email-apinski@cavium.com> This patch reformats the inline-asm in elf_machine_load_address so it is easier to change only part of the inline-asm. That is using string concating instead of string continueing. Also document on why this inline-asm works, it depends on the 32bit relocation being resolved at link time. * sysdeps/aarch64/dl-machine.h (elf_machine_load_address): Refactor inline-asm. Also add comment. --- sysdeps/aarch64/dl-machine.h | 21 ++++++++++++--------- 1 files changed, 12 insertions(+), 9 deletions(-) diff --git a/sysdeps/aarch64/dl-machine.h b/sysdeps/aarch64/dl-machine.h index 6e041b1..121b178 100644 --- a/sysdeps/aarch64/dl-machine.h +++ b/sysdeps/aarch64/dl-machine.h @@ -53,19 +53,22 @@ elf_machine_load_address (void) The choice of symbol is arbitrary. The static address we obtain by constructing a non GOT reference to the symbol, the dynamic address of the symbol we compute using adrp/add to compute the - symbol's address relative to the PC. */ + symbol's address relative to the PC. + This depends on 32bit relocations being resolved at link time + and that the static address fits in the 32bits. */ ElfW(Addr) static_addr; ElfW(Addr) dynamic_addr; - asm (" \n\ - adrp %1, _dl_start; \n\ - add %1, %1, #:lo12:_dl_start \n\ - ldr %w0, 1f \n\ - b 2f \n\ -1: .word _dl_start \n\ -2: \n\ - " : "=r" (static_addr), "=r" (dynamic_addr)); + asm (" \n" +" adrp %1, _dl_start; \n" +" add %1, %1, #:lo12:_dl_start \n" +" ldr %w0, 1f \n" +" b 2f \n" +"1: \n" +" .word _dl_start \n" +"2: \n" + : "=r" (static_addr), "=r" (dynamic_addr)); return dynamic_addr - static_addr; }