From patchwork Wed Dec 18 07:32:45 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kuninori Morimoto X-Patchwork-Id: 11299659 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 75AEC1593 for ; Wed, 18 Dec 2019 07:32:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 5DCCF21582 for ; Wed, 18 Dec 2019 07:32:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726497AbfLRHcr (ORCPT ); Wed, 18 Dec 2019 02:32:47 -0500 Received: from relmlor1.renesas.com ([210.160.252.171]:47248 "EHLO relmlie5.idc.renesas.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726454AbfLRHcq (ORCPT ); Wed, 18 Dec 2019 02:32:46 -0500 Date: 18 Dec 2019 16:32:45 +0900 X-IronPort-AV: E=Sophos;i="5.69,328,1571670000"; d="scan'208";a="34736284" Received: from unknown (HELO relmlir5.idc.renesas.com) ([10.200.68.151]) by relmlie5.idc.renesas.com with ESMTP; 18 Dec 2019 16:32:45 +0900 Received: from morimoto-PC.renesas.com (unknown [10.166.18.140]) by relmlir5.idc.renesas.com (Postfix) with ESMTP id C5D22400D4EA; Wed, 18 Dec 2019 16:32:45 +0900 (JST) Message-ID: <871rt2jdgi.wl-kuninori.morimoto.gx@renesas.com> From: Kuninori Morimoto Subject: [PATCH] sh: use generic strncpy() User-Agent: Wanderlust/2.15.9 Emacs/24.5 Mule/6.0 To: Yoshinori Sato , Rich Felker , Karl Nasrallah Cc: Linux-SH , Linux-Renesas In-Reply-To: <8736dijdit.wl-kuninori.morimoto.gx@renesas.com> References: <8736dijdit.wl-kuninori.morimoto.gx@renesas.com> MIME-Version: 1.0 (generated by SEMI-EPG 1.14.7 - "Harue") Sender: linux-sh-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-sh@vger.kernel.org From: Karl Nasrallah Current SH will get below warning at strncpy() In file included from ${LINUX}/arch/sh/include/asm/string.h:3, from ${LINUX}/include/linux/string.h:20, from ${LINUX}/include/linux/bitmap.h:9, from ${LINUX}/include/linux/nodemask.h:95, from ${LINUX}/include/linux/mmzone.h:17, from ${LINUX}/include/linux/gfp.h:6, from ${LINUX}/innclude/linux/slab.h:15, from ${LINUX}/linux/drivers/mmc/host/vub300.c:38: ${LINUX}/drivers/mmc/host/vub300.c: In function 'new_system_port_status': ${LINUX}/arch/sh/include/asm/string_32.h:51:42: warning: array subscript\ 80 is above array bounds of 'char[26]' [-Warray-bounds] : "0" (__dest), "1" (__src), "r" (__src+__n) ~~~~~^~~~ This patch fixup it Signed-off-by: Karl Nasrallah Signed-off-by: Kuninori Morimoto --- This is Karl's 1st pattern arch/sh/include/asm/string_32.h | 54 ++++++++++++++++++++++++++--------------- 1 file changed, 35 insertions(+), 19 deletions(-) diff --git a/arch/sh/include/asm/string_32.h b/arch/sh/include/asm/string_32.h index 3558b1d..d35b92f 100644 --- a/arch/sh/include/asm/string_32.h +++ b/arch/sh/include/asm/string_32.h @@ -31,27 +31,43 @@ static inline char *strcpy(char *__dest, const char *__src) #define __HAVE_ARCH_STRNCPY static inline char *strncpy(char *__dest, const char *__src, size_t __n) { - register char *__xdest = __dest; - unsigned long __dummy; + char * retval = __dest; + const char * __dest_end = __dest + __n - 1; + register unsigned int * r0_register __asm__ ("r0"); + /* size_t is always unsigned */ if (__n == 0) - return __xdest; - - __asm__ __volatile__( - "1:\n" - "mov.b @%1+, %2\n\t" - "mov.b %2, @%0\n\t" - "cmp/eq #0, %2\n\t" - "bt/s 2f\n\t" - " cmp/eq %5,%1\n\t" - "bf/s 1b\n\t" - " add #1, %0\n" - "2:" - : "=r" (__dest), "=r" (__src), "=&z" (__dummy) - : "0" (__dest), "1" (__src), "r" (__src+__n) - : "memory", "t"); - - return __xdest; + return retval; + + /* + * Some notes: + * - cmp/eq #imm8,r0 is its own instruction + * - incrementing dest and comparing to dest_end handles the size parameter in only one instruction + * - mov.b R0,@Rn+ is SH2A only, but we can fill a delay slot with "add #1,%[dest]" + */ + __asm__ __volatile__ ( + "strncpy_start:\n\t" + "mov.b @%[src]+,%[r0_reg]\n\t" + "cmp/eq #0,%[r0_reg]\n\t" + "bt.s strncpy_pad\n\t" + "cmp/eq %[dest],%[dest_end]\n\t" + "bt.s strncpy_end\n\t" + "mov.b %[r0_reg],@%[dest]\n\t" + "bra strncpy_start\n\t" + "add #1,%[dest]\n\t" + "strncpy_pad:\n\t" + "bt.s strncpy_end\n\t" + "mov.b %[r0_reg],@%[dest]\n\t" + "add #1,%[dest]\n\t" + "bra strncpy_pad\n\t" + "cmp/eq %[dest],%[dest_end]\n\t" + "strncpy_end:\n\t" + : [src] "+r" (__src), [dest] "+r" (__dest), [r0_reg] "+&z" (r0_register) + : [dest_end] "r" (__dest_end) + : "t","memory" + ); + + return retval; } #define __HAVE_ARCH_STRCMP