From mboxrd@z Thu Jan 1 00:00:00 1970 Received: with ECARTIS (v1.0.0; list linux-mips); Wed, 01 Feb 2006 09:04:16 +0000 (GMT) Received: from ns.miraclelinux.com ([219.118.163.66]:59722 "EHLO mail01.miraclelinux.com") by ftp.linux-mips.org with ESMTP id S8133654AbWBAI60 (ORCPT ); Wed, 1 Feb 2006 08:58:26 +0000 Received: from mail01 (localhost.localdomain [127.0.0.1]) by mail01.miraclelinux.com (Postfix) with ESMTP id 4559231C20D; Wed, 1 Feb 2006 18:03:26 +0900 (JST) Received: from localhost.localdomain (sshgate.miraclelinux.com []) by mail01.miraclelinux.com ([10.1.0.10]); Wed, 01 Feb 2006 09:03:26 +0000 Received: by localhost.localdomain (Postfix, from userid 1000) id D11134201E2; Wed, 1 Feb 2006 18:03:25 +0900 (JST) Message-Id: <20060201090325.696670000@localhost.localdomain> References: <20060201090224.536581000@localhost.localdomain> Date: Wed, 01 Feb 2006 18:02:37 +0900 From: Akinobu Mita To: linux-kernel@vger.kernel.org Cc: Greg Ungerer , linux-mips@linux-mips.org, sparclinux@vger.kernel.org, ultralinux@vger.kernel.org, Akinobu Mita Subject: [patch 13/44] generic ffs() Content-Disposition: inline; filename=ffs-bitops.patch Return-Path: X-Envelope-To: <"|/home/ecartis/ecartis -s linux-mips"> (uid 0) X-Orcpt: rfc822;linux-mips@linux-mips.org Original-Recipient: rfc822;linux-mips@linux-mips.org X-archive-position: 10270 X-ecartis-version: Ecartis v1.0.0 Sender: linux-mips-bounce@linux-mips.org Errors-to: linux-mips-bounce@linux-mips.org X-original-sender: mita@miraclelinux.com Precedence: bulk X-list: linux-mips This patch introduces the C-language equivalent of the function: int ffs(int x); In include/asm-generic/bitops/ffs.h This code largely copied from: include/linux/bitops.h Signed-off-by: Akinobu Mita include/asm-generic/bitops/ffs.h | 41 +++++++++++++++++++++++++++++++++++++++ 1 files changed, 41 insertions(+) Index: 2.6-git/include/asm-generic/bitops/ffs.h =================================================================== --- /dev/null +++ 2.6-git/include/asm-generic/bitops/ffs.h @@ -0,0 +1,41 @@ +#ifndef _ASM_GENERIC_BITOPS_FFS_H_ +#define _ASM_GENERIC_BITOPS_FFS_H_ + +/** + * ffs - find first bit set + * @x: the word to search + * + * This is defined the same way as + * the libc and compiler builtin ffs routines, therefore + * differs in spirit from the above ffz (man ffs). + */ +static inline int ffs(int x) +{ + int r = 1; + + if (!x) + return 0; + if (!(x & 0xffff)) { + x >>= 16; + r += 16; + } + if (!(x & 0xff)) { + x >>= 8; + r += 8; + } + if (!(x & 0xf)) { + x >>= 4; + r += 4; + } + if (!(x & 3)) { + x >>= 2; + r += 2; + } + if (!(x & 1)) { + x >>= 1; + r += 1; + } + return r; +} + +#endif /* _ASM_GENERIC_BITOPS_FFS_H_ */ -- From mboxrd@z Thu Jan 1 00:00:00 1970 From: Akinobu Mita Date: Wed, 01 Feb 2006 09:02:37 +0000 Subject: [patch 13/44] generic ffs() Message-Id: <20060201090325.696670000@localhost.localdomain> List-Id: References: <20060201090224.536581000@localhost.localdomain> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: linux-kernel@vger.kernel.org Cc: Greg Ungerer , linux-mips@linux-mips.org, sparclinux@vger.kernel.org, ultralinux@vger.kernel.org, Akinobu Mita This patch introduces the C-language equivalent of the function: int ffs(int x); In include/asm-generic/bitops/ffs.h This code largely copied from: include/linux/bitops.h Signed-off-by: Akinobu Mita include/asm-generic/bitops/ffs.h | 41 +++++++++++++++++++++++++++++++++++++++ 1 files changed, 41 insertions(+) Index: 2.6-git/include/asm-generic/bitops/ffs.h =================================--- /dev/null +++ 2.6-git/include/asm-generic/bitops/ffs.h @@ -0,0 +1,41 @@ +#ifndef _ASM_GENERIC_BITOPS_FFS_H_ +#define _ASM_GENERIC_BITOPS_FFS_H_ + +/** + * ffs - find first bit set + * @x: the word to search + * + * This is defined the same way as + * the libc and compiler builtin ffs routines, therefore + * differs in spirit from the above ffz (man ffs). + */ +static inline int ffs(int x) +{ + int r = 1; + + if (!x) + return 0; + if (!(x & 0xffff)) { + x >>= 16; + r += 16; + } + if (!(x & 0xff)) { + x >>= 8; + r += 8; + } + if (!(x & 0xf)) { + x >>= 4; + r += 4; + } + if (!(x & 3)) { + x >>= 2; + r += 2; + } + if (!(x & 1)) { + x >>= 1; + r += 1; + } + return r; +} + +#endif /* _ASM_GENERIC_BITOPS_FFS_H_ */ --