From patchwork Thu May 2 09:56:19 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Chanho Min X-Patchwork-Id: 240930 X-Patchwork-Delegate: davem@davemloft.net Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 1AA632C00CD for ; Thu, 2 May 2013 19:57:02 +1000 (EST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754674Ab3EBJ4r (ORCPT ); Thu, 2 May 2013 05:56:47 -0400 Received: from LGEMRELSE6Q.lge.com ([156.147.1.121]:51012 "EHLO LGEMRELSE6Q.lge.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751545Ab3EBJ4q (ORCPT ); Thu, 2 May 2013 05:56:46 -0400 X-AuditID: 9c930179-b7c28ae0000018a0-1d-51823859845a Received: from localhost.localdomain ( [10.178.36.63]) by LGEMRELSE6Q.lge.com (Symantec Brightmail Gateway) with SMTP id 57.9A.06304.95832815; Thu, 2 May 2013 18:56:42 +0900 (KST) From: Chanho Min To: Andrew Morton Cc: Kyungsik Lee , Yann Collet , Bob Pearson , Richard Weinberger , Geert Uytterhoeven , linux-kernel@vger.kernel.org, sparclinux@vger.kernel.org, linux-m68k@vger.kernel.org, linux-next@vger.kernel.org, Chanho Min Subject: [PATCH] lib: add weak clz/ctz functions Date: Thu, 2 May 2013 18:56:19 +0900 Message-Id: <1367488579-15456-1-git-send-email-chanho.min@lge.com> X-Mailer: git-send-email 1.7.9.5 X-Brightmail-Tracker: AAAAAA== Sender: sparclinux-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: sparclinux@vger.kernel.org Some architectures need __c[lt]z[sd]i2() for __builtin_c[lt]z[ll] and It causes build failure. They can be implemented using the fls()/__ffs() and overridden by linking arch-specific versions may not be implemented yet. Reference: https://lkml.org/lkml/2013/4/18/603 Reported-by: Geert Uytterhoeven Signed-off-by: Chanho Min --- lib/Makefile | 2 +- lib/clz_ctz.c | 58 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 59 insertions(+), 1 deletion(-) create mode 100644 lib/clz_ctz.c diff --git a/lib/Makefile b/lib/Makefile index af79e8c..3eacb2c 100644 --- a/lib/Makefile +++ b/lib/Makefile @@ -23,7 +23,7 @@ lib-y += kobject.o klist.o obj-y += bcd.o div64.o sort.o parser.o halfmd4.o debug_locks.o random32.o \ bust_spinlocks.o hexdump.o kasprintf.o bitmap.o scatterlist.o \ - gcd.o lcm.o list_sort.o uuid.o flex_array.o \ + gcd.o lcm.o list_sort.o uuid.o flex_array.o clz_ctz.o\ bsearch.o find_last_bit.o find_next_bit.o llist.o memweight.o kfifo.o obj-y += string_helpers.o obj-$(CONFIG_TEST_STRING_HELPERS) += test-string_helpers.o diff --git a/lib/clz_ctz.c b/lib/clz_ctz.c new file mode 100644 index 0000000..a8f8379 --- /dev/null +++ b/lib/clz_ctz.c @@ -0,0 +1,58 @@ +/* + * lib/clz_ctz.c + * + * Copyright (C) 2013 Chanho Min + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * __c[lt]z[sd]i2 can be overridden by linking arch-specific versions. + */ + +#include +#include + +int __weak __ctzsi2(int val) +{ + return __ffs(val); +} +EXPORT_SYMBOL(__ctzsi2); + +int __weak __clzsi2(int val) +{ + return 32 - fls(val); +} +EXPORT_SYMBOL(__clzsi2); + +#if BITS_PER_LONG == 32 + +int __weak __clzdi2(long val) +{ + return 32 - fls((int)val); +} +EXPORT_SYMBOL(__clzdi2); + +int __weak __ctzdi2(long val) +{ + return __ffs((u32)val); +} +EXPORT_SYMBOL(__ctzdi2); + +#elif BITS_PER_LONG == 64 + +int __weak __clzdi2(long val) +{ + return 64 - fls64((u64)val); +} +EXPORT_SYMBOL(__clzdi2); + +int __weak __ctzdi2(long val) +{ + return __ffs64((u64)val); +} +EXPORT_SYMBOL(__ctzdi2); + +#else +#error BITS_PER_LONG not 32 or 64 +#endif