diff options
Diffstat (limited to 'lib/clz_ctz.c')
| -rw-r--r-- | lib/clz_ctz.c | 43 |
1 files changed, 14 insertions, 29 deletions
diff --git a/lib/clz_ctz.c b/lib/clz_ctz.c index a8f8379eb49f..8778ec44bf63 100644 --- a/lib/clz_ctz.c +++ b/lib/clz_ctz.c @@ -1,11 +1,12 @@ +// SPDX-License-Identifier: GPL-2.0-only /* * lib/clz_ctz.c * * Copyright (C) 2013 Chanho Min <chanho.min@lge.com> * - * 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. + * The functions in this file aren't called directly, but are required by + * GCC builtins such as __builtin_ctz, and therefore they can't be removed + * despite appearing unreferenced in kernel source. * * __c[lt]z[sd]i2 can be overridden by linking arch-specific versions. */ @@ -13,46 +14,30 @@ #include <linux/export.h> #include <linux/kernel.h> -int __weak __ctzsi2(int val) +int __weak __ctzsi2(int val); +int __weak __attribute_const__ __ctzsi2(int val) { return __ffs(val); } EXPORT_SYMBOL(__ctzsi2); -int __weak __clzsi2(int val) +int __weak __clzsi2(int val); +int __weak __attribute_const__ __clzsi2(int val) { return 32 - fls(val); } EXPORT_SYMBOL(__clzsi2); -#if BITS_PER_LONG == 32 - -int __weak __clzdi2(long val) +int __weak __clzdi2(u64 val); +int __weak __attribute_const__ __clzdi2(u64 val) { - return 32 - fls((int)val); + return 64 - fls64(val); } EXPORT_SYMBOL(__clzdi2); -int __weak __ctzdi2(long val) +int __weak __ctzdi2(u64 val); +int __weak __attribute_const__ __ctzdi2(u64 val) { - return __ffs((u32)val); + return __ffs64(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 |