/* * 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. * 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. */ #include #include int __weak __ctzsi2(int val); int __weak __ctzsi2(int val) { return __ffs(val); } int __weak __clzsi2(int val); int __weak __clzsi2(int val) { return 32 - fls(val); } int __weak __clzdi2(long val); int __weak __ctzdi2(long val); #if BITS_PER_LONG == 32 int __weak __clzdi2(long val) { return 32 - fls((int)val); } int __weak __ctzdi2(long val) { return __ffs((u32)val); } #elif BITS_PER_LONG == 64 int __weak __clzdi2(long val) { return 64 - fls64((u64)val); } int __weak __ctzdi2(long val) { return __ffs64((u64)val); } #else #error BITS_PER_LONG not 32 or 64 #endif