blob: 516751d1221759e8754dc5fcb48a5795cc05d1d5 [file] [log] [blame]
/*
* 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.
*/
#include <linux/export.h>
#include <linux/kernel.h>
int __visible __ctzsi2(int val);
int __visible __ctzsi2(int val)
{
return __ffs(val);
}
EXPORT_SYMBOL(__ctzsi2);
int __visible __clzsi2(int val);
int __visible __clzsi2(int val)
{
return 32 - fls(val);
}
EXPORT_SYMBOL(__clzsi2);
int __visible __clzdi2(long val);
int __visible __ctzdi2(long val);
#if BITS_PER_LONG == 32
int __visible __clzdi2(long val)
{
return 32 - fls((int)val);
}
EXPORT_SYMBOL(__clzdi2);
int __visible __ctzdi2(long val)
{
return __ffs((u32)val);
}
EXPORT_SYMBOL(__ctzdi2);
#elif BITS_PER_LONG == 64
int __visible __clzdi2(long val)
{
return 64 - fls64((u64)val);
}
EXPORT_SYMBOL(__clzdi2);
int __visible __ctzdi2(long val)
{
return __ffs64((u64)val);
}
EXPORT_SYMBOL(__ctzdi2);
#else
#error BITS_PER_LONG not 32 or 64
#endif