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#ifndef _LINUX_MATH64_H
#define _LINUX_MATH64_H
#include <linux/types.h>
#include <asm/div64.h>
#if BITS_PER_LONG == 64
/**
* div_u64_rem - unsigned 64bit divide with 32bit divisor with remainder
*
* This is commonly provided by 32bit archs to provide an optimized 64bit
* divide.
*/
static inline u64 div_u64_rem(u64 dividend, u32 divisor, u32 *remainder)
{
*remainder = dividend % divisor;
return dividend / divisor;
}
/**
* div_s64_rem - signed 64bit divide with 32bit divisor with remainder
*/
static inline s64 div_s64_rem(s64 dividend, s32 divisor, s32 *remainder)
{
*remainder = dividend % divisor;
return dividend / divisor;
}
/**
* div64_u64 - unsigned 64bit divide with 64bit divisor
*/
static inline u64 div64_u64(u64 dividend, u64 divisor)
{
return dividend / divisor;
}
#elif BITS_PER_LONG == 32
#ifndef div_u64_rem
static inline u64 div_u64_rem(u64 dividend, u32 divisor, u32 *remainder)
{
*remainder = do_div(dividend, divisor);
return dividend;
}
#endif
#ifndef div_s64_rem
extern s64 div_s64_rem(s64 dividend, s32 divisor, s32 *remainder);
#endif
#ifndef div64_u64
extern u64 div64_u64(u64 dividend, u64 divisor);
#endif
#endif /* BITS_PER_LONG */
/**
* div_u64 - unsigned 64bit divide with 32bit divisor
*
* This is the most common 64bit divide and should be used if possible,
* as many 32bit archs can optimize this variant better than a full 64bit
* divide.
*/
#ifndef div_u64
static inline u64 div_u64(u64 dividend, u32 divisor)
{
u32 remainder;
return div_u64_rem(dividend, divisor, &remainder);
}
#endif
/**
* div_s64 - signed 64bit divide with 32bit divisor
*/
#ifndef div_s64
static inline s64 div_s64(s64 dividend, s32 divisor)
{
s32 remainder;
return div_s64_rem(dividend, divisor, &remainder);
}
#endif
u32 iter_div_u64_rem(u64 dividend, u32 divisor, u64 *remainder);
static __always_inline u32
__iter_div_u64_rem(u64 dividend, u32 divisor, u64 *remainder)
{
u32 ret = 0;
while (dividend >= divisor) {
/* The following asm() prevents the compiler from
optimising this loop into a modulo operation. */
asm("" : "+rm"(dividend));
dividend -= divisor;
ret++;
}
*remainder = dividend;
return ret;
}
#endif /* _LINUX_MATH64_H */
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