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#ifndef _ASM_X86_DIV64_H
#define _ASM_X86_DIV64_H
#ifdef CONFIG_X86_32
#include <linux/types.h>
/*
* do_div() is NOT a C function. It wants to return
* two values (the quotient and the remainder), but
* since that doesn't work very well in C, what it
* does is:
*
* - modifies the 64-bit dividend _in_place_
* - returns the 32-bit remainder
*
* This ends up being the most efficient "calling
* convention" on x86.
*/
#define do_div(n, base) \
({ \
unsigned long __upper, __low, __high, __mod, __base; \
__base = (base); \
asm("":"=a" (__low), "=d" (__high) : "A" (n)); \
__upper = __high; \
if (__high) { \
__upper = __high % (__base); \
__high = __high / (__base); \
} \
asm("divl %2":"=a" (__low), "=d" (__mod) \
: "rm" (__base), "0" (__low), "1" (__upper)); \
asm("":"=A" (n) : "a" (__low), "d" (__high)); \
__mod; \
})
/*
* (long)X = ((long long)divs) / (long)div
* (long)rem = ((long long)divs) % (long)div
*
* Warning, this will do an exception if X overflows.
*/
#define div_long_long_rem(a, b, c) div_ll_X_l_rem(a, b, c)
static inline long div_ll_X_l_rem(long long divs, long div, long *rem)
{
long dum2;
asm("divl %2":"=a"(dum2), "=d"(*rem)
: "rm"(div), "A"(divs));
return dum2;
}
extern uint64_t div64_64(uint64_t dividend, uint64_t divisor);
#else
# include <asm-generic/div64.h>
#endif /* CONFIG_X86_32 */
#endif /* _ASM_X86_DIV64_H */
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