div64.h
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#ifndef _ASM_GENERIC_DIV64_H
#define _ASM_GENERIC_DIV64_H
/*
* Copyright (C) 2003 Bernardo Innocenti <bernie@develer.com>
* Based on former asm-ppc/div64.h and asm-m68knommu/div64.h
*
* The semantics of do_div() are:
*
* uint32_t do_div(uint64_t *n, uint32_t base)
* {
* uint32_t remainder = *n % base;
* *n = *n / base;
* return remainder;
* }
*
* NOTE: macro parameter n is evaluated multiple times,
* beware of side effects!
*/
#include <linux/types.h>
extern uint32_t __div64_32(uint64_t *dividend, uint32_t divisor);
/* The unnecessary pointer compare is there
* to check for type safety (n must be 64bit)
*/
# define do_div(n,base) ({ \
uint32_t __base = (base); \
uint32_t __rem; \
(void)(((typeof((n)) *)0) == ((uint64_t *)0)); \
if (((n) >> 32) == 0) { \
__rem = (uint32_t)(n) % __base; \
(n) = (uint32_t)(n) / __base; \
} else \
__rem = __div64_32(&(n), __base); \
__rem; \
})
/* Wrapper for do_div(). Doesn't modify dividend and returns
* the result, not reminder.
*/
static inline uint64_t lldiv(uint64_t dividend, uint32_t divisor)
{
uint64_t __res = dividend;
do_div(__res, divisor);
return(__res);
}
#endif /* _ASM_GENERIC_DIV64_H */