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#ifndef __ASM_ARM_DIV64
#define __ASM_ARM_DIV64
#include <asm/system.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;
* }
*
* In other words, a 64-bit dividend with a 32-bit divisor producing
* a 64-bit result and a 32-bit remainder. To accomplish this optimally
* we call a special __do_div64 helper with completely non standard
* calling convention for arguments and results (beware).
*/
#ifdef __ARMEB__
#define __xh "r0"
#define __xl "r1"
#else
#define __xl "r0"
#define __xh "r1"
#endif
#define do_div(n,base) \
({ \
register unsigned int __base asm("r4") = base; \
register unsigned long long __n asm("r0") = n; \
register unsigned long long __res asm("r2"); \
register unsigned int __rem asm(__xh); \
asm( __asmeq("%0", __xh) \
__asmeq("%1", "r2") \
__asmeq("%2", "r0") \
__asmeq("%3", "r4") \
"bl __do_div64" \
: "=r" (__rem), "=r" (__res) \
: "r" (__n), "r" (__base) \
: "ip", "lr", "cc"); \
n = __res; \
__rem; \
})
#endif
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