You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
49 lines
1.1 KiB
49 lines
1.1 KiB
20 years ago
|
#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
|