rt-thread-official/libcpu/ia32/__umodsi3.c

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/*
* File : __umodsi3.c
* This file is part of RT-Thread RTOS
* COPYRIGHT (C) 2006, RT-Thread Develop Team
*
* The license and distribution terms for this file may be
* found in the file LICENSE in this distribution or at
* http://openlab.rt-thread.com/license/LICENSE
*
* Change Logs:
* Date Author Notes
* 2006-10-09 Bernard the first version for i386
*/
#include <rtthread.h>
typedef rt_uint32_t uint32_t;
typedef rt_int32 int32_t;
uint32_t __umodsi3(uint32_t num, uint32_t den)
{
register uint32_t quot = 0, qbit = 1;
if (den == 0)
{
asm volatile ("int $0");
return 0; /* if trap returns... */
}
/* left-justify denominator and count shift */
while ((int32_t) den >= 0)
{
den <<= 1;
qbit <<= 1;
}
while (qbit)
{
if (den <= num)
{
num -= den;
quot += qbit;
}
den >>= 1;
qbit >>= 1;
}
return num;
}