rt-thread/libcpu/ia32/__umodsi3.c

/*
 * Copyright (c) 2006-2021, RT-Thread Development Team
 *
 * SPDX-License-Identifier: Apache-2.0
 *
 * Change Logs:
 * Date           Author       Notes
 * 2006-10-09     Bernard      the first version for i386
 */

#include <stdint.h>

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;
}