__udivmoddi4.c

来自「klibc精简化的c程序库」· C语言 代码 · 共 33 行

#include <klibc/diverr.h>
#include <stdint.h>

uint64_t __udivmoddi4(uint64_t num, uint64_t den, uint64_t * rem_p)
{
	uint64_t quot = 0, qbit = 1;

	if (den == 0) {
		__divide_error();
		return 0;	/* If trap returns... */
	}

	/* Left-justify denominator and count shift */
	while ((int64_t) den >= 0) {
		den <<= 1;
		qbit <<= 1;
	}

	while (qbit) {
		if (den <= num) {
			num -= den;
			quot += qbit;
		}
		den >>= 1;
		qbit >>= 1;
	}

	if (rem_p)
		*rem_p = num;

	return quot;
}