1/* ===-- divdi3.c - Implement __divdi3 -------------------------------------===
2 *
3 *                     The LLVM Compiler Infrastructure
4 *
5 * This file is dual licensed under the MIT and the University of Illinois Open
6 * Source Licenses. See LICENSE.TXT for details.
7 *
8 * ===----------------------------------------------------------------------===
9 *
10 * This file implements __divdi3 for the compiler_rt library.
11 *
12 * ===----------------------------------------------------------------------===
13 */
14
15#include "int_lib.h"
16
17du_int COMPILER_RT_ABI __udivmoddi4(du_int a, du_int b, du_int* rem);
18
19/* Returns: a / b */
20
21COMPILER_RT_ABI di_int
22__divdi3(di_int a, di_int b)
23{
24    const int bits_in_dword_m1 = (int)(sizeof(di_int) * CHAR_BIT) - 1;
25    di_int s_a = a >> bits_in_dword_m1;           /* s_a = a < 0 ? -1 : 0 */
26    di_int s_b = b >> bits_in_dword_m1;           /* s_b = b < 0 ? -1 : 0 */
27    a = (a ^ s_a) - s_a;                         /* negate if s_a == -1 */
28    b = (b ^ s_b) - s_b;                         /* negate if s_b == -1 */
29    s_a ^= s_b;                                  /*sign of quotient */
30    return (__udivmoddi4(a, b, (du_int*)0) ^ s_a) - s_a;  /* negate if s_a == -1 */
31}
32