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      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 
     17 /* Returns: a / b */
     18 
     19 COMPILER_RT_ABI di_int
     20 __divdi3(di_int a, di_int b)
     21 {
     22     const int bits_in_dword_m1 = (int)(sizeof(di_int) * CHAR_BIT) - 1;
     23     di_int s_a = a >> bits_in_dword_m1;           /* s_a = a < 0 ? -1 : 0 */
     24     di_int s_b = b >> bits_in_dword_m1;           /* s_b = b < 0 ? -1 : 0 */
     25     a = (a ^ s_a) - s_a;                         /* negate if s_a == -1 */
     26     b = (b ^ s_b) - s_b;                         /* negate if s_b == -1 */
     27     s_a ^= s_b;                                  /*sign of quotient */
     28     return (__udivmoddi4(a, b, (du_int*)0) ^ s_a) - s_a;  /* negate if s_a == -1 */
     29 }
     30