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 | |