1 | /*===-- moddi3.c - Implement __moddi3 -------------------------------------=== |
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 __moddi3 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 | __moddi3(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 = b >> bits_in_dword_m1; /* s = b < 0 ? -1 : 0 */ |
24 | b = (b ^ s) - s; /* negate if s == -1 */ |
25 | s = a >> bits_in_dword_m1; /* s = a < 0 ? -1 : 0 */ |
26 | a = (a ^ s) - s; /* negate if s == -1 */ |
27 | du_int r; |
28 | __udivmoddi4(a, b, &r); |
29 | return ((di_int)r ^ s) - s; /* negate if s == -1 */ |
30 | } |
31 | |