| Lionel Debieve | 6bda547 | 2020-01-02 11:09:03 +0100 | [diff] [blame] | 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 | } |