| Daniel Dunbar | b3a6901 | 2009-06-26 16:47:03 +0000 | [diff] [blame^] | 1 | //===-- subvti3.c - Implement __subvti3 -----------------------------------===// |
| 2 | // |
| 3 | // The LLVM Compiler Infrastructure |
| 4 | // |
| 5 | // This file is distributed under the University of Illinois Open Source |
| 6 | // License. See LICENSE.TXT for details. |
| 7 | // |
| 8 | //===----------------------------------------------------------------------===// |
| 9 | // |
| 10 | // This file implements __subvti3 for the compiler_rt library. |
| 11 | // |
| 12 | //===----------------------------------------------------------------------===// |
| 13 | |
| 14 | #if __x86_64 |
| 15 | |
| 16 | #include "int_lib.h" |
| 17 | #include <stdlib.h> |
| 18 | |
| 19 | // Returns: a - b |
| 20 | |
| 21 | // Effects: aborts if a - b overflows |
| 22 | |
| 23 | ti_int |
| 24 | __subvti3(ti_int a, ti_int b) |
| 25 | { |
| 26 | ti_int s = a - b; |
| 27 | if (b >= 0) |
| 28 | { |
| 29 | if (s > a) |
| 30 | abort(); |
| 31 | } |
| 32 | else |
| 33 | { |
| 34 | if (s <= a) |
| 35 | abort(); |
| 36 | } |
| 37 | return s; |
| 38 | } |
| 39 | |
| 40 | #endif |