subvti3.c revision 276789
1/* ===-- subvti3.c - Implement __subvti3 -----------------------------------=== 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 __subvti3 for the compiler_rt library. 11 * 12 * ===----------------------------------------------------------------------=== 13 */ 14 15#include "int_lib.h" 16 17#ifdef CRT_HAS_128BIT 18 19/* Returns: a - b */ 20 21/* Effects: aborts if a - b overflows */ 22 23COMPILER_RT_ABI ti_int 24__subvti3(ti_int a, ti_int b) 25{ 26 ti_int s = (tu_int) a - (tu_int) b; 27 if (b >= 0) 28 { 29 if (s > a) 30 compilerrt_abort(); 31 } 32 else 33 { 34 if (s <= a) 35 compilerrt_abort(); 36 } 37 return s; 38} 39 40#endif /* CRT_HAS_128BIT */ 41