1 //===-- subvti3.c - Implement __subvti3 -----------------------------------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 //
9 // This file implements __subvti3 for the compiler_rt library.
10 //
11 //===----------------------------------------------------------------------===//
12 
13 #include "int_lib.h"
14 
15 #ifdef CRT_HAS_128BIT
16 
17 // Returns: a - b
18 
19 // Effects: aborts if a - b overflows
20 
21 COMPILER_RT_ABI ti_int __subvti3(ti_int a, ti_int b) {
22   ti_int s = (tu_int)a - (tu_int)b;
23   if (b >= 0) {
24     if (s > a)
25       compilerrt_abort();
26   } else {
27     if (s <= a)
28       compilerrt_abort();
29   }
30   return s;
31 }
32 
33 #endif // CRT_HAS_128BIT
34