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
21COMPILER_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

source code of compiler-rt/lib/builtins/subvti3.c