1//===-- subvdi3.c - Implement __subvdi3 -----------------------------------===//
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 __subvdi3 for the compiler_rt library.
10//
11//===----------------------------------------------------------------------===//
12
13#include "int_lib.h"
14
15// Returns: a - b
16
17// Effects: aborts if a - b overflows
18
19COMPILER_RT_ABI di_int __subvdi3(di_int a, di_int b) {
20 di_int s = (du_int)a - (du_int)b;
21 if (b >= 0) {
22 if (s > a)
23 compilerrt_abort();
24 } else {
25 if (s <= a)
26 compilerrt_abort();
27 }
28 return s;
29}
30

source code of compiler-rt/lib/builtins/subvdi3.c