llvm-project/compiler-rt/lib/builtins/subvti3.c

40 lines
922 B
C

/* ===-- subvti3.c - Implement __subvti3 -----------------------------------===
*
* Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
* See https://llvm.org/LICENSE.txt for license information.
* SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
*
* ===----------------------------------------------------------------------===
*
* This file implements __subvti3 for the compiler_rt library.
*
* ===----------------------------------------------------------------------===
*/
#include "int_lib.h"
#ifdef CRT_HAS_128BIT
/* Returns: a - b */
/* Effects: aborts if a - b overflows */
COMPILER_RT_ABI ti_int
__subvti3(ti_int a, ti_int b)
{
ti_int s = (tu_int) a - (tu_int) b;
if (b >= 0)
{
if (s > a)
compilerrt_abort();
}
else
{
if (s <= a)
compilerrt_abort();
}
return s;
}
#endif /* CRT_HAS_128BIT */