compiler-rt/lib/builtins/negvsi2.c

   1 //===-- negvsi2.c - Implement __negvsi2 -----------------------------------===//
   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 __negvsi2 for the compiler_rt library.
  10 //
  11 //===----------------------------------------------------------------------===//
  12
  13 #include "int_lib.h"
  14
  15 // Returns: -a
  16
  17 // Effects: aborts if -a overflows
  18
  19 COMPILER_RT_ABI si_int __negvsi2(si_int a) {
  20   const si_int MIN =
  21       (si_int)((su_int)1 << ((int)(sizeof(si_int) * CHAR_BIT) - 1));
  22   if (a == MIN)
  23     compilerrt_abort();
  24   return -a;
  25 }