absvsi2.c 825 B

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  1. //===-- absvsi2.c - Implement __absvsi2 -----------------------------------===//
  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 __absvsi2 for the compiler_rt library.
  10. //
  11. //===----------------------------------------------------------------------===//
  12. #include "int_lib.h"
  13. // Returns: absolute value
  14. // Effects: aborts if abs(x) < 0
  15. COMPILER_RT_ABI si_int __absvsi2(si_int a) {
  16. const int N = (int)(sizeof(si_int) * CHAR_BIT);
  17. if (a == ((si_int)((su_int)1 << (N - 1))))
  18. compilerrt_abort();
  19. const si_int t = a >> (N - 1);
  20. return (a ^ t) - t;
  21. }