w_atan2.c 1.4 KB

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  1. /* Copyright (C) 2011-2016 Free Software Foundation, Inc.
  2. This file is part of the GNU C Library.
  3. Contributed by Ulrich Drepper <drepper@gmail.com>, 2011.
  4. The GNU C Library is free software; you can redistribute it and/or
  5. modify it under the terms of the GNU Lesser General Public
  6. License as published by the Free Software Foundation; either
  7. version 2.1 of the License, or (at your option) any later version.
  8. The GNU C Library is distributed in the hope that it will be useful,
  9. but WITHOUT ANY WARRANTY; without even the implied warranty of
  10. MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  11. Lesser General Public License for more details.
  12. You should have received a copy of the GNU Lesser General Public
  13. License along with the GNU C Library; if not, see
  14. <http://www.gnu.org/licenses/>. */
  15. /*
  16. * wrapper atan2(y,x)
  17. */
  18. #include <math.h>
  19. #include "math_private.h"
  20. #if __UCLIBC_HAS_FENV__
  21. #include <errno.h>
  22. #endif
  23. double
  24. atan2 (double y, double x)
  25. {
  26. #if __UCLIBC_HAS_FENV__
  27. double z;
  28. if (__builtin_expect (x == 0.0 && y == 0.0, 0) && _LIB_VERSION == _SVID_)
  29. return __kernel_standard (y, x, 3); /* atan2(+-0,+-0) */
  30. z = __ieee754_atan2 (y, x);
  31. if (__builtin_expect (z == 0.0 && y != 0.0 && isfinite (x),0))
  32. __set_errno (ERANGE);
  33. return z;
  34. #else
  35. return __ieee754_atan2 (y, x);
  36. #endif
  37. }
  38. libm_hidden_def(atan2)