w_llogb_template.c 1.4 KB

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  1. /* Wrapper to implement llogb in terms of ilogb.
  2. Copyright (C) 2012-2019 Free Software Foundation, Inc.
  3. This file is part of the GNU C Library.
  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. #include <math.h>
  16. #include <errno.h>
  17. #include <limits.h>
  18. #include <math_private.h>
  19. #include <fenv.h>
  20. long int
  21. M_DECL_FUNC (__llogb) (FLOAT x)
  22. {
  23. int r = M_SUF (__ieee754_ilogb) (x);
  24. long int lr = r;
  25. if (__glibc_unlikely (r == FP_ILOGB0)
  26. || __glibc_unlikely (r == FP_ILOGBNAN)
  27. || __glibc_unlikely (r == INT_MAX))
  28. {
  29. #if LONG_MAX != INT_MAX
  30. if (r == FP_ILOGB0)
  31. lr = FP_LLOGB0;
  32. else if (r == FP_ILOGBNAN)
  33. lr = FP_LLOGBNAN;
  34. else
  35. lr = LONG_MAX;
  36. #endif
  37. __set_errno (EDOM);
  38. __feraiseexcept (FE_INVALID);
  39. }
  40. return lr;
  41. }
  42. declare_mgen_alias (__llogb, llogb)