qp_qtod.c 1.4 KB

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  1. /* Software floating-point emulation.
  2. Return (double)(*a)
  3. Copyright (C) 1997-2017 Free Software Foundation, Inc.
  4. This file is part of the GNU C Library.
  5. Contributed by Richard Henderson (rth@cygnus.com) and
  6. Jakub Jelinek (jj@ultra.linux.cz).
  7. The GNU C Library is free software; you can redistribute it and/or
  8. modify it under the terms of the GNU Lesser General Public
  9. License as published by the Free Software Foundation; either
  10. version 2.1 of the License, or (at your option) any later version.
  11. The GNU C Library is distributed in the hope that it will be useful,
  12. but WITHOUT ANY WARRANTY; without even the implied warranty of
  13. MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  14. Lesser General Public License for more details.
  15. You should have received a copy of the GNU Lesser General Public
  16. License along with the GNU C Library; if not, see
  17. <http://www.gnu.org/licenses/>. */
  18. #include "soft-fp.h"
  19. #include "double.h"
  20. #include "quad.h"
  21. double _Qp_qtod(const long double *a)
  22. {
  23. FP_DECL_EX;
  24. FP_DECL_Q(A);
  25. FP_DECL_D(R);
  26. double r;
  27. FP_INIT_ROUNDMODE;
  28. FP_UNPACK_SEMIRAW_QP(A, a);
  29. #if (2 * _FP_W_TYPE_SIZE) < _FP_FRACBITS_Q
  30. FP_TRUNC(D,Q,2,4,R,A);
  31. #else
  32. FP_TRUNC(D,Q,1,2,R,A);
  33. #endif
  34. FP_PACK_SEMIRAW_D(r, R);
  35. QP_HANDLE_EXCEPTIONS(__asm (
  36. " ldd [%1], %%f52\n"
  37. " ldd [%1+8], %%f54\n"
  38. " fqtod %%f52, %0\n"
  39. " " : "=&e" (r) : "r" (a) : QP_CLOBBER));
  40. return r;
  41. }