sp_simple.c 1.5 KB

1234567891011121314151617181920212223242526272829303132333435363738394041424344454647484950515253545556575859606162
  1. /* IEEE754 floating point arithmetic
  2. * single precision
  3. */
  4. /*
  5. * MIPS floating point support
  6. * Copyright (C) 1994-2000 Algorithmics Ltd.
  7. *
  8. * This program is free software; you can distribute it and/or modify it
  9. * under the terms of the GNU General Public License (Version 2) as
  10. * published by the Free Software Foundation.
  11. *
  12. * This program is distributed in the hope it will be useful, but WITHOUT
  13. * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  14. * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
  15. * for more details.
  16. *
  17. * You should have received a copy of the GNU General Public License along
  18. * with this program; if not, write to the Free Software Foundation, Inc.,
  19. * 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  20. */
  21. #include "ieee754sp.h"
  22. union ieee754sp ieee754sp_neg(union ieee754sp x)
  23. {
  24. union ieee754sp y;
  25. if (ieee754_csr.abs2008) {
  26. y = x;
  27. SPSIGN(y) = !SPSIGN(x);
  28. } else {
  29. unsigned int oldrm;
  30. oldrm = ieee754_csr.rm;
  31. ieee754_csr.rm = FPU_CSR_RD;
  32. y = ieee754sp_sub(ieee754sp_zero(0), x);
  33. ieee754_csr.rm = oldrm;
  34. }
  35. return y;
  36. }
  37. union ieee754sp ieee754sp_abs(union ieee754sp x)
  38. {
  39. union ieee754sp y;
  40. if (ieee754_csr.abs2008) {
  41. y = x;
  42. SPSIGN(y) = 0;
  43. } else {
  44. unsigned int oldrm;
  45. oldrm = ieee754_csr.rm;
  46. ieee754_csr.rm = FPU_CSR_RD;
  47. if (SPSIGN(x))
  48. y = ieee754sp_sub(ieee754sp_zero(0), x);
  49. else
  50. y = ieee754sp_add(ieee754sp_zero(0), x);
  51. ieee754_csr.rm = oldrm;
  52. }
  53. return y;
  54. }