sp_simple.c 1.8 KB

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  1. /* IEEE754 floating point arithmetic
  2. * single precision
  3. */
  4. /*
  5. * MIPS floating point support
  6. * Copyright (C) 1994-2000 Algorithmics Ltd.
  7. * http://www.algor.co.uk
  8. *
  9. * ########################################################################
  10. *
  11. * This program is free software; you can distribute it and/or modify it
  12. * under the terms of the GNU General Public License (Version 2) as
  13. * published by the Free Software Foundation.
  14. *
  15. * This program is distributed in the hope it will be useful, but WITHOUT
  16. * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  17. * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
  18. * for more details.
  19. *
  20. * You should have received a copy of the GNU General Public License along
  21. * with this program; if not, write to the Free Software Foundation, Inc.,
  22. * 59 Temple Place - Suite 330, Boston MA 02111-1307, USA.
  23. *
  24. * ########################################################################
  25. */
  26. #include "ieee754sp.h"
  27. int ieee754sp_finite(ieee754sp x)
  28. {
  29. return SPBEXP(x) != SP_EMAX + 1 + SP_EBIAS;
  30. }
  31. ieee754sp ieee754sp_copysign(ieee754sp x, ieee754sp y)
  32. {
  33. CLEARCX;
  34. SPSIGN(x) = SPSIGN(y);
  35. return x;
  36. }
  37. ieee754sp ieee754sp_neg(ieee754sp x)
  38. {
  39. COMPXSP;
  40. EXPLODEXSP;
  41. CLEARCX;
  42. FLUSHXSP;
  43. /*
  44. * Invert the sign ALWAYS to prevent an endless recursion on
  45. * pow() in libc.
  46. */
  47. /* quick fix up */
  48. SPSIGN(x) ^= 1;
  49. if (xc == IEEE754_CLASS_SNAN) {
  50. ieee754sp y = ieee754sp_indef();
  51. SETCX(IEEE754_INVALID_OPERATION);
  52. SPSIGN(y) = SPSIGN(x);
  53. return ieee754sp_nanxcpt(y, "neg");
  54. }
  55. return x;
  56. }
  57. ieee754sp ieee754sp_abs(ieee754sp x)
  58. {
  59. COMPXSP;
  60. EXPLODEXSP;
  61. CLEARCX;
  62. FLUSHXSP;
  63. /* Clear sign ALWAYS, irrespective of NaN */
  64. SPSIGN(x) = 0;
  65. if (xc == IEEE754_CLASS_SNAN) {
  66. return ieee754sp_nanxcpt(ieee754sp_indef(), "abs");
  67. }
  68. return x;
  69. }