dp_simple.c 1.9 KB

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  1. /* IEEE754 floating point arithmetic
  2. * double precision: common utilities
  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 "ieee754dp.h"
  27. int ieee754dp_finite(ieee754dp x)
  28. {
  29. return DPBEXP(x) != DP_EMAX + 1 + DP_EBIAS;
  30. }
  31. ieee754dp ieee754dp_copysign(ieee754dp x, ieee754dp y)
  32. {
  33. CLEARCX;
  34. DPSIGN(x) = DPSIGN(y);
  35. return x;
  36. }
  37. ieee754dp ieee754dp_neg(ieee754dp x)
  38. {
  39. COMPXDP;
  40. EXPLODEXDP;
  41. CLEARCX;
  42. FLUSHXDP;
  43. if (xc == IEEE754_CLASS_SNAN) {
  44. SETCX(IEEE754_INVALID_OPERATION);
  45. return ieee754dp_nanxcpt(ieee754dp_indef(), "neg");
  46. }
  47. if (ieee754dp_isnan(x)) /* but not infinity */
  48. return ieee754dp_nanxcpt(x, "neg", x);
  49. /* quick fix up */
  50. DPSIGN(x) ^= 1;
  51. return x;
  52. }
  53. ieee754dp ieee754dp_abs(ieee754dp x)
  54. {
  55. COMPXDP;
  56. EXPLODEXDP;
  57. CLEARCX;
  58. FLUSHXDP;
  59. if (xc == IEEE754_CLASS_SNAN) {
  60. SETCX(IEEE754_INVALID_OPERATION);
  61. return ieee754dp_nanxcpt(ieee754dp_indef(), "neg");
  62. }
  63. if (ieee754dp_isnan(x)) /* but not infinity */
  64. return ieee754dp_nanxcpt(x, "abs", x);
  65. /* quick fix up */
  66. DPSIGN(x) = 0;
  67. return x;
  68. }