dp_simple.c 1.8 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. *
  8. * ########################################################################
  9. *
  10. * This program is free software; you can distribute it and/or modify it
  11. * under the terms of the GNU General Public License (Version 2) as
  12. * published by the Free Software Foundation.
  13. *
  14. * This program is distributed in the hope it will be useful, but WITHOUT
  15. * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  16. * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
  17. * for more details.
  18. *
  19. * You should have received a copy of the GNU General Public License along
  20. * with this program; if not, write to the Free Software Foundation, Inc.,
  21. * 59 Temple Place - Suite 330, Boston MA 02111-1307, USA.
  22. *
  23. * ########################################################################
  24. */
  25. #include "ieee754dp.h"
  26. int ieee754dp_finite(ieee754dp x)
  27. {
  28. return DPBEXP(x) != DP_EMAX + 1 + DP_EBIAS;
  29. }
  30. ieee754dp ieee754dp_copysign(ieee754dp x, ieee754dp y)
  31. {
  32. CLEARCX;
  33. DPSIGN(x) = DPSIGN(y);
  34. return x;
  35. }
  36. ieee754dp ieee754dp_neg(ieee754dp x)
  37. {
  38. COMPXDP;
  39. EXPLODEXDP;
  40. CLEARCX;
  41. FLUSHXDP;
  42. /*
  43. * Invert the sign ALWAYS to prevent an endless recursion on
  44. * pow() in libc.
  45. */
  46. /* quick fix up */
  47. DPSIGN(x) ^= 1;
  48. if (xc == IEEE754_CLASS_SNAN) {
  49. ieee754dp y = ieee754dp_indef();
  50. SETCX(IEEE754_INVALID_OPERATION);
  51. DPSIGN(y) = DPSIGN(x);
  52. return ieee754dp_nanxcpt(y, "neg");
  53. }
  54. return x;
  55. }
  56. ieee754dp ieee754dp_abs(ieee754dp x)
  57. {
  58. COMPXDP;
  59. EXPLODEXDP;
  60. CLEARCX;
  61. FLUSHXDP;
  62. /* Clear sign ALWAYS, irrespective of NaN */
  63. DPSIGN(x) = 0;
  64. if (xc == IEEE754_CLASS_SNAN) {
  65. SETCX(IEEE754_INVALID_OPERATION);
  66. return ieee754dp_nanxcpt(ieee754dp_indef(), "abs");
  67. }
  68. return x;
  69. }