lshrdi3.c 1.4 KB

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  1. /* lshrdi3.c extracted from gcc-2.7.2/libgcc2.c which is: */
  2. /* Copyright (C) 1989, 1992, 1993, 1994, 1995 Free Software Foundation, Inc.
  3. This file is part of GNU CC.
  4. GNU CC is free software; you can redistribute it and/or modify
  5. it under the terms of the GNU General Public License as published by
  6. the Free Software Foundation; either version 2, or (at your option)
  7. any later version.
  8. GNU CC is distributed in the hope that it will be useful,
  9. but WITHOUT ANY WARRANTY; without even the implied warranty of
  10. MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  11. GNU General Public License for more details. */
  12. #include <linux/compiler.h>
  13. #include <linux/export.h>
  14. #define BITS_PER_UNIT 8
  15. typedef int SItype __mode(SI);
  16. typedef unsigned int USItype __mode(SI);
  17. typedef int DItype __mode(DI);
  18. typedef int word_type __mode(__word__);
  19. struct DIstruct {SItype high, low;};
  20. typedef union
  21. {
  22. struct DIstruct s;
  23. DItype ll;
  24. } DIunion;
  25. DItype
  26. __lshrdi3 (DItype u, word_type b)
  27. {
  28. DIunion w;
  29. word_type bm;
  30. DIunion uu;
  31. if (b == 0)
  32. return u;
  33. uu.ll = u;
  34. bm = (sizeof (SItype) * BITS_PER_UNIT) - b;
  35. if (bm <= 0)
  36. {
  37. w.s.high = 0;
  38. w.s.low = (USItype)uu.s.high >> -bm;
  39. }
  40. else
  41. {
  42. USItype carries = (USItype)uu.s.high << bm;
  43. w.s.high = (USItype)uu.s.high >> b;
  44. w.s.low = ((USItype)uu.s.low >> b) | carries;
  45. }
  46. return w.ll;
  47. }
  48. EXPORT_SYMBOL(__lshrdi3);