lshrdi3.c 2.3 KB

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  1. /*-
  2. * Copyright (c) 1992, 1993
  3. * The Regents of the University of California. All rights reserved.
  4. *
  5. * This software was developed by the Computer Systems Engineering group
  6. * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and
  7. * contributed to Berkeley.
  8. *
  9. * Redistribution and use in source and binary forms, with or without
  10. * modification, are permitted provided that the following conditions
  11. * are met:
  12. * 1. Redistributions of source code must retain the above copyright
  13. * notice, this list of conditions and the following disclaimer.
  14. * 2. Redistributions in binary form must reproduce the above copyright
  15. * notice, this list of conditions and the following disclaimer in the
  16. * documentation and/or other materials provided with the distribution.
  17. * 3. Neither the name of the University nor the names of its contributors
  18. * may be used to endorse or promote products derived from this software
  19. * without specific prior written permission.
  20. *
  21. * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  22. * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  23. * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  24. * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  25. * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  26. * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  27. * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  28. * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  29. * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  30. * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  31. * SUCH DAMAGE.
  32. *
  33. * From:
  34. * @(#)lshrdi3.c 8.1 (Berkeley) 6/4/93
  35. * $NetBSD: lshrdi3.c,v 1.1 2005/12/20 19:28:51 christos Exp
  36. */
  37. #include "longlong.h"
  38. /*
  39. * Shift an (unsigned) long long value right (logical shift right).
  40. */
  41. long long
  42. __lshrdi3(long long a, unsigned int shift)
  43. {
  44. union uu aa;
  45. if (shift == 0)
  46. return(a);
  47. aa.ll = a;
  48. if (shift >= INT_BITS) {
  49. aa.ui[L] = aa.ui[H] >> (shift - INT_BITS);
  50. aa.ui[H] = 0;
  51. } else {
  52. aa.ui[L] = (aa.ui[L] >> shift) |
  53. (aa.ui[H] << (INT_BITS - shift));
  54. aa.ui[H] >>= shift;
  55. }
  56. return (aa.ll);
  57. }