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  1. /*++
  2.  
  3. Copyright (c) 1998  Intel Corporation
  4.  
  5. Module Name:
  6.  
  7.     math.c
  8.  
  9. Abstract:
  10.  
  11.  
  12.  
  13.  
  14. Revision History
  15.  
  16. --*/
  17.  
  18. #include "lib.h"
  19.  
  20.  
  21. //
  22. // Declare runtime functions
  23. //
  24.  
  25. #ifdef RUNTIME_CODE
  26. #pragma RUNTIME_CODE(LShiftU64)
  27. #pragma RUNTIME_CODE(RShiftU64)
  28. #pragma RUNTIME_CODE(MultU64x32)
  29. #pragma RUNTIME_CODE(DivU64x32)
  30. #endif
  31.  
  32. //
  33. //
  34. //
  35.  
  36.  
  37.  
  38.  
  39. UINT64
  40. LShiftU64 (
  41.     IN UINT64   Operand,
  42.     IN UINTN    Count
  43.     )
  44. // Left shift 64bit by 32bit and get a 64bit result
  45. {
  46.     return Operand << Count;
  47. }
  48.  
  49. UINT64
  50. RShiftU64 (
  51.     IN UINT64   Operand,
  52.     IN UINTN    Count
  53.     )
  54. // Right shift 64bit by 32bit and get a 64bit result
  55. {
  56.     return Operand >> Count;
  57. }
  58.  
  59.  
  60. UINT64
  61. MultU64x32 (
  62.     IN UINT64   Multiplicand,
  63.     IN UINTN    Multiplier
  64.     )
  65. // Multiple 64bit by 32bit and get a 64bit result
  66. {
  67.     return Multiplicand * Multiplier;
  68. }
  69.  
  70. UINT64
  71. DivU64x32 (
  72.     IN UINT64   Dividend,
  73.     IN UINTN    Divisor,
  74.     OUT UINTN   *Remainder OPTIONAL
  75.     )
  76. // divide 64bit by 32bit and get a 64bit result
  77. // N.B. only works for 31bit divisors!!
  78. {
  79.     ASSERT (Divisor != 0);
  80.  
  81.     if (Remainder) {
  82.         *Remainder = Dividend % Divisor;
  83.     }
  84.  
  85.     return Dividend / Divisor;
  86. }
  87.