Integers.cs 2.6 KB

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  1. #if !BESTHTTP_DISABLE_ALTERNATE_SSL && (!UNITY_WEBGL || UNITY_EDITOR)
  2. #pragma warning disable
  3. using System;
  4. using BestHTTP.SecureProtocol.Org.BouncyCastle.Math.Raw;
  5. namespace BestHTTP.SecureProtocol.Org.BouncyCastle.Utilities
  6. {
  7. public abstract class Integers
  8. {
  9. public const int NumBits = 32;
  10. public const int NumBytes = 4;
  11. private static readonly byte[] DeBruijnTZ = {
  12. 0x1F, 0x00, 0x1B, 0x01, 0x1C, 0x0D, 0x17, 0x02, 0x1D, 0x15, 0x13, 0x0E, 0x18, 0x10, 0x03, 0x07,
  13. 0x1E, 0x1A, 0x0C, 0x16, 0x14, 0x12, 0x0F, 0x06, 0x19, 0x0B, 0x11, 0x05, 0x0A, 0x04, 0x09, 0x08 };
  14. public static int NumberOfLeadingZeros(int i)
  15. {
  16. if (i <= 0)
  17. return (~i >> (31 - 5)) & (1 << 5);
  18. uint u = (uint)i;
  19. int n = 1;
  20. if (0 == (u >> 16)) { n += 16; u <<= 16; }
  21. if (0 == (u >> 24)) { n += 8; u <<= 8; }
  22. if (0 == (u >> 28)) { n += 4; u <<= 4; }
  23. if (0 == (u >> 30)) { n += 2; u <<= 2; }
  24. n -= (int)(u >> 31);
  25. return n;
  26. }
  27. public static int NumberOfTrailingZeros(int i)
  28. {
  29. int n = DeBruijnTZ[(uint)((i & -i) * 0x0EF96A62) >> 27];
  30. int m = (((i & 0xFFFF) | (int)((uint)i >> 16)) - 1) >> 31;
  31. return n - m;
  32. }
  33. public static int Reverse(int i)
  34. {
  35. return (int)Reverse((uint)i);
  36. }
  37. public static uint Reverse(uint i)
  38. {
  39. i = Bits.BitPermuteStepSimple(i, 0x55555555U, 1);
  40. i = Bits.BitPermuteStepSimple(i, 0x33333333U, 2);
  41. i = Bits.BitPermuteStepSimple(i, 0x0F0F0F0FU, 4);
  42. return ReverseBytes(i);
  43. }
  44. public static int ReverseBytes(int i)
  45. {
  46. return (int)ReverseBytes((uint)i);
  47. }
  48. public static uint ReverseBytes(uint i)
  49. {
  50. return RotateLeft(i & 0xFF00FF00U, 8) |
  51. RotateLeft(i & 0x00FF00FFU, 24);
  52. }
  53. public static int RotateLeft(int i, int distance)
  54. {
  55. return (i << distance) ^ (int)((uint)i >> -distance);
  56. }
  57. public static uint RotateLeft(uint i, int distance)
  58. {
  59. return (i << distance) ^ (i >> -distance);
  60. }
  61. public static int RotateRight(int i, int distance)
  62. {
  63. return (int)((uint)i >> distance) ^ (i << -distance);
  64. }
  65. public static uint RotateRight(uint i, int distance)
  66. {
  67. return (i >> distance) ^ (i << -distance);
  68. }
  69. }
  70. }
  71. #pragma warning restore
  72. #endif