diff options
Diffstat (limited to 'crypto/src/util/Integers.cs')
| -rw-r--r-- | crypto/src/util/Integers.cs | 20 |
1 files changed, 8 insertions, 12 deletions
diff --git a/crypto/src/util/Integers.cs b/crypto/src/util/Integers.cs index ab1868b74..eff7056b6 100644 --- a/crypto/src/util/Integers.cs +++ b/crypto/src/util/Integers.cs @@ -16,9 +16,11 @@ namespace Org.BouncyCastle.Utilities public const int NumBits = 32; public const int NumBytes = 4; +#if !NETCOREAPP3_0_OR_GREATER private static readonly byte[] DeBruijnTZ = { 0x1F, 0x00, 0x1B, 0x01, 0x1C, 0x0D, 0x17, 0x02, 0x1D, 0x15, 0x13, 0x0E, 0x18, 0x10, 0x03, 0x07, 0x1E, 0x1A, 0x0C, 0x16, 0x14, 0x12, 0x0F, 0x06, 0x19, 0x0B, 0x11, 0x05, 0x0A, 0x04, 0x09, 0x08 }; +#endif public static int HighestOneBit(int i) { @@ -50,12 +52,8 @@ namespace Org.BouncyCastle.Utilities public static int NumberOfLeadingZeros(int i) { #if NETCOREAPP3_0_OR_GREATER - if (Lzcnt.IsSupported) - { - return (int)Lzcnt.LeadingZeroCount((uint)i); - } -#endif - + return BitOperations.LeadingZeroCount((uint)i); +#else if (i <= 0) return (~i >> (31 - 5)) & (1 << 5); @@ -67,20 +65,18 @@ namespace Org.BouncyCastle.Utilities if (0 == (u >> 30)) { n += 2; u <<= 2; } n -= (int)(u >> 31); return n; +#endif } public static int NumberOfTrailingZeros(int i) { #if NETCOREAPP3_0_OR_GREATER - if (Bmi1.IsSupported) - { - return (int)Bmi1.TrailingZeroCount((uint)i); - } -#endif - + return BitOperations.TrailingZeroCount(i); +#else int n = DeBruijnTZ[(uint)((i & -i) * 0x0EF96A62) >> 27]; int m = (((i & 0xFFFF) | (int)((uint)i >> 16)) - 1) >> 31; return n - m; +#endif } public static int Reverse(int i) |