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| author | Peter Dettman <peter.dettman@bouncycastle.org> | 2022-11-20 01:52:09 +0700 |
|---|---|---|
| committer | Peter Dettman <peter.dettman@bouncycastle.org> | 2022-11-20 01:52:09 +0700 |
| commit | 5e360a4f058a6497a5c750fa98b9cd15cd2000a0 (patch) | |
| tree | 20e44a5287cebe81059f0c24a3a37c4ecd5f6bc3 /crypto/src/util/Longs.cs | |
| parent | Refactoring (diff) | |
| download | BouncyCastle.NET-ed25519-5e360a4f058a6497a5c750fa98b9cd15cd2000a0.tar.xz | |
Use BitOperations for clz, ctz
Diffstat (limited to '')
| -rw-r--r-- | crypto/src/util/Longs.cs | 20 |
1 files changed, 8 insertions, 12 deletions
diff --git a/crypto/src/util/Longs.cs b/crypto/src/util/Longs.cs index 02ffb7676..18be945e9 100644 --- a/crypto/src/util/Longs.cs +++ b/crypto/src/util/Longs.cs @@ -16,11 +16,13 @@ namespace Org.BouncyCastle.Utilities public const int NumBits = 64; public const int NumBytes = 8; +#if !NETCOREAPP3_0_OR_GREATER private static readonly byte[] DeBruijnTZ = { 0x3F, 0x00, 0x01, 0x34, 0x02, 0x06, 0x35, 0x1A, 0x03, 0x25, 0x28, 0x07, 0x21, 0x36, 0x2F, 0x1B, 0x3D, 0x04, 0x26, 0x2D, 0x2B, 0x29, 0x15, 0x08, 0x17, 0x22, 0x3A, 0x37, 0x30, 0x11, 0x1C, 0x0A, 0x3E, 0x33, 0x05, 0x19, 0x24, 0x27, 0x20, 0x2E, 0x3C, 0x2C, 0x2A, 0x14, 0x16, 0x39, 0x10, 0x09, 0x32, 0x18, 0x23, 0x1F, 0x3B, 0x13, 0x38, 0x0F, 0x31, 0x1E, 0x12, 0x0E, 0x1D, 0x0D, 0x0C, 0x0B }; +#endif public static long HighestOneBit(long i) { @@ -53,12 +55,8 @@ namespace Org.BouncyCastle.Utilities public static int NumberOfLeadingZeros(long i) { #if NETCOREAPP3_0_OR_GREATER - if (Lzcnt.X64.IsSupported) - { - return (int)Lzcnt.X64.LeadingZeroCount((ulong)i); - } -#endif - + return BitOperations.LeadingZeroCount((ulong)i); +#else int x = (int)(i >> 32), n = 0; if (x == 0) { @@ -66,20 +64,18 @@ namespace Org.BouncyCastle.Utilities x = (int)i; } return n + Integers.NumberOfLeadingZeros(x); +#endif } public static int NumberOfTrailingZeros(long i) { #if NETCOREAPP3_0_OR_GREATER - if (Bmi1.X64.IsSupported) - { - return (int)Bmi1.X64.TrailingZeroCount((ulong)i); - } -#endif - + return BitOperations.TrailingZeroCount((ulong)i); +#else int n = DeBruijnTZ[(uint)((ulong)((i & -i) * 0x045FBAC7992A70DAL) >> 58)]; long m = (((i & 0xFFFFFFFFL) | (long)((ulong)i >> 32)) - 1L) >> 63; return n - (int)m; +#endif } public static long Reverse(long i) |