Use intrinsic for GetHighestSetBitIndex (#7224)

NethermindEth · Jun 27, 2024 · 24f4142 · 24f4142
1 parent 229bd6b
commit 24f4142
Showing 1 changed file with 3 additions and 11 deletions.
diff --git a/src/Nethermind/Nethermind.Core/Extensions/Bytes.cs b/src/Nethermind/Nethermind.Core/Extensions/Bytes.cs
@@ -145,20 +145,12 @@ public static bool GetBit(this byte b, int bitNumber)
         [MethodImpl(MethodImplOptions.AggressiveInlining)]
         public static void SetBit(this ref byte b, int bitNumber)
         {
-            byte mask = (byte)(1 << (7 - bitNumber));
-            b = b |= mask;
+            int mask = (1 << (7 - bitNumber));
+            b |= (byte)mask;
         }
 
         public static int GetHighestSetBitIndex(this byte b)
-        {
-            if ((b & 128) == 128) return 8;
-            if ((b & 64) == 64) return 7;
-            if ((b & 32) == 32) return 6;
-            if ((b & 16) == 16) return 5;
-            if ((b & 8) == 8) return 4;
-            if ((b & 4) == 4) return 3;
-            return (b & 2) == 2 ? 2 : b;
-        }
+            => 32 - BitOperations.LeadingZeroCount((uint)b);
 
         [MethodImpl(MethodImplOptions.AggressiveInlining)]
         public static bool AreEqual(ReadOnlySpan<byte> a1, ReadOnlySpan<byte> a2)