Added HasZeroByte APIs

Author: Sergio0694

Microsoft.Toolkit.HighPerformance/Helpers/BitHelper.cs

@@ -103,6 +103,37 @@ public static bool HasLookupFlag(uint table, int x, int min = 0)
             return valid;
         }
 
+        /// <summary>
+        /// Checks whether the given value has any bytes that are set to 0.
+        /// That is, given a <see cref="uint"/> value, which has a total of 4 bytes,
+        /// it checks whether any of those have all the bits set to 0.
+        /// </summary>
+        /// <param name="value">The input value to check.</param>
+        /// <returns>Whether <paramref name="value"/> has any bytes set to 0.</returns>
+        /// <remarks>
+        /// This method contains no branches.
+        /// For more info, see <see href="https://graphics.stanford.edu/~seander/bithacks.html"/>.
+        /// </remarks>
+        [Pure]
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        public static bool HasZeroByte(uint value)
+        {
+            return ((value - 0x0101_0101u) & ~value & 0x8080_8080u) != 0;
+        }
+
+        /// <summary>
+        /// Checks whether the given value has any bytes that are set to 0.
+        /// This method mirrors <see cref="HasZeroByte(uint)"/>, but with <see cref="ulong"/> values.
+        /// </summary>
+        /// <param name="value">The input value to check.</param>
+        /// <returns>Whether <paramref name="value"/> has any bytes set to 0.</returns>
+        [Pure]
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        public static bool HasZeroByte(ulong value)
+        {
+            return ((value - 0x0101_0101_0101_0101ul) & ~value & 0x8080_8080_8080_8080ul) != 0;
+        }
+
         /// <summary>
         /// Sets a bit to a specified value.
         /// </summary>