Expert Checksum

crc32_expert.cs

public static unsafe uint ChecksumExpert(ReadOnlySpan<byte> arr)
{
    if (arr.Length == 0) return 0;

    fixed (byte* ptr = arr)
    {
        uint sum = 0;
        int z = 0;

        var limit = arr.Length - 32;
        while (z < limit)
        {
            sum += BinaryPrimitives.ReverseEndianness(*(uint*)(ptr + z));
            sum += BinaryPrimitives.ReverseEndianness(*(uint*)(ptr + z + 4));
            sum += BinaryPrimitives.ReverseEndianness(*(uint*)(ptr + z + 8));
            sum += BinaryPrimitives.ReverseEndianness(*(uint*)(ptr + z + 12));
            sum += BinaryPrimitives.ReverseEndianness(*(uint*)(ptr + z + 16));
            sum += BinaryPrimitives.ReverseEndianness(*(uint*)(ptr + z + 20));
            sum += BinaryPrimitives.ReverseEndianness(*(uint*)(ptr + z + 24));
            sum += BinaryPrimitives.ReverseEndianness(*(uint*)(ptr + z + 28));

            z += 32;
        }

        ...
    }
}