israellot

public static unsafe uint ChecksumExpertAvx2(ReadOnlySpan<byte> arr)
{
        ref byte refSpan = ref MemoryMarshal.GetReference<byte>(arr);

        var z = 0;
        uint sum = 0;

        var vectorSum = Avx2.Xor(Vector256<byte>.Zero, Vector256<byte>.Zero).AsUInt32();
        var mask = Vector256.Create((byte)3, 2, 1, 0, 7, 6, 5, 4, 11, 10, 9, 8, 15, 14, 13, 12, (byte)3, 2, 1, 0, 7, 6, 5, 4, 11, 10, 9, 8, 15, 14, 13, 12);

israellot

public static unsafe uint ChecksumExpertAvx(ReadOnlySpan<byte> arr)
{
        ref byte refSpan = ref MemoryMarshal.GetReference<byte>(arr);

        uint z = 0;            
        uint sum = 0;
        
        var vectorSum = Avx.Xor(Vector128<byte>.Zero, Vector128<byte>.Zero).AsUInt32();  
        var mask = Vector128.Create((byte)3, 2, 1, 0, 7, 6, 5, 4, 11, 10, 9, 8, 15, 14, 13, 12);

israellot

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;

israellot

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

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

        var limit = arr.Length - 4;

israellot

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

    fixed (byte* ptr = arr)
    {
        uint sum0 = 0, sum1 = 0, sum2 = 0, sum3 = 0;
        uint z = 0;
        int rem = arr.Length % 32;

israellot

G_M000_IG06:                ;; offset=007BH
    mov      r15d, r11d
    mov      r12, qword ptr [rdx+r15]
    mov      r13, qword ptr [rdx+r15+08H]
    mov      rdi, qword ptr [rdx+r15+10H]
    mov      r15, qword ptr [rdx+r15+18H]
    mov      rcx, 0xFF00FF00FF00FF
    and      rcx, r12
    add      rsi, rcx
    mov      rcx, 0xFF00FF00FF00FF

israellot

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

    fixed (byte* ptr = arr)
    {
        uint sum0 = 0, sum1 = 0, sum2 = 0, sum3 = 0;
        uint z = 0;

        ulong tmp0 = 0, tmp1 = 0;

israellot

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

    fixed (byte* ptr = arr)
    {
        uint sum0 = 0, sum1 = 0, sum2 = 0, sum3 = 0;
        uint z = 0;
        int rem = arr.Length % 32;

israellot

//while (z < limit)
// {
//    sum0 += (uint)(ptr[z + 0] + ptr[z + 4] + ptr[z + 8] + ptr[z + 12]

//PRO
G_M000_IG06:                
    cmp      r11d, ecx
    jae      G_M000_IG17
    mov      ebx, r11d
    movzx    rbx, byte  ptr [rdx+rbx]

israellot

public static unsafe int PointerAccessInt(byte* ptr,int x,int y)
{
   return ptr[x]& ptr[x+y];
}

public static unsafe int PointerAccessUInt(byte* ptr,uint x,uint y)
{
   return ptr[x]& ptr[x+y];
}