using BenchmarkDotNet.Attributes;
using BenchmarkDotNet.Running;
using System.Runtime.CompilerServices;
using System.Runtime.InteropServices;
using System.Runtime.Intrinsics;

public class Benchmarks
{
    static void Main(string[] args)
    {
        BenchmarkSwitcher.FromAssembly(typeof(Benchmarks).Assembly).Run(args);
    }

    byte[] data = [0,0,0,11,0,0,0,12,0,0,0,13,0,0,0,14 ];

    [Benchmark]
    public int IndexOfAnyBench() => IndexOfAny(ref MemoryMarshal.GetReference(data), 13, 14);

    [Benchmark]
    public int LastIndexOfBench() => LastIndexOf(ref MemoryMarshal.GetReference(data), 13);

    [MethodImpl(MethodImplOptions.NoInlining)]
    static int IndexOfAny(ref byte haystack, byte needle1, byte needle2)
    {
        var data = Vector128.LoadUnsafe(ref haystack);
        var cmp1 = Vector128.Equals(data, Vector128.Create(needle1));
        var cmp2 = Vector128.Equals(data, Vector128.Create(needle2));
        return Vector128.IndexOfWhereAllBitsSet(cmp1 | cmp2);
    }

    [MethodImpl(MethodImplOptions.NoInlining)]
    static int LastIndexOf(ref byte haystack, byte needle1)
    {
        var data = Vector128.LoadUnsafe(ref haystack);
        var cmp1 = Vector128.Equals(data, Vector128.Create(needle1));
        return Vector128.IndexOfWhereAllBitsSet(cmp1);
    }
}

using BenchmarkDotNet.Attributes;
using BenchmarkDotNet.Running;
using System.Runtime.CompilerServices;
using System.Runtime.Intrinsics;

public class Benchmarks
{
    byte[] data1   = [0,0,0,11,0,0,0,12,0,0,0,13,0,0,0,14];
    ushort[] data2 = [0,0,0,11,0,0,0,12];
    byte[] data3 = new byte[1024];
    byte needle1 = 11;

    [Benchmark]
    public int IndexOfAnyBench() => IndexOfAny(data2, 13, 14);

    [Benchmark]
    public int IndexOfLoopBench()
    {
        Span<byte> span = data3;
        var val = Vector128.Create((byte)111);
        for (int i = 0; i < span.Length; i+= 16)
        {
            Vector128<byte> data = Vector128.Create(span);
            Vector128<byte> cmp = Vector128.Equals(data, val);
            int idx = Vector128.IndexOfWhereAllBitsSet(cmp);
            if (idx != -1)
            {
                return idx + i;
            }
        }

        return -1;
    }

    [Benchmark]
    public int LastIndexOfBench_Found() => LastIndexOf(data1, needle1);

    [Benchmark]
    public int LastIndexOfBench_NotFound() => LastIndexOf(data1, 42);

    [MethodImpl(MethodImplOptions.NoInlining)]
    static int IndexOfAny(Span<ushort> span, ushort needle1, ushort needle2)
    {
        var data = Vector128.Create(span);
        var cmp1 = Vector128.Equals(data, Vector128.Create(needle1));
        var cmp2 = Vector128.Equals(data, Vector128.Create(needle2));
        return Vector128.IndexOfWhereAllBitsSet(cmp1 | cmp2);
    }

    [MethodImpl(MethodImplOptions.NoInlining)]
    static int LastIndexOf(Span<byte> span, byte needle1)
    {
        var data = Vector128.Create(span);
        var cmp1 = Vector128.Equals(data, Vector128.Create(needle1));
        return Vector128.LastIndexOfWhereAllBitsSet(cmp1);
    }
}