C# Unsafe and semi-safe sum

Program.cs

using System.Collections.Generic;
using System.Linq;
using System.Runtime.CompilerServices;
using System.Runtime.InteropServices;
using BenchmarkDotNet.Attributes;
using BenchmarkDotNet.Running;

namespace SumTest
{
    class Program
    {
        static void Main(string[] args)
        {
            BenchmarkRunner.Run<TestSafeAndUnsafeSum>();
        }
    }

    [DisassemblyDiagnoser]
    public class TestSafeAndUnsafeSum
    {
        public IEnumerable<object[]> Data()
        {
            yield return new object[] { Enumerable.Range(0,    100_000).ToArray(),    100_000 };
            yield return new object[] { Enumerable.Range(0,  1_000_000).ToArray(),  1_000_000 };
            yield return new object[] { Enumerable.Range(0, 10_000_000).ToArray(), 10_000_000 };
        }

        [Benchmark]
        [MethodImpl(MethodImplOptions.NoInlining)]
        [ArgumentsSource(nameof(Data))]
        public int SumDirect(int[] ints, int length)
        {
            int sum = 0;
            for (int i = 0; i < ints.Length; i++)
            {
                sum += ints[i];
            }
            return sum;
        }

        [MethodImpl(MethodImplOptions.AggressiveInlining)]
        static T FastAccessValue<T>(T[] ar, int index)
        {
            ref T tableRef = ref MemoryMarshal.GetArrayDataReference(ar);
            return Unsafe.Add(ref tableRef, (nint)index);
        }

        [Benchmark]
        [MethodImpl(MethodImplOptions.NoInlining)]
        [ArgumentsSource(nameof(Data))]
        public int SumUnsafe(int[] ints, int length)
        {
            int sum = 0;
            for (int i = 0; i < length; i++)
            {
                sum += FastAccessValue(ints, i);
            }
            return sum;
        }
    }
}

SumTest.csproj

<Project Sdk="Microsoft.NET.Sdk">

  <PropertyGroup>
    <OutputType>Exe</OutputType>
    <TargetFramework>net5.0</TargetFramework>
    <AllowUnsafeBlocks>true</AllowUnsafeBlocks>
  </PropertyGroup>

  <ItemGroup>
    <PackageReference Include="BenchmarkDotNet" Version="0.12.1" />
  </ItemGroup>

</Project>

Run result

BenchmarkDotNet=v0.12.1, OS=Windows 10.0.19042
Intel Core i7-9750H CPU 2.60GHz, 1 CPU, 12 logical and 6 physical cores
.NET Core SDK=5.0.201
  [Host]     : .NET Core 5.0.4 (CoreCLR 5.0.421.11614, CoreFX 5.0.421.11614), X64 RyuJIT
  DefaultJob : .NET Core 5.0.4 (CoreCLR 5.0.421.11614, CoreFX 5.0.421.11614), X64 RyuJIT

Method	ints	length	Mean	Error	StdDev	Code Size
SumDirect	Int32[100000]	100000	80.13 μs	0.748 μs	0.700 μs	29 B
SumUnsafe	Int32[100000]	100000	81.99 μs	0.535 μs	0.446 μs	33 B
SumDirect	Int32[1000000]	1000000	854.73 μs	5.216 μs	4.624 μs	29 B
SumUnsafe	Int32[1000000]	1000000	795.10 μs	2.680 μs	2.238 μs	33 B
SumDirect	Int32[10000000]	10000000	10,104.72 μs	27.199 μs	22.712 μs	29 B
SumUnsafe	Int32[10000000]	10000000	9,126.06 μs	30.329 μs	26.886 μs	33 B