change for make it fast

[rootflood]

hi, i test your benchmark and get unexcepted results:
my first test was on this class :
https://github.com/aalmada/ArrayIteration/blob/master/Benchmarks/ReadSliceBenchmarks.cs

result :

Method	Count	Mean	Error	StdDev	Ratio	RatioSD	Gen 0	Gen 1	Gen 2	Allocated
Array_ForEach	1000000	734.8 us	2.40 us	2.25 us	baseline		-	-	-	-
Array_For	1000000	1,057.0 us	4.98 us	4.66 us	1.44x slower	0.01x	-	-	-	-
Span_ForEach	1000000	1,056.6 us	4.37 us	4.09 us	1.44x slower	0.01x	-	-	-	-
ArraySegment_For	1000000	1,416.9 us	15.32 us	14.33 us	1.93x slower	0.02x	-	-	-	-
ArraySegment_ForEach	1000000	4,734.6 us	14.97 us	14.00 us	6.44x slower	0.03x	-	-	-	-
ArraySegment_Linq	1000000	9,884.1 us	82.45 us	73.09 us	13.45x slower	0.11x	-	-	-	72 B
ArraySegment_ArrayFor	1000000	1,091.8 us	20.93 us	25.70 us	1.49x slower	0.04x	-	-	-	-
ArraySegment_SpanForEach	1000000	1,117.2 us	22.15 us	35.77 us	1.53x slower	0.05x	-	-	-	-

and when i remove some of methods get me other result.
code:

 public class ReadSliceBenchmarks : ReadBenchmarksBase
    {

        [Benchmark(Baseline = true)]
        public int Array_ForEach()
            => Sum.ForEach(_array);

        [Benchmark]
        public int Array_For()
            => Sum.For(_array, 0, _array.Length);

        [Benchmark]
        public int Span_ForEach()
            => Sum.ForEach(_array.AsSpan());

        [Benchmark]
        public int ArraySegment_For()
            => Sum.For(_arraySegment);

        //[Benchmark]
        //public int ArraySegment_ForEach()
        //    => Sum.ForEach(_arraySegment);

        //[Benchmark]
        //public int ArraySegment_Linq()
        //    => _arraySegment.Sum();

        //[Benchmark]
        //public int ArraySegment_ArrayFor()
        //    => Sum.For(_arraySegment.Array, _arraySegment.Offset, _arraySegment.Count);

        //[Benchmark]
        //public int ArraySegment_SpanForEach()
        //    => Sum.ForEach(_arraySegment.AsSpan());

    }

Result:

Method	Count	Mean	Error	StdDev	Ratio	RatioSD	Gen 0	Gen 1	Gen 2	Allocated
Array_ForEach	1000000	1.098 ms	0.0212 ms	0.0217 ms	baseline		-	-	-	-
Array_For	1000000	1.086 ms	0.0214 ms	0.0246 ms	1.01x faster	0.03x	-	-	-	-
Span_ForEach	1000000	1.077 ms	0.0169 ms	0.0149 ms	1.02x faster	0.03x	-	-	-	-
ArraySegment_For	1000000	1.435 ms	0.0285 ms	0.0305 ms	1.31x slower	0.04x	-	-	-	-

this is related to dotnet/runtime#54758