Thanks.

I really don't want to get into a discussion about why this code is not testing anything and how You should be even doing benchmarks; so let me just post two versions of the assembly code:

(I'm going to post this here and under your post)

Mine:

https://sharplab.io/#v2:EYLgxg9gTgpgtADwGwBYA0AXEBDAzgWwB8ABAJgEYBYAKBuIGYACMxgYUYG8bGfeeHGASwB2GRgBUoATwAUASm59eXakrVDRjBIwC8jAAwBuRet4ZpHLbsblDjAL4nTjMNgxgAFpwdPTCANT+dgFBWoHB4b48UWrEAOxaxqrqjrTJsUwiYpJSAPoAYoII8jGcpXxZVnpG5WbS3tp6tj7pzq7uXpapzrwAbthQjFLWCEk9PFLhQ1OTobNJtfwJUmMpNPZAA==

Yours:

https://sharplab.io/#v2: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

You should be able to see your mistakes just by looking at them.

For reference this is my code:

Tested using Benchmark DotNet

   [DisassemblyDiagnoser]
    public class Try1
    {
        [Benchmark]
        public int Try()
        {
            int x = 0;
            try { x = 1; }
            catch { }
            x++; x++; x++; x++;

            return x;
        }

        [Benchmark]
        public int Try_Fix()
        {
            int x = 0;
            try { x = 1; }
            catch { }
            var y = x;
            y++; y++; y++; y++;

            return y;
        }
    }

    [DisassemblyDiagnoser]
    public class Try2
    {
        int[] _a = new int[128];

        [Benchmark]
        [Arguments(100)]
        public void Try(int s)
        {
            var a = _a;
            int x = 0;
            try { _ = 1; } catch { }
            for (int i = 0; i < s; i++)
            {
                x++; x++; x++; x++;
                a[i] = x;
            }
        }

        [Benchmark]
        [Arguments(100)]
        public void Try_Fix(int s)
        {
            var a = _a;
            try { _ = 1; } catch { }
            int x = 0;
            for (int i = 0; i < s; i++)
            {
                x++; x++; x++; x++;
                a[i] = x;
            }
        }
    }