JIT: (bug) constant-NaN Math.Min/Max folding drops the other argument's side effects #133718

using System;
using System.Runtime.CompilerServices;

class P
{
    static double[] a = new double[1];

    [MethodImpl(MethodImplOptions.NoInlining | MethodImplOptions.AggressiveOptimization)]
    static double Test(int i)
    {
        return Math.Min(a[i], double.NaN);
    }

    static void Main()
    {
        try
        {
            Console.WriteLine("NO EXCEPTION, result=" + Test(5));
        }
        catch (IndexOutOfRangeException)
        {
            Console.WriteLine("IndexOutOfRangeException (correct)");
        }
    }
}

Expected: IndexOutOfRangeException (correct) — a[5] on a length-1 array must throw before Math.Min returns.
Actual: NO EXCEPTION, result=NaN — the array load, including its bounds check, is discarded.

Notes:

• run.ps1 -Cs repro.cs (csc -optimize+, Checked corerun x64). Compiling with -optimize- prints the correct IndexOutOfRangeException, so it is purely the optimized-JIT path.
• src\coreclr\jit\gentree.cpp in gtNewSimdMinMaxNode: the isNaN shortcut does return cnsNode; (non-Number) / return otherNode; (Number) with no gtExtractSideEffList/COMMA for the discarded operand.
• Only on the non-AVX10v2 xarch path (the AVX10v2 branch is taken earlier and is unaffected). Same shape works for MathF.Min, Math.Max, and the MinNumber/MaxNumber variants (drop the other operand there).