[WIP] UnalignedAccess Android tests

Author: matouskozak

src/tests/FunctionalTests/Android/Device_Emulator/UnalignedAccess/Android.Device_Emulator.UnalignedAccess.Test.csproj

@@ -0,0 +1,14 @@
+<Project Sdk="Microsoft.NET.Sdk">
+  <PropertyGroup>
+    <OutputType>Exe</OutputType>
+    <RunAOTCompilation>false</RunAOTCompilation>
+    <TestRuntime>true</TestRuntime>
+    <TargetFramework>$(NetCoreAppCurrent)</TargetFramework>
+    <MainLibraryFileName>Android.Device_Emulator.UnalignedAccess.Test.dll</MainLibraryFileName>
+    <ExpectedExitCode>42</ExpectedExitCode>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <Compile Include="Program.cs" />
+  </ItemGroup>
+</Project>

src/tests/FunctionalTests/Android/Device_Emulator/UnalignedAccess/Program.cs

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+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+
+using System;
+using System.Runtime.InteropServices;
+using System.Buffers.Binary;
+
+public class Program
+{
+    [StructLayout(LayoutKind.Sequential, Size=12)]
+    struct S {
+        public double d1;
+        public int i2;
+    }
+
+    [StructLayout(LayoutKind.Sequential)]
+    struct H {
+        public S s1;
+        public int i3;
+        public byte b4;
+    }
+
+    public static int Main()
+    {
+        Console.WriteLine("Hello, Android!"); 
+
+        Console.WriteLine(Marshal.SizeOf(typeof(S)));
+        var a2 = new S[2];
+        a2[1].d1 = 2.12;
+        Console.WriteLine (a2[1].d1);
+        var h1 = new H();
+        h1.s1.d1 = 4.0;
+        h1.i3 = 15;
+        h1.b4 = 42;
+        unsafe {
+            fixed (S* parr = &a2[0])
+            {
+                byte* ptr = (byte*)parr;
+                ptr += 12;
+                Console.WriteLine ($"0x{((IntPtr)ptr):x}");
+                Console.WriteLine (*(ptr + 0));
+                Console.WriteLine (*(ptr + 1));
+                Console.WriteLine (*(ptr + 2));
+                Console.WriteLine (*(ptr + 3));
+                Console.WriteLine (*(ptr + 4));
+                Console.WriteLine (*(ptr + 5));
+                Console.WriteLine (*(ptr + 6));
+                Console.WriteLine (*(ptr + 7));
+                Span<byte> tmp = stackalloc byte[8];
+                new Span<byte>(ptr, 8).CopyTo(tmp);
+                double d = BinaryPrimitives.ReadDoubleLittleEndian(tmp);
+                Console.WriteLine ($"tmp = {d}");
+                if (d != 2.12) // if this prints 2.12 - unaligned load happened
+                    return 1;
+            }  
+            {
+                byte* ptr = (byte*)&h1;
+                Console.WriteLine (*(ptr + 12));
+                Console.WriteLine (*(ptr + 13));
+                Console.WriteLine (*(ptr + 14));
+                Console.WriteLine (*(ptr + 15));
+                Console.WriteLine (*(ptr + 16));
+            }
+        }
+
+        return 42;
+    }
+}