Make it possible to build/run tests on linux-arm64

I wanted to run the roslyn test suite on Linux on arm64. Building
everything worked, but running tests would fail with errors like:

    Errors Microsoft.CodeAnalysis.CSharp.Emit.UnitTests_1
    Could not find 'dotnet' host for the 'X64' architecture.

    You can resolve the problem by installing the 'X64' .NET.

With the changes in this commit, I can build and run all tests using:

    $ ./eng/build.sh --restore --build --pack
    $ ./eng/build.sh --test

I would, eventually, like to be able to run the tests on other
platforms, including s390x and ppc64le. Hopefully that might help
identify/fix issues like dotnet#74392
earlier.

One thing I am not too happy about in this change is how many places
need an explicit addition of "linux-arm64". That won't scale as we want
to add more architectures.

eng/Directory.Packages.props

@@ -290,9 +290,11 @@
     <PackageVersion Include="xunit.extensibility.execution" Version="$(xunitVersion)" />
     <PackageVersion Include="XunitXml.TestLogger" Version="2.1.26" />
     <PackageVersion Include="runtime.win-x64.Microsoft.NETCore.ILDAsm" Version="$(ILDAsmPackageVersion)" />
+    <PackageVersion Include="runtime.linux-arm64.Microsoft.NETCore.ILDAsm" Version="$(ILDAsmPackageVersion)" />
     <PackageVersion Include="runtime.linux-x64.Microsoft.NETCore.ILDAsm" Version="$(ILDAsmPackageVersion)" />
     <PackageVersion Include="runtime.osx-x64.Microsoft.NETCore.ILDAsm" Version="$(ILDAsmPackageVersion)" />
     <PackageVersion Include="runtime.win-x64.Microsoft.NETCore.ILAsm" Version="$(ILAsmPackageVersion)" />
+    <PackageVersion Include="runtime.linux-arm64.Microsoft.NETCore.ILAsm" Version="$(ILAsmPackageVersion)" />
     <PackageVersion Include="runtime.linux-x64.Microsoft.NETCore.ILAsm" Version="$(ILAsmPackageVersion)" />
     <PackageVersion Include="runtime.osx-x64.Microsoft.NETCore.ILAsm" Version="$(ILAsmPackageVersion)" />
     <PackageVersion Include="Basic.CompilerLog.Util" Version="0.6.1" />

eng/targets/ILAsm.targets

@@ -12,6 +12,12 @@
       <Visible>false</Visible>
       <Pack>false</Pack>
     </Content>
+    <Content Include="$(Pkgruntime_linux-arm64_Microsoft_NETCore_ILAsm)\runtimes\**\*.*">
+      <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
+      <LinkBase>runtimes</LinkBase>
+      <Visible>false</Visible>
+      <Pack>false</Pack>
+    </Content>
     <Content Include="$(Pkgruntime_linux-x64_Microsoft_NETCore_ILAsm)\runtimes\**\*.*">
       <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
       <LinkBase>runtimes</LinkBase>
@@ -26,7 +32,8 @@
     </Content>
 
     <PackageReference Include="runtime.win-x64.Microsoft.NETCore.ILAsm" GeneratePathProperty="true" ExcludeAssets="all" />
+    <PackageReference Include="runtime.linux-arm64.Microsoft.NETCore.ILAsm" GeneratePathProperty="true" ExcludeAssets="all" />
     <PackageReference Include="runtime.linux-x64.Microsoft.NETCore.ILAsm" GeneratePathProperty="true" ExcludeAssets="all" />
     <PackageReference Include="runtime.osx-x64.Microsoft.NETCore.ILAsm" GeneratePathProperty="true" ExcludeAssets="all" />
   </ItemGroup>
-</Project>
+</Project>

eng/targets/ILDAsm.targets

@@ -11,6 +11,12 @@
       <Visible>false</Visible>
       <Pack>false</Pack>
     </Content>
+    <Content Include="$(Pkgruntime_linux-arm64_Microsoft_NETCore_ILDAsm)\runtimes\**\*.*">
+      <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
+      <LinkBase>runtimes</LinkBase>
+      <Visible>false</Visible>
+      <Pack>false</Pack>
+    </Content>
     <Content Include="$(Pkgruntime_linux-x64_Microsoft_NETCore_ILDAsm)\runtimes\**\*.*">
       <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
       <LinkBase>runtimes</LinkBase>
@@ -25,7 +31,8 @@
     </Content>
 
     <PackageReference Include="runtime.win-x64.Microsoft.NETCore.ILDAsm" GeneratePathProperty="true" ExcludeAssets="all" />
+    <PackageReference Include="runtime.linux-arm64.Microsoft.NETCore.ILDAsm" GeneratePathProperty="true" ExcludeAssets="all" />
     <PackageReference Include="runtime.linux-x64.Microsoft.NETCore.ILDAsm" GeneratePathProperty="true" ExcludeAssets="all" />
     <PackageReference Include="runtime.osx-x64.Microsoft.NETCore.ILDAsm" GeneratePathProperty="true" ExcludeAssets="all" />
   </ItemGroup>
-</Project>
+</Project>

src/Compilers/Test/Core/Metadata/IlasmUtilities.cs

@@ -6,6 +6,7 @@
 
 using System;
 using System.IO;
+using System.Runtime.InteropServices;
 using Roslyn.Test.Utilities;
 using Roslyn.Utilities;
 using Xunit;
@@ -22,6 +23,17 @@ public static DisposableFile CreateTempAssembly(string declarations, bool prepen
             return new DisposableFile(assemblyPath);
         }
 
+        private static string GetArchitecture()
+        {
+#if NET8_0_OR_GREATER
+            return RuntimeInformation.ProcessArchitecture.ToString().ToLowerInvariant();
+#else
+            return "x64";
+#endif
+        }
+
+        public static readonly string Architecture = GetArchitecture();
+
         private static string GetIlasmPath()
         {
             if (ExecutionConditionUtil.IsWindowsDesktop)
@@ -46,7 +58,7 @@ private static string GetIlasmPath()
             }
             else if (ExecutionConditionUtil.IsLinux)
             {
-                ridName = "linux-x64";
+                ridName = $"linux-{GetArchitecture()}";
             }
             else
             {

src/Tools/BuildValidator/BuildValidator.csproj

@@ -19,6 +19,7 @@
     <ProjectReference Include="..\..\Compilers\CSharp\Portable\Microsoft.CodeAnalysis.CSharp.csproj" />
     <ProjectReference Include="..\..\Compilers\VisualBasic\Portable\Microsoft.CodeAnalysis.VisualBasic.vbproj" />
     <ProjectReference Include="..\..\Compilers\Core\Rebuild\Microsoft.CodeAnalysis.Rebuild.csproj" />
+    <ProjectReference Include="..\..\Compilers\Test\Core\Microsoft.CodeAnalysis.Test.Utilities.csproj" />
   </ItemGroup>
 
   <ItemGroup>

src/Tools/BuildValidator/IldasmUtilities.cs

@@ -27,7 +27,8 @@ private static string GetIldasmPath()
             }
             else if (RuntimeInformation.IsOSPlatform(OSPlatform.Linux))
             {
-                ridName = "linux-x64";
+                var architecture = Microsoft.CodeAnalysis.Test.Utilities.IlasmUtilities.Architecture;
+                ridName = $"linux-{architecture}";
             }
             else
             {

src/Tools/Source/RunTests/Options.cs

@@ -141,7 +141,7 @@ public Options(
         internal static Options? Parse(string[] args)
         {
             string? dotnetFilePath = null;
-            var architecture = "x64";
+            var architecture = Microsoft.CodeAnalysis.Test.Utilities.IlasmUtilities.Architecture;
             var includeHtml = false;
             var testRuntime = TestRuntime.Both;
             var configuration = "Debug";

src/Tools/Source/RunTests/RunTests.csproj

@@ -31,4 +31,4 @@
   <Target Name="CopyCustomContent" AfterTargets="AfterBuild" Condition="$([MSBuild]::IsOSPlatform('Windows'))">
     <Copy SourceFiles="@(_CopyItems)" DestinationFolder="$(OutDir)/VSIXExpInstaller" />
   </Target>
-</Project>
+</Project>