Support cross CG2 which is not running on helix

Author: am11

src/coreclr/tools/r2rtest/Crossgen2Runner.cs

@@ -24,12 +24,15 @@ class Crossgen2RunnerOptions
     class Crossgen2Runner : CompilerRunner
     {
         private Crossgen2RunnerOptions Crossgen2RunnerOptions;
+        private bool IsAssembly => _options.Crossgen2Path != null && _options.Crossgen2Path.FullName.EndsWith(".dll");
 
         // Crossgen2 runs as a standalone binary
         protected override string CompilerRelativePath => "";
         protected override string CompilerFileName => "";
 
-        protected override string CompilerPath => _options.Crossgen2Path != null ? _options.Crossgen2Path.FullName : Path.Combine(_options.CoreRootDirectory.FullName, "crossgen2", RuntimeInformation.IsOSPlatform(OSPlatform.Windows) ? "crossgen2.exe" : "crossgen2");
+        protected override string CompilerPath => IsAssembly ? _options.DotNetCli : _options.Crossgen2Path?.FullName
+            ?? Path.Combine(_options.CoreRootDirectory.FullName, "crossgen2", RuntimeInformation.IsOSPlatform(OSPlatform.Windows) ? "crossgen2.exe" : "crossgen2");
+
         public override CompilerIndex Index => CompilerIndex.CPAOT;
 
         protected readonly List<string> _referenceFiles = new();
@@ -65,6 +68,8 @@ public Crossgen2Runner(BuildOptions options, Crossgen2RunnerOptions crossgen2Run
         public override ProcessParameters CompilationProcess(string outputFileName, IEnumerable<string> inputAssemblyFileNames)
         {
             ProcessParameters processParameters = base.CompilationProcess(outputFileName, inputAssemblyFileNames);
+            if (IsAssembly)
+                processParameters.Arguments = $"{_options.Crossgen2Path.FullName} {processParameters.Arguments}";
 
             // DOTNET_ variables
             processParameters.EnvironmentOverrides["DOTNET_GCStress"] = "";

src/tests/build.proj

@@ -670,7 +670,7 @@
       <CrossgenCmd Condition="'$(__CompositeBuildMode)' == ''">$(CrossgenCmd) --crossgen2-parallelism 1</CrossgenCmd>
 
       <CrossgenCmd>$(CrossgenCmd) --verify-type-and-field-layout</CrossgenCmd>
-      <CrossgenCmd>$(CrossgenCmd) --crossgen2-path "$(CORE_ROOT)\crossgen2\crossgen2$(ExeSuffix)"</CrossgenCmd>
+      <CrossgenCmd>$(CrossgenCmd) --crossgen2-path "$(__BinDir)\$(BuildArchitecture)\crossgen2\tools\crossgen2.dll"</CrossgenCmd>
     </PropertyGroup>
 
     <Message Importance="High" Text="$(MsgPrefix)Compiling framework using Crossgen2: $(CrossgenCmd)" />