[browser] Move reflection from JS to C# (#98391)

src/libraries/Common/src/Interop/Browser/Interop.Runtime.cs

@@ -2,6 +2,7 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 
 using System;
+using System.Reflection;
 using System.Runtime.CompilerServices;
 
 internal static partial class Interop
@@ -25,8 +26,6 @@ internal static unsafe partial class Runtime
         public static extern void InvokeJSFunctionSend(nint targetNativeTID, nint functionHandle, nint data);
 #endif
 
-        [MethodImpl(MethodImplOptions.InternalCall)]
-        public static extern unsafe void BindCSFunction(in string fully_qualified_name, int signature_hash, void* signature, out int is_exception, out object result);
         [MethodImpl(MethodImplOptions.InternalCall)]
         public static extern void ResolveOrRejectPromise(nint data);
 #if FEATURE_WASM_MANAGED_THREADS
@@ -65,7 +64,7 @@ internal static unsafe partial class Runtime
         [MethodImpl(MethodImplOptions.InternalCall)]
         public static extern void CancelPromise(nint gcHandle);
 #endif
-
-
+        [MethodImplAttribute(MethodImplOptions.InternalCall)]
+        internal static extern void SetEntryAssembly(Assembly assembly, int entryPointMetadataToken);
     }
 }

src/libraries/System.Runtime.InteropServices.JavaScript/src/Resources/Strings.resx

@@ -138,8 +138,8 @@
   <data name="MissingManagedEntrypointHandle" xml:space="preserve">
     <value>Managed entrypoint handle is not set.</value>
   </data>
-  <data name="CannotResolveManagedEntrypointHandle" xml:space="preserve">
-    <value>Cannot resolve managed entrypoint handle.</value>
+  <data name="CannotResolveManagedEntrypoint" xml:space="preserve">
+    <value>Cannot resolve managed entrypoint {0} in assembly {1}.</value>
   </data>
   <data name="ReturnTypeNotSupportedForMain" xml:space="preserve">
     <value>Return type '{0}' from main method in not supported.</value>

src/libraries/System.Runtime.InteropServices.JavaScript/src/System/Runtime/InteropServices/JavaScript/Interop/JavaScriptExports.cs

@@ -1,14 +1,11 @@
 // Licensed to the .NET Foundation under one or more agreements.
 // The .NET Foundation licenses this file to you under the MIT license.
 
-using System.Collections.Generic;
 using System.Diagnostics.CodeAnalysis;
-using System.IO;
 using System.Reflection;
 using System.Runtime.CompilerServices;
 using System.Threading;
 using System.Threading.Tasks;
-using static System.Runtime.InteropServices.JavaScript.JSHostImplementation;
 
 namespace System.Runtime.InteropServices.JavaScript
 {
@@ -18,87 +15,35 @@ namespace System.Runtime.InteropServices.JavaScript
     internal static unsafe partial class JavaScriptExports
     {
         // the marshaled signature is:
-        // Task<int>? CallEntrypoint(MonoMethod* entrypointPtr, string[] args)
+        // Task<int>? CallEntrypoint(string mainAssemblyName, string[] args, bool waitForDebugger)
         public static void CallEntrypoint(JSMarshalerArgument* arguments_buffer)
         {
             ref JSMarshalerArgument arg_exc = ref arguments_buffer[0]; // initialized by caller in alloc_stack_frame()
             ref JSMarshalerArgument arg_result = ref arguments_buffer[1]; // initialized by caller in alloc_stack_frame()
             ref JSMarshalerArgument arg_1 = ref arguments_buffer[2]; // initialized and set by caller
             ref JSMarshalerArgument arg_2 = ref arguments_buffer[3]; // initialized and set by caller
+            ref JSMarshalerArgument arg_3 = ref arguments_buffer[4]; // initialized and set by caller
             try
             {
 #if FEATURE_WASM_MANAGED_THREADS
                 // when we arrive here, we are on the thread which owns the proxies
                 arg_exc.AssertCurrentThreadContext();
 #endif
 
-                arg_1.ToManaged(out IntPtr entrypointPtr);
-                if (entrypointPtr == IntPtr.Zero)
-                {
-                    throw new MissingMethodException(SR.MissingManagedEntrypointHandle);
-                }
+                arg_1.ToManaged(out string? mainAssemblyName);
+                arg_2.ToManaged(out string?[]? args);
+                arg_3.ToManaged(out bool waitForDebugger);
 
-                RuntimeMethodHandle methodHandle = GetMethodHandleFromIntPtr(entrypointPtr);
-                // this would not work for generic types. But Main() could not be generic, so we are fine.
-                MethodInfo? method = MethodBase.GetMethodFromHandle(methodHandle) as MethodInfo;
-                if (method == null)
-                {
-                    throw new InvalidOperationException(SR.CannotResolveManagedEntrypointHandle);
-                }
+                Task<int>? result = JSHostImplementation.CallEntrypoint(mainAssemblyName, args, waitForDebugger);
 
-                arg_2.ToManaged(out string?[]? args);
-                object[] argsToPass = System.Array.Empty<object>();
-                Task<int>? result = null;
-                var parameterInfos = method.GetParameters();
-                if (parameterInfos.Length > 0 && parameterInfos[0].ParameterType == typeof(string[]))
-                {
-                    argsToPass = new object[] { args ?? System.Array.Empty<string>() };
-                }
-                if (method.ReturnType == typeof(void))
-                {
-                    method.Invoke(null, argsToPass);
-                }
-                else if (method.ReturnType == typeof(int))
-                {
-                    int intResult = (int)method.Invoke(null, argsToPass)!;
-                    result = Task.FromResult(intResult);
-                }
-                else if (method.ReturnType == typeof(Task))
-                {
-                    Task methodResult = (Task)method.Invoke(null, argsToPass)!;
-                    TaskCompletionSource<int> tcs = new TaskCompletionSource<int>();
-                    result = tcs.Task;
-                    methodResult.ContinueWith((t) =>
-                    {
-                        if (t.IsFaulted)
-                        {
-                            tcs.SetException(t.Exception!);
-                        }
-                        else
-                        {
-                            tcs.SetResult(0);
-                        }
-                    }, TaskScheduler.Default);
-                }
-                else if (method.ReturnType == typeof(Task<int>))
-                {
-                    result = (Task<int>)method.Invoke(null, argsToPass)!;
-                }
-                else
-                {
-                    throw new InvalidOperationException(SR.Format(SR.ReturnTypeNotSupportedForMain, method.ReturnType.FullName));
-                }
                 arg_result.ToJS(result, (ref JSMarshalerArgument arg, int value) =>
                 {
                     arg.ToJS(value);
                 });
             }
             catch (Exception ex)
             {
-                if (ex is TargetInvocationException refEx && refEx.InnerException != null)
-                    ex = refEx.InnerException;
-
-                arg_exc.ToJS(ex);
+                Environment.FailFast("CallEntrypoint: Unexpected synchronous failure. " + ex);
             }
         }
 
@@ -163,7 +108,7 @@ public static void ReleaseJSOwnedObjectByGCHandle(JSMarshalerArgument* arguments
             }
             catch (Exception ex)
             {
-                arg_exc.ToJS(ex);
+                Environment.FailFast("ReleaseJSOwnedObjectByGCHandle: Unexpected synchronous failure. " + ex);
             }
         }
 
@@ -188,7 +133,7 @@ public static void CallDelegate(JSMarshalerArgument* arguments_buffer)
 #endif
 
                 GCHandle callback_gc_handle = (GCHandle)arg_1.slot.GCHandle;
-                if (callback_gc_handle.Target is ToManagedCallback callback)
+                if (callback_gc_handle.Target is JSHostImplementation.ToManagedCallback callback)
                 {
                     // arg_2, arg_3, arg_4, arg_res are processed by the callback
                     callback(arguments_buffer);
@@ -219,7 +164,7 @@ public static void CompleteTask(JSMarshalerArgument* arguments_buffer)
                 // when we arrive here, we are on the thread which owns the proxies
                 var ctx = arg_exc.AssertCurrentThreadContext();
                 var holder = ctx.GetPromiseHolder(arg_1.slot.GCHandle);
-                ToManagedCallback callback;
+                JSHostImplementation.ToManagedCallback callback;
 
 #if FEATURE_WASM_MANAGED_THREADS
                 lock (ctx)
@@ -260,7 +205,7 @@ public static void CompleteTask(JSMarshalerArgument* arguments_buffer)
             }
             catch (Exception ex)
             {
-                arg_exc.ToJS(ex);
+                Environment.FailFast("CompleteTask: Unexpected synchronous failure. " + ex);
             }
         }
 
@@ -318,6 +263,30 @@ public static void InstallMainSynchronizationContext(JSMarshalerArgument* argume
 
 #endif
 
+        // the marshaled signature is:
+        // Task BindAssemblyExports(string assemblyName)
+        public static void BindAssemblyExports(JSMarshalerArgument* arguments_buffer)
+        {
+            ref JSMarshalerArgument arg_exc = ref arguments_buffer[0]; // initialized by caller in alloc_stack_frame()
+            ref JSMarshalerArgument arg_result = ref arguments_buffer[1]; // used as return value
+            ref JSMarshalerArgument arg_1 = ref arguments_buffer[2];// initialized and set by caller
+            try
+            {
+                string? assemblyName;
+                // when we arrive here, we are on the thread which owns the proxies
+                arg_exc.AssertCurrentThreadContext();
+                arg_1.ToManaged(out assemblyName);
+
+                var result = JSHostImplementation.BindAssemblyExports(assemblyName);
+
+                arg_result.ToJS(result);
+            }
+            catch (Exception ex)
+            {
+                Environment.FailFast("BindAssemblyExports: Unexpected synchronous failure. " + ex);
+            }
+        }
+
         [MethodImpl(MethodImplOptions.NoInlining)] // profiler needs to find it executed under this name
         public static void StopProfile()
         {

src/libraries/System.Runtime.InteropServices.JavaScript/src/System/Runtime/InteropServices/JavaScript/Interop/JavaScriptImports.Generated.cs

@@ -45,6 +45,10 @@ internal static unsafe partial class JavaScriptImports
         [JSImport("INTERNAL.dynamic_import")]
         // TODO: the continuation should be running on deputy or TP in MT
         public static partial Task<JSObject> DynamicImport(string moduleName, string moduleUrl);
+
+        [JSImport("INTERNAL.mono_wasm_bind_cs_function")]
+        public static partial void BindCSFunction(IntPtr monoMethod, string assemblyName, string namespaceName, string shortClassName, string methodName, int signatureHash, IntPtr signature);
+
 #if FEATURE_WASM_MANAGED_THREADS
         [JSImport("INTERNAL.thread_available")]
         // TODO: the continuation should be running on deputy or TP in MT

src/libraries/System.Runtime.InteropServices.JavaScript/src/System/Runtime/InteropServices/JavaScript/JSFunctionBinding.cs

@@ -191,10 +191,11 @@ public static JSFunctionBinding BindManagedFunction(string fullyQualifiedName, i
         {
             if (RuntimeInformation.OSArchitecture != Architecture.Wasm)
                 throw new PlatformNotSupportedException();
-#if FEATURE_WASM_MANAGED_THREADS
-            JSProxyContext.AssertIsInteropThread();
-#endif
-            return BindManagedFunctionImpl(fullyQualifiedName, signatureHash, signatures);
+
+            // this could be called by assembly module initializer from Net7 code-gen
+            // on wrong thread, in which case we will bind it to UI thread
+
+            return JSHostImplementation.BindManagedFunction(fullyQualifiedName, signatureHash, signatures);
         }
 
 #if !DEBUG
@@ -407,21 +408,6 @@ internal static unsafe JSFunctionBinding BindJSImportImpl(string functionName, s
             return signature;
         }
 
-        internal static unsafe JSFunctionBinding BindManagedFunctionImpl(string fullyQualifiedName, int signatureHash, ReadOnlySpan<JSMarshalerType> signatures)
-        {
-            var signature = JSHostImplementation.GetMethodSignature(signatures, null, null);
-
-            Interop.Runtime.BindCSFunction(fullyQualifiedName, signatureHash, signature.Header, out int isException, out object exceptionMessage);
-            if (isException != 0)
-            {
-                throw new JSException((string)exceptionMessage);
-            }
-
-            JSHostImplementation.FreeMethodSignatureBuffer(signature);
-
-            return signature;
-        }
-
 #if !DEBUG
         [MethodImpl(MethodImplOptions.AggressiveInlining)]
 #endif