[wasm] optimize out 'is this method MulticastDelegate.Invoke' checks in aot->interp transitions (#80181)

* When creating an InterpMethod, identify whether it is MulticastDelegate.Invoke and store that in a flag to optimize interp_entry
* Always inline some jiterpreter APIs

Author: kg

src/mono/mono/mini/interp/interp-internals.h

@@ -169,6 +169,8 @@ struct InterpMethod {
 	unsigned int vararg : 1;
 	unsigned int optimized : 1;
 	unsigned int needs_thread_attach : 1;
+	// If set, this method is MulticastDelegate.Invoke
+	unsigned int is_invoke : 1;
 #if PROFILE_INTERP
 	long calls;
 	long opcounts;
@@ -298,9 +300,6 @@ mono_interp_jit_call_supported (MonoMethod *method, MonoMethodSignature *sig);
 void
 mono_interp_error_cleanup (MonoError *error);
 
-gboolean
-mono_interp_is_method_multicastdelegate_invoke (MonoMethod *method);
-
 #if HOST_BROWSER
 
 gboolean

src/mono/mono/mini/interp/interp.c

@@ -488,6 +488,8 @@ mono_interp_get_imethod (MonoMethod *method)
 	imethod->hasthis = sig->hasthis;
 	imethod->vararg = sig->call_convention == MONO_CALL_VARARG;
 	imethod->code_type = IMETHOD_CODE_UNKNOWN;
+	// This flag allows us to optimize out the interp_entry 'is this a delegate invoke' checks
+	imethod->is_invoke = (m_class_get_parent (method->klass) == mono_defaults.multicastdelegate_class) && !strcmp(method->name, "Invoke");
 	// always optimize code if tiering is disabled
 	// always optimize wrappers
 	if (!mono_interp_tiering_enabled () || method->wrapper_type != MONO_WRAPPER_NONE)
@@ -2161,12 +2163,6 @@ typedef struct {
 	gpointer *many_args;
 } InterpEntryData;
 
-static MONO_ALWAYS_INLINE gboolean
-is_method_multicastdelegate_invoke (MonoMethod *method)
-{
-	return m_class_get_parent (method->klass) == mono_defaults.multicastdelegate_class && !strcmp (method->name, "Invoke");
-}
-
 /* Main function for entering the interpreter from compiled code */
 // Do not inline in case order of frame addresses matters.
 static MONO_NEVER_INLINE void
@@ -2196,7 +2192,7 @@ interp_entry (InterpEntryData *data)
 
 	method = rmethod->method;
 
-	if (is_method_multicastdelegate_invoke(method)) {
+	if (rmethod->is_invoke) {
 		/*
 		 * This happens when AOT code for the invoke wrapper is not found.
 		 * Have to replace the method with the wrapper here, since the wrapper depends on the delegate.
@@ -8591,36 +8587,30 @@ mono_jiterp_ld_delegate_method_ptr (gpointer *destination, MonoDelegate **source
 	*destination = imethod_to_ftnptr (del->interp_method, FALSE);
 }
 
-void
+MONO_ALWAYS_INLINE void
 mono_jiterp_check_pending_unwind (ThreadContext *context)
 {
 	return check_pending_unwind (context);
 }
 
-void *
+MONO_ALWAYS_INLINE void *
 mono_jiterp_get_context (void)
 {
 	return get_context ();
 }
 
-gpointer
+MONO_ALWAYS_INLINE gpointer
 mono_jiterp_frame_data_allocator_alloc (FrameDataAllocator *stack, InterpFrame *frame, int size)
 {
 	return frame_data_allocator_alloc(stack, frame, size);
 }
 
-gboolean
+MONO_ALWAYS_INLINE gboolean
 mono_jiterp_isinst (MonoObject* object, MonoClass* klass)
 {
 	return mono_interp_isinst (object, klass);
 }
 
-gboolean
-mono_interp_is_method_multicastdelegate_invoke (MonoMethod *method)
-{
-	return is_method_multicastdelegate_invoke (method);
-}
-
 // after interp_entry_prologue the wrapper will set up all the argument values
 //  in the correct place and compute the stack offset, then it passes that in to this
 //  function in order to actually enter the interpreter and process the return value

src/mono/mono/mini/interp/jiterpreter.c

@@ -563,7 +563,6 @@ EMSCRIPTEN_KEEPALIVE stackval *
 mono_jiterp_interp_entry_prologue (JiterpEntryData *data, void *this_arg)
 {
 	stackval *sp_args;
-	MonoMethod *method;
 	InterpMethod *rmethod;
 	ThreadContext *context;
 
@@ -572,23 +571,21 @@ mono_jiterp_interp_entry_prologue (JiterpEntryData *data, void *this_arg)
 	jiterp_assert(data);
 	rmethod = data->header.rmethod;
 	jiterp_assert(rmethod);
-	method = rmethod->method;
-	jiterp_assert(method);
 
-	if (mono_interp_is_method_multicastdelegate_invoke(method)) {
+	// Is this method MulticastDelegate.Invoke?
+	if (rmethod->is_invoke) {
 		// Copy the current state of the cache before using it
 		JiterpEntryDataCache cache = data->cache;
 		if (this_arg && (cache.delegate_invoke_is_for == (MonoDelegate*)this_arg)) {
 			// We previously cached the invoke for this delegate
-			method = cache.delegate_invoke;
 			data->header.rmethod = rmethod = cache.delegate_invoke_rmethod;
 		} else {
 			/*
 			* This happens when AOT code for the invoke wrapper is not found.
 			* Have to replace the method with the wrapper here, since the wrapper depends on the delegate.
 			*/
 			MonoDelegate *del = (MonoDelegate*)this_arg;
-			method = mono_marshal_get_delegate_invoke (method, del);
+			MonoMethod *method = mono_marshal_get_delegate_invoke (rmethod->method, del);
 			data->header.rmethod = rmethod = mono_interp_get_imethod (method);
 
 			// Cache the delegate invoke. This works because data was allocated statically

src/mono/mono/mini/interp/tiering.c

@@ -32,6 +32,7 @@ get_tier_up_imethod (InterpMethod *imethod)
 	new_imethod->code_type = imethod->code_type;
 	new_imethod->rtype = imethod->rtype;
 	new_imethod->param_types = imethod->param_types;
+	new_imethod->is_invoke = imethod->is_invoke;
 	new_imethod->optimized = TRUE;
 	new_imethod->prof_flags = imethod->prof_flags;
 

src/mono/wasm/runtime/jiterpreter-interp-entry.ts

@@ -30,6 +30,13 @@ typedef struct {
 	gpointer args [16];
 	gpointer *many_args;
 } InterpEntryData;
+
+typedef struct {
+	InterpMethod *rmethod; // 0
+	ThreadContext *context; // 4
+	gpointer orig_domain; // 8
+	gpointer attach_cookie; // 12
+} JiterpEntryDataHeader;
 */
 
 const // offsetOfStack = 12,