[wasm][debugger] Implement support to modify values. (#49557)

* [wasm][debugger] Implement support to modify values.

* Apply suggestions from code review

Co-authored-by: Larry Ewing <lewing@microsoft.com>

* Adding first test.

* Adding more tests, fixing boolean behavior, ignore value change when the new value type is incompatible.

* Implement set value on object -> property and attribute.

* Fix compilation

* Changing what @radical suggested.

* Adding tests.

* Adding test.

* Fix what @radical suggested.

* Fix compilation.

* Fix what @radical suggested.

Co-authored-by: Larry Ewing <lewing@microsoft.com>

Author: thaystg

src/mono/mono/mini/debugger-agent.c

@@ -5735,24 +5735,6 @@ set_var (MonoType *t, MonoDebugVarInfo *var, MonoContext *ctx, MonoDomain *domai
 	}
 }
 
-static void
-set_interp_var (MonoType *t, gpointer addr, guint8 *val_buf)
-{
-	int size;
-
-	if (t->byref) {
-		addr = *(gpointer*)addr;
-		g_assert (addr);
-	}
-
-	if (MONO_TYPE_IS_REFERENCE (t))
-		size = sizeof (gpointer);
-	else
-		size = mono_class_value_size (mono_class_from_mono_type_internal (t), NULL);
-
-	memcpy (addr, val_buf, size);
-}
-
 static void
 clear_event_request (int req_id, int etype)
 {
@@ -9183,7 +9165,9 @@ frame_commands (int command, guint8 *p, guint8 *end, Buffer *buf)
 					addr = (guint8*)mini_get_interp_callbacks ()->frame_get_arg (frame->interp_frame, pos);
 				else
 					addr = (guint8*)mini_get_interp_callbacks ()->frame_get_local (frame->interp_frame, pos);
-				set_interp_var (t, addr, val_buf);
+				err = mono_de_set_interp_var (t, addr, val_buf);
+				if (err != ERR_NONE)
+					return err;
 			} else {
 				set_var (t, var, &frame->ctx, frame->de.domain, val_buf, frame->reg_locations, &tls->restore_state.ctx);
 			}
@@ -9214,7 +9198,9 @@ frame_commands (int command, guint8 *p, guint8 *end, Buffer *buf)
 			guint8 *addr;
 
 			addr = (guint8*)mini_get_interp_callbacks ()->frame_get_this (frame->interp_frame);
-			set_interp_var (m_class_get_this_arg (frame->actual_method->klass), addr, val_buf);
+			err = mono_de_set_interp_var (m_class_get_this_arg (frame->actual_method->klass), addr, val_buf);
+			if (err != ERR_NONE)
+				return err;			
 		} else {
 			var = jit->this_var;
 			if (!var) {

src/mono/mono/mini/debugger-engine.c

@@ -1754,5 +1754,24 @@ get_notify_debugger_of_wait_completion_method (void)
 	return notify_debugger_of_wait_completion_method_cache;
 }
 
+DbgEngineErrorCode
+mono_de_set_interp_var (MonoType *t, gpointer addr, guint8 *val_buf)
+{
+	int size;
+
+	if (t->byref) {
+		addr = *(gpointer*)addr;
+		if (!addr)
+			return ERR_INVALID_OBJECT;
+	}
+
+	if (MONO_TYPE_IS_REFERENCE (t))
+		size = sizeof (gpointer);
+	else
+		size = mono_class_value_size (mono_class_from_mono_type_internal (t), NULL);
+
+	memcpy (addr, val_buf, size);
+	return ERR_NONE;
+}
 
 #endif

src/mono/mono/mini/debugger-engine.h

@@ -510,6 +510,8 @@ DbgEngineErrorCode mono_de_ss_create (MonoInternalThread *thread, StepSize size,
 void mono_de_cancel_ss (SingleStepReq *req);
 void mono_de_cancel_all_ss (void);
 
+DbgEngineErrorCode mono_de_set_interp_var (MonoType *t, gpointer addr, guint8 *val_buf);
+
 gboolean set_set_notification_for_wait_completion_flag (DbgEngineStackFrame *frame);
 MonoClass * get_class_to_get_builder_field(DbgEngineStackFrame *frame);
 gpointer get_this_addr (DbgEngineStackFrame *the_frame);