Implement safepointing of threads

runtime/vm/native_entry.cc

Index: runtime/vm/native_entry.cc
diff --git a/runtime/vm/native_entry.cc b/runtime/vm/native_entry.cc
index 92a99e8c7d59d24b3270c4f286be79947a2e1c2e..5ae182ccbb3c07fa2a7d4a1c7dfa1eaeec21384d 100644
--- a/runtime/vm/native_entry.cc
+++ b/runtime/vm/native_entry.cc
@@ -12,6 +12,7 @@
 #include "vm/dart_api_state.h"
 #include "vm/object_store.h"
 #include "vm/reusable_handles.h"
+#include "vm/safepoint.h"
 #include "vm/stack_frame.h"
 #include "vm/symbols.h"
 #include "vm/tags.h"
@@ -33,12 +34,16 @@ NativeFunction NativeEntry::ResolveNative(const Library& library,
     // class belongs in.
     return NULL;
   }
-  Dart_EnterScope();  // Enter a new Dart API scope as we invoke API entries.
-  Dart_NativeEntryResolver resolver = library.native_entry_resolver();
-  Dart_NativeFunction native_function =
-      resolver(Api::NewHandle(Thread::Current(), function_name.raw()),
-               number_of_arguments, auto_setup_scope);
-  Dart_ExitScope();  // Exit the Dart API scope.
+  Dart_NativeFunction native_function = NULL;
+  {
+    Thread* T = Thread::Current();
+    TransitionVMToNative transition(T);
+    Dart_EnterScope();  // Enter a new Dart API scope as we invoke API entries.
+    Dart_NativeEntryResolver resolver = library.native_entry_resolver();
+    native_function = resolver(Api::NewHandle(T, function_name.raw()),
+                               number_of_arguments, auto_setup_scope);
+    Dart_ExitScope();  // Exit the Dart API scope.
+  }
   return reinterpret_cast<NativeFunction>(native_function);
 }
 
@@ -101,6 +106,7 @@ void NativeEntry::NativeCallWrapper(Dart_NativeArguments args,
   ApiLocalScope* current_top_scope = thread->api_top_scope();
   ApiLocalScope* scope = thread->api_reusable_scope();
   TRACE_NATIVE_CALL("0x%" Px "", reinterpret_cast<uintptr_t>(func));
+  TransitionGeneratedToNative transition(thread);
   if (scope == NULL) {
     scope = new ApiLocalScope(current_top_scope,
                               thread->top_exit_frame_info());
@@ -173,6 +179,7 @@ void NativeEntry::LinkNativeCall(Dart_NativeArguments args) {
 #endif
 
   {
+    TransitionGeneratedToVM transition(arguments->thread());
     StackZone zone(arguments->thread());
 
     DartFrameIterator iterator;