Experimental code to detect transitive closure of parser code which causes new-space allocations

runtime/vm/parser.h

Index: runtime/vm/parser.h
diff --git a/runtime/vm/parser.h b/runtime/vm/parser.h
index c7f766efe829abc6ed46fa580f9fdca96c627e1c..983715fc9e03d4708cc1abba5b6b1b0a2ba76d51 100644
--- a/runtime/vm/parser.h
+++ b/runtime/vm/parser.h
@@ -261,6 +261,23 @@ class ParsedFunction : public ZoneAllocated {
   DISALLOW_COPY_AND_ASSIGN(ParsedFunction);
 };
 
+class EnterParserScope : public StackResource {
+ public:
+  explicit EnterParserScope(Thread* thread);
+  virtual ~EnterParserScope();
+
+ private:
+  bool old_;
+};
+
+class LeaveParserScope : public StackResource {
+ public:
+  explicit LeaveParserScope(Thread* thread);
+  virtual ~LeaveParserScope();
+
+ private:
+  bool old_;
+};
 
 class Parser : public ValueObject {
  public:
@@ -949,6 +966,8 @@ class Parser : public ValueObject {
   Thread* thread_;    // Cached current thread.
   Isolate* isolate_;  // Cached current isolate.
 
+  EnterParserScope enter_parser_scope_;
+
   // It is Heap::kNew for mutator thread and Heap::kOld for other threads (e.g.
   // background compiler).
   Heap::Space allocation_space_;