Collect type profile for DevTools.

src/ast/ast.h

Index: src/ast/ast.h
diff --git a/src/ast/ast.h b/src/ast/ast.h
index c3790b34b377fe448289a171d066207cdb8e998e..118a6113269d063b807b2ed1a768cec92ebc59d7 100644
--- a/src/ast/ast.h
+++ b/src/ast/ast.h
@@ -2414,9 +2414,19 @@ class Assignment final : public Expression {
   }
 
   void AssignFeedbackSlots(FeedbackVectorSpec* spec, LanguageMode language_mode,
-                           FeedbackSlotCache* cache);
+                           FeedbackSlotCache* cache,
+                           bool collect_type_profile = false);
   FeedbackSlot AssignmentSlot() const { return slot_; }
 
+  FeedbackSlot CollectTypeProfileSlot() const {

[Yang, 2017/03/09 10:28:27]

CollectTypeProfileSlot sounds like an action. Can we rename this to
TypeProfileSlot?

[Franzi, 2017/03/10 12:14:28]

Done.

+    DCHECK(HasCollectTypeProfileSlot());
+    return collect_type_profile_slot_;
+  }
+
+  bool HasCollectTypeProfileSlot() const {
+    return CollectTypeProfileSlotField::decode(bit_field_);

[Yang, 2017/03/09 10:28:27]

Do we really need this bit in the bit field? Can we just check whether the
FeedbackSlot is invalid?

[Franzi, 2017/03/10 12:14:28]

Done.

+  }
+
  private:
   friend class AstNodeFactory;
 
@@ -2432,12 +2442,16 @@ class Assignment final : public Expression {
   class StoreModeField
       : public BitField<KeyedAccessStoreMode, KeyTypeField::kNext, 3> {};
   class TokenField : public BitField<Token::Value, StoreModeField::kNext, 7> {};
+  class CollectTypeProfileSlotField
+      : public BitField<bool, TokenField::kNext, 1> {};
 
   FeedbackSlot slot_;
   Expression* target_;
   Expression* value_;
   BinaryOperation* binary_operation_;
   SmallMapList receiver_types_;
+
+  FeedbackSlot collect_type_profile_slot_;
 };