[TypeFeedbackVector] Root literal arrays in function literals slots

src/ast/ast.h

Index: src/ast/ast.h
diff --git a/src/ast/ast.h b/src/ast/ast.h
index d60cee90a00dacacf4f0c9b152db0b4fa8da1492..7c94d2f9e4aa6afba863bc488e884f1284f79634 100644
--- a/src/ast/ast.h
+++ b/src/ast/ast.h
@@ -2569,6 +2569,20 @@ class FunctionLiteral final : public Expression {
   }
   LanguageMode language_mode() const;
 
+  void AssignFeedbackVectorSlots(Isolate* isolate, FeedbackVectorSpec* spec,
+                                 FeedbackVectorSlotCache* cache) {
+    if (FLAG_strong_rooted_literals) {
+      literal_feedback_slot_ =
+          spec->AddCreateClosureSlot(materialized_literal_count_ + 1);
+    } else {
+      literal_feedback_slot_ = FeedbackVectorSlot::Invalid();
+    }
+  }
+
+  FeedbackVectorSlot LiteralFeedbackSlot() const {
+    return literal_feedback_slot_;
+  }
+
   static bool NeedsHomeObject(Expression* expr);
 
   int materialized_literal_count() { return materialized_literal_count_; }
@@ -2756,6 +2770,7 @@ class FunctionLiteral final : public Expression {
   Handle<String> inferred_name_;
   AstProperties ast_properties_;
   int function_literal_id_;
+  FeedbackVectorSlot literal_feedback_slot_;
 };
 
 // Property is used for passing information
@@ -2855,6 +2870,25 @@ class NativeFunctionLiteral final : public Expression {
  public:
   Handle<String> name() const { return name_->string(); }
   v8::Extension* extension() const { return extension_; }
+  FeedbackVectorSlot LiteralFeedbackSlot() const {
+    return literal_feedback_slot_;
+  }
+
+  void AssignFeedbackVectorSlots(Isolate* isolate, FeedbackVectorSpec* spec,
+                                 FeedbackVectorSlotCache* cache) {
+    // TODO(mvstanton): It's actually silly to create these slots.
+    // At the very least, can we use the FeedbackVectorSlotCache to make
+    // sure we only allocate 1 for a given function and constantly reuse it?
+    if (FLAG_strong_rooted_literals) {
+      // 0 is a magic number here. It means we are holding the literals
+      // array for a native function literal, which needs to be
+      // the empty literals array.
+      // TODO(mvstanton): better way to deal with this?
+      literal_feedback_slot_ = spec->AddCreateClosureSlot(0);
+    } else {
+      literal_feedback_slot_ = FeedbackVectorSlot::Invalid();
+    }
+  }
 
  private:
   friend class AstNodeFactory;
@@ -2867,6 +2901,7 @@ class NativeFunctionLiteral final : public Expression {
 
   const AstRawString* name_;
   v8::Extension* extension_;
+  FeedbackVectorSlot literal_feedback_slot_;
 };